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Jeff Masters on California Drought

Sunday, February 2nd, 2014

California’s Sierra Snowpack Only 12% of Average, a Record Low

By Dr. Jeff Masters
Published: 4:32 PM GMT on January 31, 2014

California’s first significant snow storm of 2014 hit the Sierras on Wednesday and Thursday, dumping up to 2 feet of snow, with a melted water equivalent of up to two inches. However, this modest snowstorm was not enough to keep the Sierra snowpack from recording its lowest snow amounts in more than 50 years of record keeping during Thursday’s Sierra Snow Survey. The survey found a snow pack that was only 12% of normal for this time of year. Until Thursday, the lowest statewide snowpack measurement at this time of year was 21% of average, in 1991 and 1963, according to the Los Angeles Times. Since snowpack in the Sierras forms a crucial source of water for California, the dismal snow survey results are a huge concern.

Figure 1. Frank Gehrke, chief of the California Cooperative Snow Survey Program for the Department of Water Resources, walks leaves a snow covered meadow after the second snow survey of the year near Echo Summit, Calif., Thursday, Jan. 30, 2014. Despite the overnight snow storm the survey showed the snow depth at 12.4 inches with a water content of only 1.4 inches for this location at this time of the year. Gehrke said that while the recent snow fall will help, it is not enough to impact the water supply.(AP Photo)

The forecast: little drought relief in sight
One of the most persistent and intense ridges of high pressure ever recorded in North America has been anchored over the West Coast since December 2012. While the ridge has occasionally broken down and allowed low pressure systems to leak though, these storms have mostly brought spotty and meager precipitation to California, resulting in California’s driest year on record during 2013. January 2014 could well be its driest January on record. The ridge inevitably builds back after each storm, clamping down on any moisture reaching the state. Since rain-bearing low pressure systems tend to travel along the axis of the jet stream, these storms are being carried along the axis of the ridge, well to the north of California and into Southeast Alaska, leaving California exceptionally dry. The latest runs of the GFS and European models show that the ridge is now building back, and it appears likely that California will see no significant precipitation until at least February 7. A weak upper level low will move along the coast on Sunday and spread some light rain along the immediate coast, but this precipitation will generally be less than 0.25″–too little to have any significant impact on the drought. The ridge will not be as intense when it builds back, though, which gives me some hope that a low pressure system will be able to break the ridge by mid-February and bring the most significant rains of the winter rainy season to California.

Figure 2. One of the key water supply reservoirs for Central California, Lake Oroville, as seen on January 20, 2014. Image credit: California Department of Water Resources.

Worst California drought in 500 years?
UC Berkeley paleoclimatologist B. Lynn Ingram, author of “The West Without Water: What Past Floods, Droughts, and Other Climatic Clues Tell Us About Tomorrow”, said in an interview, “this could potentially be the driest water year in 500 years.” Her research on tree rings shows that California has not experienced such an extreme drought since 1580. “If you go back thousands of years, you see that droughts can go on for years if not decades, and there were some dry periods that lasted over a century, like during the Medieval period and the middle Holocene. The 20th century was unusually mild here, in the sense that the droughts weren’t as severe as in the past. It was a wetter century, and a lot of our development has been based on that.” It’s no wonder, then, that the overall agricultural impact of the drought could reach $1 billion this year, according to the Fresno-based Westlands Water District.

California’s drought woes are part of an on-going 14-year Western U.S. drought that began in 2000, and peaked between 2000 – 2004. A 2012 study titled, Reduction in carbon uptake during turn of the century drought in western North America, found that the 2000 – 2004 drought was the most severe Western North America event of its kind since the last mega drought over 800 years ago, during the years 1146 – 1151. The paper analyzed the latest generation of climate models used for the 2013 IPCC report, which project that the weather conditions that spawned the 2000 – 2004 drought will be the new normal in the Western U.S. by 2030, and will be considered extremely wet by the year 2100. If these dire predictions of a coming “megadrought” are anywhere close to correct, it will be extremely challenging for the Southwest U.S. to support a growing population in the coming decades.

Megadroughts in the Western U.S. can develop from natural causes, as well, and the current pattern of cooler than average ocean temperatures in the Eastern Pacific and warmer than average ocean temperatures in the Atlantic increase the odds of drought conditions like the ones we have seen during the current megadrought. Edward Cook, director of the Tree Ring Laboratory at Columbia University’s Lamont-Doherty Earth Observatory in Palisades, N.Y., said at a presentation last month at the American Geophysical Union meeting that tree ring data show that the area of the West that was affected by severe drought in the Medieval period was much higher and much longer than the current drought. It is “indeed pretty scary,” Cook said. “One lasted 29 years. One lasted 28 years. They span the entire continental United States.” Two megadroughts in the Sierra Nevada of California lasted between 100 and 200 years. Bobby Magill at Climate Center has more on Dr. Cook’s presentation in a post, Is the West’s Dry Spell Really a Megadrought?

Figure 3. Normalized precipitation over Western North America (five-year mean) from 22 climate models used to formulate the 2013 IPCC report, as summarized by Schwalm et al., 2012, Reduction in carbon uptake during turn of the century drought in western North America. The horizontal line marks the precipitation level of the 2000 – 2004 drought, the worst of the past 800 years. Droughts of this intensity are predicted to be the new normal by 2030, and will be considered an outlier of extreme wetness by 2100. The paper states: “This impending drydown of western North America is consistent with present trends in snowpack decline as well as expected in-creases in aridity and extreme climate events,including drought, and is driven by anthropogenically forced increases in temperature with coincident increases in evapotranspiration and decreases in soil moisture. Although regional precipitation patterns are difficult to forecast, climate models tend to underestimate the extent and severity of drought relative to available observations. As such, actual reductions in precipitation may be greater than shown. Forecasted precipitation patterns are consistent with a probable twenty-first century megadrought.” Image credit: Schwalm et al., 2012, Reduction in carbon uptake during turn of the century drought in western North America, Nature Geoscience 5, 551-555, Published online 29 JULY 2012, DOI: 10.1038/NGEO1529,

Related posts
Unprecedented Cut in Colorado River Flow Ordered, Due to Drought, my August 2013 post.

Lessons from 2012: Droughts, not Hurricanes, are the Greater Danger, my November 2012 post.

How Two Reservoirs Have Become Billboards For What Climate Change Is Doing To The American West, August 12, 2013 post by Tom Kenworthy.

Scientists Predicted A Decade Ago Arctic Ice Loss Would Worsen Western Droughts. Is That Happening Already?, June 2013 post by Joe Romm at

Twenty Cities At Risk of Water Shortages, August 14, 2013 wunderground news post by Nick Wiltgen

‪If There’s Global Warming…Why Is It So Cold?‬
It’s been top-ten coldest January on record in the Upper Midwest, and much colder than average over much of the Eastern U.S. However, the that isn’t the case over other portions of the globe, including the Western U.S. and Alaska. Wunderground’s weather historian Christopher C. Burt analyzes the situation in his latest post, How Cold has this January been in the U.S.? He concludes, “this January’s average temperature nationally has probably been close to normal since the western half of the nation has been almost as much above average as the eastern half was below average. The only region that will most likely have experienced a TOP 10 coldest January will be the Upper Midwest.” In the U.S., only four stations set all-time low minimum temperature records in January, compared to 34 that set all-time high maximum temperature records. I’ve been monitoring global temperatures this month, and it appears likely that January will rank between the 5th and 15th warmest January since record keeping began in 1880. Of particular note were the amazingly warm January temperatures in the Balkans. According to weather record researcher Maximiliano Herrera, “over 90% of all stations in the Balkans from Slovenia to Croatia to Bosnia to Serbia To Montenegro to Kosovo etc., have DESTROYED their previous record of warmest January ever (many locations have 100 – 200 years of data.) In many cases the monthly temperatures were 7 – 9°C (13 – 16°F) above average, and the new records were 3 – 4°C above the previous record. This is for THOUSANDS of stations, almost all of them. In Slovenia, for example, Mount Kredarica is the only station in the whole country not to have set its warmest January on record.”

Video 1. ‪If There’s Global Warming … Why Is It So Cold?‬ The latest video from climate videographer Peter Sinclair on the Yale Climate Forum website demonstrates that while it was a very cold January in the Midwest, this has been counterbalanced by record warmth over the Western U.S. and Alaska, caused by an unusually extreme kink in the jet stream.

Another Unexpected Disaster That Was Well Forecast. Based in Atlanta, TWC’s Bryan Norcross concludes that “WARM GROUND + VERY COLD AIR + SNOW + WORKDAY = CHAOS. If the decision-makers understood the formula above, this information should have been sufficient to trigger a proper response.”

Jon Stewart Lays Into Georgia’s Snowpocalypse


2013 Heat Records

Monday, January 20th, 2014
Nine Nations or Territories Set All-Time Heat Records in 2013
By: Dr. Jeff Masters, 2:43 PM GMT on January 20, 2014 +23

It was another notable year for all-time heat records in 2013, with six nations and three territories tying or setting records for hottest temperature on record. No nations set an all-time cold record in 2013. For comparison, five countries and two territories set all-time hottest temperature records in 2012, and the most all-time national heat records in a year was twenty nations and one territory in 2010. Since 2010, 45 nations or territories have set or tied all-time heat records, but only one nation has set an all-time cold temperature record. Since each of those years ranked as one of the top eleven warmest years in Earth’s history, and 2010 was the warmest year on record, this sort of disparity in national heat and cold records is to be expected. Most nations do not maintain official databases of extreme temperature records, the national temperature records I report here are in many cases not official. I use as my source for international weather records Maximiliano Herrera, one of the world’s top climatologists, who maintains a comprehensive list of extreme temperature records for every nation in the world on his website. If you reproduce this list of extremes, please cite Maximiliano Herrera as the primary source of the weather records. Wunderground’s weather historian Christopher C. Burt maintains a database of these national heat and cold records, for 235 nations and territories, on’s extremes page.

Figure 1. A moose takes a dip to cool off in a backyard pool in this photo taken in Big Lake, Alaska on June 17, 2013, by Lonea Moore McGowen (Courtesy KTUU-TV.) Bentalit Lodge, Alaska hit 36.7°C (98°F) on June 17, tying the mark set in Richardson on 15 June 1969 for hottest undisputed temperature in Alaska history. The official heat record for Alaska remains the 100°F registered at Fort Yukon on June 27, 1915. However, there are questions concerning this figure as outlined by our weather historian, Christopher C. Burt.

New all-time national heat records set in 2013

Heard and McDonald Islands (uninhabited territory of Australia) set a new all-time heat record of 26.1°C (79°F) at Split Bay on 1 March. Previous record: 21.6°C set at the same station in April 1992.

Ghana tied its all time highest temperature record with 43.0°C (109.4°F) at Navrongo on 6 March; the same value had also been recorded on 25 February 2010 and 19 April 2010 at the same location.

The United States tied its highest undisputed temperature at the Furnace Creek Visitors Center, Death Valley California, with 53.9°C (129°F) on 30 June. The only higher temperatures ever recorded on the planet occurred in Death Valley on July 10, 12, and 13, 1913, when readings of 134°F, 130°F, and 131°F were recorded. These 100-year-old official hottest temperatures in Earth’s history have many doubters, though, including Mr. Burt, who noted in a 2010 blog post that “The record has been scrutinized perhaps more than any other in the United States. I don’t have much more to add to the debate aside from my belief it is most likely not a valid reading when one looks at all the evidence.

St. Pierre et Miquelon, a French territory off the coast of Newfoundland, Canada, set its all time highest temperature record with 28.3°C (82.9°F) at the St. Pierre Airport on 6 July. Previous record: 28.0°C at St. Pierre town in August 1876 and August 1935.

Greenland, a territory of Denmark, set a new all time highest temperature with 25.9°C (78.6°F) at Maniitsoq Airport on 30 July. Previous record: 25.5°C at Kangerlussuaq on 27 July 1990. There is a claimed 30.1°C measurement at Ivigtut on 23 June 1915, but this is almost certainly a mistake, since the reading doesn’t fit at all with the hourly data of that day, and the station in over a century has never recorded any temperature above 24°C.

Austria set a new national record of highest temperature with 39.9°C (103.8°F) at Dellach im Drautal on 3 August, which beat the old record of 39.7°C set at the same location on 27 July 1983. The 3 August 2013 record was beaten again on 8 August 2013, with a 40.5°C (104.9°F) reading recorded at Bad Deutsch-Altenburg.

Slovenia also set a new all time heat record on 8 August, with 40.8°C at Cerklje Ob krki. Previous record: 40.6°C set at Crnomelj on 5 July 1950.

Japan set a new all-time heat record with 41.0°C (105.8°F) at Shimanto on 12 August. Previous record: 40.9°C at Tajimi and at Kumagaya on 16 August 2007.

Comoros tied its national record of highest temperature at the Hahaya Int. Airport with 35.6°C (96.1°F) on 19 November; the same value was recorded at the former Moroni Airport (its location looks to have been very close of the current international airport) on 31 December 1960.

Figure 2. The official Furnace Creek, Death Valley maximum recording thermometer for the maximum temperature measured on June 30th, 2013. The 129.2°F (54.0°C) reading was the highest June temperature ever measured on Earth. Photo courtesy of Death Valley National Park and NWS-Las Vegas. Note, though, since only whole Fahrenheit figures are official in the U.S., the value was registered as 129°F.

Notable global heat and cold records set in 2013
Hottest temperature in the world in 2013: 53.9°C (129°F) at Death Valley, California, June 30
Coldest temperature in the world in 2013: -81.7°C (-115°F) at Dome A, Antarctica, July 31
Hottest temperature in the Southern Hemisphere: 49.6°C (121.3°F) at Moomba Aero, Australia, January 12
Coldest temperature in the Northern Hemisphere: -64.2°C (-83.6°F) at Summit GEO, Greenland, March 4

Number of major world stations which set their all time highest temperature in 2013: 389
Number of major world stations which set their all time lowest temperature in 2013: 12

On 27 February, 2013, a new February all-time heat record for the Northern Hemisphere was set with 44.5°C (112.1°F) at Abu Na’ Ama (Sudan). Previous record: 44.4°C with two former record holders: Kayes in Mali, and Kiffa in Mauritania.

A day for the history books: European heat wave of 8 August 2013
An incredible heat wave over Central Europe on 8 August 2013 was a day for the history books of world climatology, with two nations and three world capitals setting all-time heat records on the same day. Dozens of stations in six European countries also set all-time heat records that day. The three capitals that set new all-time heat records on 8 August:

Vienna, Austria reached 39.5°C (103.1°F), beating the previous city record of 38.9°C which was recorded in July 1957.

Bratislava, Slovakia reached 39.4°C (102.9°F), beating the previous city record of 38.9°C set in July 2007.

Ljubljana, Slovenia reached as high as 40.2°C (104.4°F), beating for the FIFTH TIME IN SIX DAYS the old record of 38.0°C set in June 1935. This is particularly amazing, since the city has about 150 years of data. This is the sequence:

3 August 38.3°C
4 August 38.4°C
6 August 38.6°C
7 August 39.5°C
8 August 40.2°C

One other world capital set an all-time heat record in 2013: Bangkok, Thailand, which reached 40.1°C (104.2°F) in the Metropolis Station on 26 March, beating the previous record of 40.0°C set in April 1979 and April 2012.

A big thanks goes to Maximiliano Herrera for providing the information in this post.


Winter Forecast fr/The Weather Space

Thursday, October 24th, 2013

2013 – 2014 Winter Forecast Released From


NOTE: The ONLY Way Above Normal is CALIFORNIA for Precipitation … It is not the orange color in the Eastern USA … Orange is Below normal precip!

NOTE: This is the AVERAGE of all three months, Dec/Jan/Feb …

Dec – nationwide warm
Jan – Warm west, cold east
Feb – nationwide warm

Discussion:  Storm pattern for this does not begin till December so anything before this does not count.  During the main winter season of December, January, and February we will see most of he USA under above average temperatures.  With an active southern jet stream and split flow pattern over the Pacific Northwest, this looks to bring the storm track across the Southern USA, impacting California with above average precipitation.  Although this is not an El Nino year, this forecast is made by other means not disclosed.

The active southern branch of the jet will bring above average temperatures to most of the country, with the exception of the extreme Northeastern part from New England through Maine where temperatures will be below normal with an active snow track.

Areas across Texas and into Florida will be in this southern branch jet stream, which means that a number of strong surface lows will develop and bring above average precipitation to both states.  In fact, this pattern brings severe thunderstorms and tornadoes to Florida, and possibly another March 1993 type event.

Furthermore the storm track will go from Florida up through the New England / Northeastern USA.  Despite being above average in temperatures for the season, cold shots will always be likely and one or two storms may become strong nor’easters as this pattern favors such …

The pattern brings surface lows through KS/MO/IA for Blizzard Conditions across Nebraska, South Dakota, North Dakota, and Minnesota.  This will become the norm if lows branch off at the surface from the southern branch jet stream.

The pattern also favors normal temperatures for the Pacific Northwest, with normal rainfall … some areas will see below normal rainfall in those spots though.  This season does not favor an active storm season for the Pacific Northwest.


Dr. Masters on August 2013 Extremes

Tuesday, September 24th, 2013

August 2013 was the globe’s 4th warmest August since records began in 1880, according to NOAA’s National Climatic Data Center (NCDC). NASA rated it the 5th warmest August on record. The year-to-date period of January – August has been the 6th warmest such period on record. August 2013 global land temperatures were the 11th warmest on record, and global ocean temperatures were the 5th warmest on record. August 2013 was the 342nd consecutive month with global temperatures warmer than the 20th century average. Global satellite-measured temperatures in August 2013 for the lowest 8 km of the atmosphere were 14th or 11th warmest in the 35-year record, according to Remote Sensing Systems and the University of Alabama Huntsville (UAH), respectively. Wunderground’s weather historian, Christopher C. Burt, has a comprehensive post on the notable weather events of August 2013 in his August 2013 Global Weather Extremes Summary. The big stories that he highlights are the intense heat waves that hit Central Europe and East Asia, which brought all-time national heat records to Austria, Slovenia, and Japan. Ljubljana, the capital of Slovenia, passed its all-time heat record a remarkable five times during the month.

Figure 1. Departure of temperature from average for August 2013, the 4th warmest August for the globe since record keeping began in 1880. Most of the world’s land areas experienced warmer-than-average monthly temperatures, including Australia, northern South America, western North America, Europe, and much of eastern Asia. Far eastern China, part of eastern Russia north of Japan, and part of northeastern South America were record warm for the month. The southeastern United States, Far East Russia, part of South Africa, Paraguay, and Bolivia were cooler than average. No regions of the globe were record cold. Image credit: National Climatic Data Center (NCDC) .

The six billion-dollar weather disasters of August 2013

Disaster 1. The most damaging billion-dollar weather disaster of August was in Northeast China, where the Nei River overflowed, killing 54 and leaving 97 missing in Fushuan. The flooding killed 118 people and cost $5 billion. In this photo, workers use an excavator to clean up mud after heavy rain hit on August 19, 2013 in Fushuan, in the Liaoning Province of China. Photo by ChinaFotoPress/Getty Images.

Disaster 2. Super Typhoon Utor killed 70 people in China and did $2.6 billion in damage. Utor also did $33 million in damage in the Philippines. This video taken by storm chaser James Reynolds shows debris flying as Typhoon Utor hits Zhapo, China on 14th August 2013.

Disaster 3. Torrential rains, due, in part, to moisture from Typhoon Trami, fell in the Philippines August 18 – 21, causing massive flooding on Luzon Island that cost $2.2 billion. Twenty-seven people were killed, and 60% of metro Manila was under water at the peak of the flood. According to EM-DAT, the International Disaster Database, this was the most expensive natural disaster in Philippine history. In this photo, pedicabs and makeshift rafts ferry office workers and pedestrians through flood waters that submerged parts of the financial district of Makati on August 20, 2013 in Makati City south of Manila, Philippines. Image credit: Dondi Tawatao/Getty Images)

Disaster 4. In Pakistan, torrential monsoon rains caused significant flooding that affected 5,739 villages. At least 208 people were killed, 63,180 homes were damaged or destroyed, and 1.4 million acres (567,000 hectares) of crops were submerged. The government estimated economic agricultural losses alone at $1.9 billion. Pakistan’s four most expensive weather-related disasters in its history have been floods that occurred in the past four consecutive years. In this photo, Pakistani residents hold onto a rope as they evacuate a flooded area in Karachi on August 4, 2013. Image credit: Asif Hassan/AFP/Getty Images)

Figure 5. Russia experienced its costliest flood disaster in history beginning on August 4, when the Amur and Zeya rivers in the far east of the country along the Chinese border overflowed, flooding 1.7 million acres, damaging or destroying over 11,500 buildings. It was the 4th most expensive natural disaster of any kind in Russian history. These false-color infrared satellite images of Russia’s Amur River taken a little over a year apart show the extent of the extreme flooding that affected the Komsomolsk-on-Amur area (population 500,000) in August 2013. Image credit: NASA.

Disaster 6. A severe weather outbreak in the U.S. Plains and Midwest August 5 – 7 brought baseball sized hail and thunderstorm wind gusts over 80 mph to Minnesota and Wisconsin. Two people were killed, and damage was estimated at $1 billion. In this photo, a severe thunderstorm closes in on Edgemont, South Dakota, on August 7, 2013. Image credit: wunderphotographer ninjalynn.

The world-wide tally of billion-dollar weather disasters so far in 2013 is 25, and the U.S. total is six, according to the August 2013 Catastrophe Report from insurance broker Aon Benfield. This excludes the September Colorado flood, whose damages are preliminarily estimated at $2 billion. Ranked in term of cost, here are the 25 disasters:

1) Flooding, Central Europe, 5/30 – 6/6, $22 billion
2) Drought, Brazil, 1/1 – 5/31, $8.3 billion
3) Drought, Central and Eastern China, 1/1 – 7/31, $6.0 billion
4) Flooding, Calgary, Alberta Canada, 6/19 – 6/24, $5.3 billion
5) Flooding, China, 8/9 – 9/5, $5.0 billion
6) Tornado, Moore, OK, and associated U.S. severe weather, 5/18 – 5/22, $4.5 billion
6) Flooding, China, 7/7 – 7/17, $4.5 billion
8) Flooding, Indonesia, 1/20 – 1/27, $3.31 billion
9) Super Typhoon Utor, China and Philippines, 8/12 – 8/15, $2.6 billion
10) Flooding, Australia, 1/21 – 1/30, $2.5 billion
11) Flooding, Philippines, 8/18 – 8/21, $2.2 billion
12 Tornadoes and severe weather, U.S., 5/26 – 6/2, $2 billion
12) Severe weather, Midwest U.S., 3/18 – 3/20, $2 billion
14) Flooding, Pakistan and Afghanistan, 8/3 – 8/31, $1.9 billion
15) Winter weather, Europe, 3/12 – 3/31, $1.8 billion
16) Drought, New Zealand, 1/1 – 5/10, $1.6 billion
16) Severe weather, U.S., 4/7 – 4/11, $1.6 billion
18) Flooding, Toronto, Canada, 7/8, $1.45 billion
19) Flooding, China, 6/29 – 7/3, $1.4 billion
19) Flooding, China, 7/21 – 7/25, $1.4 billion
21) Flooding, Argentina, 4/2 – 4/4, $1.3 billion
22) Flooding, India and Nepal, 6/14 – 6/18, $1.1 billion
23) Winter weather, U.S. Plains, Midwest, Northeast, 2/24 – 2/27, $1.0 billion
23) Severe weather, U.S. Plains and Midwest, 8/5 – 8/7, $1.0 billion
23) Flooding, Russia, 8/4 – 8/31, $1.0 billion

Neutral El Niño conditions continue in the equatorial Pacific
For the 17th month in row, neutral El Niño conditions existed in the equatorial Pacific during August 2013. NOAA’s Climate Prediction Center (CPC) expects neutral El Niño conditions to last though the winter of 2013 – 2014, and the large majority of the El Niño models also predict that neutral conditions will last through the winter. Temperatures in the equatorial Eastern Pacific need to be 0.5°C below average or cooler for three consecutive months for a La Niña episode to be declared; sea surface temperatures were 0.0°C from average as of September 16, and have been +0.1 to -0.4°C from average since April 1, 2013.

Arctic sea ice falls to 6th lowest August extent on record
Arctic sea ice extent during August was 6th lowest in the 35-year satellite record, according to the National Snow and Ice Data Center (NSIDC). This was the largest August extent since 2009, and a nice change of pace from last year’s all-time record retreat. The Arctic sea ice reached its minimum extent for the year on September 13, and has now begun re-freezing. I’ll have a dedicated post on this, probably on Tuesday.

Quiet in the Atlantic
In the Gulf of Mexico, the tail end of a cold front off the coast of Texas has developed a few disorganized heavy thunderstorms. This disturbance has some modest spin to it, thanks to absorbing Invest 95L on Saturday. However, wind shear is high, 20 – 30 knots, and I don’t expect this disturbance will develop. The disturbance is expected to bring 1 – 3″ of rain to Florida later this week, and on Saturday, the Army Corps of Engineers has re-opened the flood gates on Lake Okeechobee to dump water out of the lake in anticipation of the heavy rains. None the reliable models for tropical cyclone formation is predicting development during the coming five days.

In the Western Pacific, Typhoon Usagi has dissipated after hitting China about 100 miles east-northeast of Hong Kong. The storm is being blamed for at least 25 deaths in China and 2 in the Philippines. Preliminary damage estimates are over $500 million.

Jeff Masters


August Hurricane Potential

Thursday, August 1st, 2013

A massive dust storm that formed over the Sahara Desert early this week has now pushed out over the tropical Atlantic, and will sharply reduce the odds of tropical storm formation during the first week of August. The dust is accompanied by a large amount of dry air, which is making the Saharan Air Layer (SAL) much drier than usual this week. June and July are the peak months for dust storms in the Southwest Sahara, and this week’s dust storm is a typical one for this time of year. Due in large part to all the dry and dusty air predicted to dominate the tropical Atlantic over the next seven days, none of the reliable computer models is predicting Atlantic tropical cyclone formation during the first week of August.

Figure 1. A massive dust storm moves off the coast of Africa in this MODIS image taken at 1:40 UTC July 30, 2013. Image credit: NASA.

Video 1. The predicted movement through August 3 of this week’s Africam dust storm, using the NOAA NGAC aerosol model. Image credit: NOAA Visualization Laboratory.

How dust affects hurricanes
Saharan dust can affect hurricane activity in several ways:

1) Dust acts as a shield which keeps sunlight from reaching the surface. Thus, large amounts of dust can keep the sea surface temperatures up to 1°C cooler than average in the hurricane Main Development Region (MDR) from the coast of Africa to the Caribbean, providing hurricanes with less energy to form and grow. Ocean temperatures in the MDR are currently 0.7°F above average, and this anomaly should cool this week as the dust blocks sunlight.

2) The Saharan Air Layer (SAL) is a layer of dry, dusty Saharan air that rides up over the low-level moist air over the tropical Atlantic. At the boundary between the SAL and low-level moist air where the trade winds blow is the trade wind inversion–a region of the atmosphere where the temperature increases with height. Since atmospheric temperature normally decreases with height, this “inversion” acts to but the brakes on any thunderstorms that try to punch through it. This happens because the air in a thunderstorm’s updraft suddenly encounters a region where the updraft air is cooler and less buoyant than the surrounding air, and thus will not be able to keep moving upward. The dust in the SAL absorbs solar radiation, which heats the air in the trade wind inversion. This makes the inversion stronger, which inhibits the thunderstorms that power a hurricane.

3) Dust may also act to produce more clouds, but this effect needs much more study. If the dust particles are of the right size to serve as “condensation nuclei”–centers around which raindrops can form and grow–the dust can act to make more clouds. Thus, dust could potentially aid in the formation and intensification of hurricanes. However, if the dust acts to make more low-level clouds over the tropical Atlantic, this will reduce the amount of sunlight reaching the ocean, cooling the sea surface temperatures and discouraging hurricane formation (Kaufman et al., 2005.)

Figure 2. Map of the mean summer dust optical thickness derived from satellite measurements between 1979 and 2000. Maximum dust amounts originate in the northern Sahel (15° to 18° N) and the Sahara (18° to 22° N). The Bodele depression in Chad is also an active dust source. Image credit: Evidence of the control of summer atmospheric transport of African dust over the Atlantic by Sahel sources from TOMS satellites (1979-2000), by C. Moulin and I. Chiapello, published in January 2004 in Geophysical Research Letters.

Dust in Africa’s Sahel region and Atlantic hurricane activity
The summertime dust that affects Atlantic tropical storms originates over the southwestern Sahara (18° – 22° N) and the northwestern Sahel (15° – 18° N) (Figure 3.) The dust from the Southwest Sahara stays relatively constant from year to year, but the dust from the Northwest Sahel varies significantly, so understanding this variation may be a key factor in improving our forecasts of seasonal hurricane activity in the Atlantic. The amount of dust that gets transported over the Atlantic depends on a mix of three main factors: the large scale and local scale weather patterns (windy weather transports more dust), how wet the current rainy season is (wet weather will wash out dust before it gets transported over the Atlantic), and how dry and drought-damaged the soil is. The level of drought experienced in the northwestern Sahel during the previous year is the key factor of the three in determining how much dust gets transported over the Atlantic during hurricane season, according to a January 2004 study published in Geophysical Research Letters published by C. Moulin and I. Chiapello. In 2012 (Figure 3), precipitation across the northwestern Sahel was much above average, which should result in less dust than usual over the Atlantic this fall, increasing the odds of a busy 2013 hurricane season.

Figure 3. Rainfall over the Northwest Sahel region of Africa was about 200% of average during the 2012 rainy season. The heavy rains promoted vigorous vegetation growth in 2013, resulting in less bare ground capable of generating dust. Image credit: NOAA/Climate Prediction Center.

Saharan Air Layer Analysis from the University of Wisconsin

Atlantic dust forecast from the Tel-Aviv University Weather Research Center

Dr. Amato Evan published a study in Science magazine March 2009 showing that 69% of the increase in Atlantic sea surface temperatures over the past 26 years could be attributed to decreases in the amount of dust in the atmosphere.

Kaufman, Y. J., I. Koren, L. A. Remer, D. Rosenfeld, and Y. Rudich, 2005a: The effect of smoke, dust, and pollution aerosol on shallow cloud development over the Atlantic Ocean. Proc. Natl. Acad. Sci. USA, 102, 11 207–11 212.

Wang, Chunzai, Shenfu Dong, Amato T. Evan, Gregory R. Foltz, Sang-Ki Lee, 2012, Multidecadal Covariability of North Atlantic Sea Surface Temperature, African Dust, Sahel Rainfall, and Atlantic Hurricanes, J. Climate, 25, 5404–5415.


Siberia heat Wave, South America Cold, Thailand Rains

Sunday, July 28th, 2013

Cold Snap hits southern South America. UPDATE: (and ‘Big Fish in Living Room’ story!)

It has been a wild week for temperature extremes with the amazing heat wave in north central Siberia juxtaposed with an unusual cold spell in portions of Brazil, Bolivia, and Argentina occurring simultaneously almost exactly opposite one another on the planet. Scroll down to end of blog for my fishy story! It actually has some context considering the amazing rainfall record set at Chantaburi, Thailand this past week.

South American cold snap

Between 20-25th July a mass of very cold air suddenly froze a large area of southern South America (where temperatures had been running above average for weeks prior to the abrupt change).

Snow was recorded for the first time since 1996 at Catamarca, Argentina (28°S and located at about 500m/1,650’), and cold rain (temperatures of 5-6C/41°-43°°F) at sea level altitudes like Florianopolis, Brazil. Montevideo, Uruguay also experienced rain with temperatures as low as 3C (37°F). The town of Campos Novos, Brazil (at an elevation of 947m/3,100’) had a high temperature of just 3.6°C (38.5°F) and low of -2.7°C (27.1°F) on July 23rd, a daily average of almost freezing (0.9°C/32.8°F). There was no precipitation at the site that day, if so it probably would have been snow. In fact, a little snow was reported in Brazil in the hills above nearby Curitiba for the first time since 1975.

Snowfall in the mountainous region of Santa Catarina, Brazil is not so unusual. Above is an image of a deep snowfall near Rio Grande do Sul during the cold wave of July-August 2010. Ironically, this occurred at the same time as the famous Moscow heat wave of that summer, a somewhat similar situation as is now occurring. Photographer not identified.

There were incredible temperature contrasts in Bolivia (which isn’t unusual given the complex Andean topography) but what was unusual was that it was actually colder at the low elevations in the Amazonian jungle than in the higher mountainous terrain of the country: temperatures at Bolivian locations above 4000m (13,000’) on 23 July were higher than those in the Bolivian portions of the Amazon jungle at low elevations. For instance, the temperature at Reyes (located at 14°S and 140m/462’ elevation) had a maximum of 9.3C/48.8°F while at El Alto Airport, La Paz (elevation 4,000m/13,200’) the temperature maximum reached 13.9°C (57°F). Temperatures in the Chaco region of Bolivia were remarkably chilly with a reading of -5.8°C (21.6°F) observed at Villamontes.

Some places in the middle of the Andes, protected by mountains on all sides, like Cochabamba didn’t experience a single degree drop in temperature, while low areas experienced drops as high as 22-25°C (40-45F) in 24 hours. In Paraguay sleet was recorded in Itapua and the minimum temperature reached -5.2C (21.6°F) at Prats Gill on 24th, not far from the all-time national record of -7.5C (18.5°F) (also set in Prats Gil) on July 13, 2000

The cold air actually filtered as far north as the western part of the Amazon jungle near the Equator, with 7°C (44.6°F) at Rio Branco, Brazil (10°S latitude) and 16°C (60.8°F) at Leticia, Colombia (4°S latitude). Both are low-level sites in the Amazon Basin.

The most exceptional cold wave, in regard to how north cool air has ever penetrated, was that of July 1975 when air of polar origin reached the Caribbean affecting the whole of South America (including the extreme western part of Amazon in Peru, Brazil, Colombia, Venezuela, the Guyanas, and even Trinidad and Tobago. Unlike other cold waves (such as those of 1955, 1973 and 2010) the July 1975 event didn’t stop south of the Equator, but continued well into the Northern Hemisphere. This remains unique and the only documented occurrence of such an event. The surface high pressure reached 1044 hPa (30.82”) over central South America on July 15, 1975, the highest yet measured (modern records) on the continent (REF: Markgraf, Vera Interhemispheric Climate Linkages p. 37)

500 mb MAP

Surface air temperature anomaly for the week of July 19-24 (top map) and 500 mb height anomalies for the same period (bottom). Note how the cold air over South America is almost exactly on the opposite side of the world from the heat dome over north central Siberia. NCEP/NCAR maps, courtesy of Stu Ostro.

The cold snap this past week was caused by a strong upper-level low centered over the southern third of the continent. Curiously, it has been unusually mild over the portions of Antarctica opposite South America with a high of 7.8C (46.0°F) being recorded at Base Esperanza (63°S), higher than the normal summer average maximum and just 1.5°C less than the Amazonian maximum of Reyes in Bolivia at 14°S latitude!

Meanwhile on the other side of the world…

The unrelenting heat wave in north central Siberia continues with Svetlogorsk (on the Arctic Circle) recording its 13th consecutive day (as of July 26) with temperatures above 30°C (86°F). Meanwhile, all eyes are turning to Western Europe where a potentially historic heat wave is expected to develop this weekend and continue into next week! There is a chance that some all-time national heat records may fall in some countries like Germany, Liechtenstein, Austria, Slovakia, Slovenia, and Hungary when all is said and done.

Phenomenal Rainstorm in Thailand

On a side note, a historic rainstorm has caused serious flooding in portions of southeastern Thailand. Chantaburi picked up 445.7mm (17.55”) of rain on July 23rd with an amazing 385mm (15.16”) of this falling in just 12 hours and an even more amazing 297 mm (11.69”) in just 6 hours! This may be one of the (if not the) heaviest 24-hour rainfall on record for Thailand (previous record was 414.8mm (16.33”) at Ko Samui on March 28, 2011. A famous flood in Bangkok occurred on May 9-10, 1986 when 401.1 mm (15.79”) of rain fell in just 8 hours. The ensuing floods almost cost the mayor (Chamlong) his job.

My ‘fish story’

I lived a few blocks from the Bangkok Met office at the time (during the storm of 1986) on Soi 49 Sukhumvit Rd. and caught a 15″ fish that swam through a break in the screen porch door off my living room which flooded about half a meter deep at one point. My girlfriend at the time and I trapped the sucker hiding under the water-logged couch in the living room. We grilled it later that same day (after the water receded) and it was delicious (no idea what kind of fish it was). I think I must be one of the only people who have caught a large live fish swimming around their living room and then cooked it in their kitchen just 10 feet away hours later :-). I’d love to hear from other WU friends if they have had a similar experience!

METARS for Chantaburi, Thailand July 22-23 when a peak 24-hour rainfall amount of 445.7 mm (17.55”) accumulated, a possible national record. Flooding continues as more rain has since fallen over this region of southeastern Thailand. From OGIMET.

KUDOS: Thanks to Maximiliano Herrera for much of the above information about the cold wave in South America.

Christopher C. Burt
Weather Historian


Overall Weekly Chromoscope

Monday, July 8th, 2013

July 7-13

The theme this week is “of all things…”   And it will definitely be a week of all things, so choose wisely what it is that you are wishing to focus upon.  That can make a big difference this week.


Overall Color for the Week:    Light Green Blue

So, what you thought you knew, what you thought was so reliable, how you created your routine, all those kinds of things are turning out to be not quite as rock solid as you thought.  Just remember that most of the space in an atom is empty, and you might just find yourself staring into a new kind of emptiness this week as the energies begin to pull things apart, as things start tumbling about.  You will find this week can bring you some interesting confrontations, exchanges, conversations with people you know.  The effect of these will be to make you question a lot of the foregone conclusions that you had had.  Also, you might feel yourself spinning a bit off center as friends you thought you knew so well become somehow different.    The long view of all this is to see that things that once seemed so reliable are changing.  Interestingly, your reactions and doubts and questions can be provoked by a seemingly innocent comment.  As for some of the things you used to love, this week you will begin to look at as not quite so desirable.  You may still enjoy them, but you are becoming aware that a lot of the charm of the old stuff is beginning to fade.  This can lead to some deep questioning.  This week, take time to clear your environment through sound, smudge, etc.  Maintain that clarity as it will assist you in taking on a new perspective.  Also stay grounded.  Be centered in your heart.  Act from your core, and in all circumstances, proceed from love.  There is no clearer light.

On the larger scale, the foundations are coming apart in many, many countries.  Things are being seen on the news in obvious cases, but there will much that is not noted.  Some of this can be related to the one-sidedness of the media.  Some can be related to the fact that small movements in the beginning are not seen as having any real significance.  The myopia of the powers that want to be is becoming ever more pronounced.  The financial markets will ride something of a roller coaster this week, but should end basically on a high note as some double-talk announcement is made concerning an issues related to fuel and the environments.  Also the weather will turn wicked in some areas.  There will be unexpected bursts of weather conditions that are out of season, even frightening.  There is more flow within the mantle of the Earth.  It is as though the liquid core is becoming somewhat unbalanced.  This can lead to some unusual effects on the surface and in the seas.  Look for an individual to be arising possibly in the Mid to Far East who is going to have some promises of some kind of salvation, perhaps not reported just yet, but rumored in the social media.  There will be more UFO activity, much caught on camera, and there is the possibility if bot this week, but soon, of some kind of message coming to the Earth from the Galaxy.  Look for more talk of diseases.  Interestingly, none will be linked to the obvious culprits – GMO’s, vaccines, pollution, etc.  It is well to look to local farmers for your produce.  That one time extra-Galactic energy is beginning to exert more of a pull on the planets as a whole and on the Sun in particular.  There can be some weird events relative to planetary motion and solar activity.

It is time for all to be in touch with Gaia, to offer her your support, and to be connected with her at all times.

6/12 Violent Weather

Thursday, June 13th, 2013

It was a wild weather night over much of the Midwest, Great Lakes, and Mid-Atlantic on Wednesday, as tornadoes and an organized complex of severe thunderstorms known as a bow echo brought damaging winds to a large swath of the country. NOAA’s Storm Prediction Center (SPC) logged twelve preliminary reports of tornadoes in Iowa, Illinois, and Ohio, but no injuries or major damage were reported with the twisters. A large area of severe thunderstorms organized into a curved band known as a “bow echo” over Indiana during the evening. The bow echo raced east-southeastwards at 50 mph overnight, spawning severe thunderstorm warnings along its entire track, and arrived in Washington D.C. and Baltimore, Maryland near 9 am EDT Thursday morning. SPC logged 159 reports of high thunderstorm wind gusts of 58 mph or greater in the 26 hours ending at 10 am EDT Thursday morning, and three of these gusts were 74 mph or greater. SPC did not classify this event as a “derecho”, since the winds were not strong enough to qualify. Last year’s June 29, 2012 derecho had 675 reports of wind gusts of 58 mph or greater, with 35 of these gusts 74 mph or greater. Thirteen people died in the winds, mostly from falling trees; 34 more people died from heat-related causes in the areas where 4 million people lost power in the wake of the great storm.

Another round of severe weather is expected over the Mid-Atlantic states Thursday afternoon and evening, and SPC has placed portions of this region in their “Moderate Risk” area for severe weather.

Figure 1. Lightning strikes the Willis Tower (formerly Sears Tower) in downtown on June 12, 2013 in Chicago, Illinois. (Photo by Scott Olson/Getty Images)

Figure 2. An organized line of severe thunderstorms took the shape of a “bow echo” over Indiana last night, triggering severe thunderstorm warnings along the entire front of the bow.

Figure 3. Severe weather reports for the 24 hours ending at 8 am EDT June 13, 2013, from SPC.

Big wind in the Windy City
I watched with some trepidation Wednesday evening as a large tornado vortex signature on radar developed west of Chicago, heading right for one of the most densely populated areas in the country. Fortunately, the storm pulled its punch, and Chicago was spared a direct hit by a violent tornado. But what would happen if a violent, long-track EF4 or EF5 tornado ripped through a densely populated urban area like Chicago? That was the question posed by tornado researcher Josh Wurman of the Center for Severe Weather Research in Boulder and three co-authors in a paper published in the January 2007 issue of the Bulletin of the American Meteorological Society. Their astonishing answer: damage of $40 billion and 13,000-45,000 people killed–the deadliest natural disaster in American history, eclipsing the Galveston Hurricane (8,000 fatalities.)

Figure 4. Tornadoes to affect the Chicago area, 1950-2005. Background image credit: Google Earth. Tornado paths: Dr. Perry Samson.

Huge tornado death tolls are very rare
A tornado death toll in the ten of thousands seems outlandish when one considers past history. After all, the deadliest tornado in U.S. history–the great Tri-state Tornado of March 18, 1925–killed 695 people in its deadly rampage across rural Missouri, Illinois, and Indiana. That was before the advent of Doppler radar and the National Weather Service’s excellent tornado warning system. In fact, there has only been one tornado death toll over 100 (the 158 killed in the Joplin, Missouri tornado in 2011) since 1953, the year the NWS began issuing tornado warnings. Chicago has been hit by one violent tornado. On April 21, 1967 a 200-yard wide F4 tornado formed in Palos Hills in Cook County, and tore a 16-miles long trail of destruction through Oak Lawn and the south side of Chicago. Thirty-three people died, 500 more were injured, and damage was estimated at $50 million.

Figure 5. Wind speed swaths for the 1999 F5 Mulhall, Oklahoma tornado if it were to traverse a densely populated area of Chicago. Units are in meters/sec (120 m/s = 269 mph, 102 m/s = 228 mph, and 76 m/s = 170 mph). Winds above 170 mph usually completely destroy an average house, with a crudely estimated fatality rate of 10%, according to Wurman et al.. Insets x, y, and z refer to satellite photo insets in Figure 2. Image credit: Bulletin of the American Meteorological Society.

Figure 6. Aerial photographs from Google Earth of densely populated area of Chicago (insets x, y, and z from Figure 5) These areas contain mainly single-family homes, with housing units densely packed on small lots. A mixture of three-story apartments and single-family homes is typical across the Chicago metropolitan area and many older cities such as New York City and Detroit. At lower right is a photo of Moore, OK, showing lower density housing like the 1999 Bridgecreek-Moore tornado passed through.

The paper by Wurman et al., “Low-level winds in tornadoes and the potential catastrophic tornado impacts in urban areas” opens with an analysis of the wind structure of two F5 tornadoes captured on mobile “Doppler on Wheels” radar systems–the May 3, 1999 Bridgecreek-Moore tornado, which hit the southern suburbs of Oklahoma City, and the Mulhall, Oklahoma tornado of the same day, which moved over sparsely populated rural regions. The Bridgecreek-Moore tornado had the highest winds ever measured in a tornado, 302 mph. Winds of EF4 to EF5 strength (greater than 170 mph) are capable of completely destroying a typical home, and occurred over a 350 meter (1150 foot) wide swath along this tornado’s path. The Mulhall tornado had weaker winds topping out at 245-255 mph, but had EF4 to EF5 winds over a much wider swath–1600 meters (one mile).

The F4 to F5 winds of the Bridgecreek-Moore tornado killed 36 people. Given the population of the area hit, between 1% and 3% of the people exposed to these winds died. The authors thought that this number was unusually low, given the excellent warnings and high degree of tornado awareness in Oklahoma’s population. They cited the death rate in the 1998 Spencer, South Dakota F4 tornado that destroyed 30 structures and caused six deaths, resulting in a death rate of 6% (assuming 3.3 people lived in each structure). There are no studies that relate the probability of death to the amount of damage a structure receives, and the authors estimated crudely that the death rate per totally destroyed structure is 10%. This number will go down sharply if there is a long warning time, as there was in the Oklahoma tornadoes. If one takes the Mulhall tornado’s track and superimposes it on a densely populated region of Chicago (Figure 5), one sees that a much higher number of buildings are impacted due to the density of houses. Many of these are high-rise apartment buildings that would not be totally destroyed, and the authors assume a 1% death rate in these structures. Assuming a 1% death rate in the partially destroyed high-rise apartment buildings and a 10% death rate in the homes totally destroyed along the simulated tornado’s path, one arrives at a figure of 13,000-45,000 killed in Chicago by a violent, long-track tornado. The math can applied to other cities, as well, resulting in deaths tolls as high as 14,000 in St. Louis, 22,000 in Dallas, 17,000 in Houston, 15,000 in Atlanta, and 8,000 in Oklahoma City. Indeed, the May 31, 2013 EF5 tornado that swept through El Reno, Oklahoma, killing four storm chasers, could have easily killed 1,000 people had it held together and plowed into Oklahoma City, hitting freeways jammed with people who unwisely decided to flee the storm in their cars. The authors emphasize that even if their death rate estimates are off by a factor ten, a violent tornado in Chicago could still kill 1,300-4,500 people. The authors don’t give an expected frequency for such an event, but I speculate that a violent tornado capable of killing thousands will probably occur in a major U.S. city once every few hundred years.


The View for the Week

Monday, June 10th, 2013

June 9-16

The theme this week is twins and twinning.  Things that happen once will happen again, and while there are certain things that you cannot control, there are other things you can.


Overall Color for the Week:    Apricot Orange

This week marks a transition on all levels, so it is best to be ready for anything.  You can find some shake-ups and mix-ups in relationships, jobs, emotional levels, etc.  It is a good idea to have back-up plans.  Furthermore, you must be ready for just about anything, so take stuff in stride and do not allow yourself to get overly excited about the unexpected that falls into your path.  Your perspectives are changing and trying to see new stuff with old vision is not going to work.  It can leave you confused and angry.  This is not a week for attempting to place a round peg in a square hole.  This is a week for being present in what you do, making no judgments, and getting rid of a lot of those preconceived notions.  There can be some emotional upsets as some people are showing themselves unable o deal with the energetic changes and they are choosing ways to deal with them that perhaps you would not condone.  You cannot make up other’s minds for them.  This is a week for knowing that allowing is the proper mode of response.  You can be WHO you are in everything while at the same time honoring the choices others make.  This is important to remember.  Take care in traffic and in dealings with strangers.  There is a lot of fire in the air right now, and people can overreact.  It is important to be at one with your choices and to know that you have a deep inner wisdom.  Connect with the deep inner knowing of your heart center.  Stay within your core, ground and align every morning before taking on the day. It is also well to be alert to the messages you are receiving from your body.  This is a good time to make sure that you have stocked up on things like candles, batteries, bottled water, and non-perishable foods.  There is a degree of uncertainty in the electric grid right now and for some time to come.  If you couple that with some of the solar storms that are beginning and will continue for the next few months, there can be challenges to your usual lifestyle as well as to your electronics.


On the larger scale the transitions continue.  There are angry people in power who can no longer ‘keep a lid on it’.  You will be seeing the results of this as the week progresses.  There are going to be a number of things thrown, like a net, upon people in general, upon the grassroots, but they have not take into account that people are fed up.  They have had enough.  Like in Turkey, these kinds of grassroots movements are growing, are spreading.  It should be interesting to see what this all brings forth. Women especially in countries in which they have been oppressed, even though the media might tell you they are not oppressed, will be making their power felt.  India is in the balance.  Interesting, one of the oldest civilizations, with a story mired and secreted.  Things are boiling up from beneath.  There will be a general movement in consort with the Earth energies that will bring forth many unexpected results.  The weather is wafting, wafting, and will hit here and there without program, without prediction. This can lead to craziness in meteorological areas.  There is something brewing in the Gulf.  It is a dark night.  It can make itself felt this week, but may not materialize for some time.   There is something coming onto the scene.  It is not yet formed.  Also look to the skies.  There is some kind of movement happening within the galactic plane.

More WIld Weather for the Mid-West

Friday, May 31st, 2013

It was yet another active day for tornadoes, flooding, and severe thunderstorms in the Midwest on Thursday, with NOAA’s Storm Prediction Center (SPC) logging 16 preliminary tornado reports. Twisters touched down in Oklahoma, Arkansas, and Illinois. The tornadoes missed heavily populated areas for the most part, but seven people were injured in Arkansas in two separate tornadoes, and two other people were hurt by lightning. The severe weather forced organizers of the outdoor Wakarusa Music Festival north of Ozark, Arkansas to delay the start of the festival. The band “Widespread Panic” was one of the groups scheduled to perform, leading to an Associated Press headline from yesterday titled, “Nine hurt in Arkansas storm; Widespread Panic delayed.” Heavy rains from this week’s thunderstorms have pushed the Mississippi River to major flood stage at most places from Burlington Iowa to Quincy Illinois, and the river is expected to crest near major flood stage at St. Louis early next week. In Iowa, the Cedar River at Cedar Falls, the Iowa River at Marengo, and the Skunk River near Sigourney and at Augusta are also in major flood. The latest forecast from NOAA’s Storm Prediction Center calls for a “Moderate Risk” of severe weather today (Friday) over much of Oklahoma and Southwest Missouri, including Oklahoma City and Tulsa in Oklahoma, and Joplin, Missouri, with the potential for several strong EF-2 and EF-3 tornadoes.

Figure 1. Lightning strike from a severe thunderstorm near Guthrie, Oklahoma on May 30, 2013, as photographed by KFOR-TV. (AP Photo/KFOR-TV)

Figure 2. Severe weather outlook for Thursday, May 30, calls for a “Moderate Risk” of severe weather over much of Oklahoma and Southwest Missouri, including Oklahoma City and Tulsa in Oklahoma, and Joplin, Missouri. You can follow today’s severe weather outbreak from our Severe Weather page.

A mostly quiet year for violent tornadoes
After a very quiet March, April, and first half of May, the U.S. tornado season has become very active during the last half of May, and is beginning to catch up to normal. TWC’s tornado expert Dr. Greg Forbes has a preliminary count of 181 tornadoes for the month of May, through May 29, which is 35% below the 10-year average of 279 through May 29th. May 2012 had only 121 tornadoes. The 2013 tornado tally has risen significantly in the last half of May, due to 7 of the last 15 days having above-average numbers of tornadoes. Fortunately, we are well below-average for strong and violent EF-3, EF-4, and EF-5 tornadoes so far in 2013. According to NOAA, the U.S. has averaged 43 EF-3 or stronger tornadoes per year during the period 1954 – 2012. With tornado season nearly half over, only twelve EF-3 and EF-4 tornadoes have been recorded so far in 2013. An average year should have had at least twenty of these tornadoes by this point in the year. Here are the twelve EF-3 and stronger tornadoes so far in 2013, as detailed in Wikipedia’s excellent Tornadoes of 2013 page:

EF-5, May 20, Moore, Oklahoma. 24 deaths, 377 injuries, $2 billion in damage.
EF-4, May 28, Ottawa County, Kansas. Intensity based on mobile Doppler radar data. See the Capital Weather Gang’s description of this tornado.
EF-4, May 19, Shawnee, Oklahoma. 2 deaths, 6 injuries.
EF-4, May 15, Granbury, TX. 6 deaths, 24+ injuries.
EF-4, May 18, Rozel, Kansas.
EF-4, February 10, Hattiesburg, MS. 0 deaths, 82 injuries.
EF-3, Corning, KS, May 28.
EF-3, May 27, Lebanon – Esbon, KS. 1 injured. Wind gust of 175 mph measured by TIV2 intercept vehicle.
EF-3, May 15, Cleburne, TX. No deaths or injuries.
EF-3, January 30, Adairsville, GA. 1 death, 17 injuries, 363 buildings damaged or destroyed.
EF-3, April 11, Kemper County, AL. 1 death, 9 injuries.
EF-3, May 19, Luther – Carney, Oklahoma.

Figure 3. The annual number of EF-3 and stronger tornadoes, 1954 – 2012. The greatest number of these dangerous tornadoes was 131 in 1974, the year of the notorious “Super Outbreak.” The minimum was just 15, set in 1987. The average is 43 per year. Image credit: NOAA.

Video 1. Impressive 2-minute timelapse of the Bennington, Kansas wedge tornado of May 28, 2013, as filmed by the Aussie Storm Chasers. As discussed in an excellent blog post by Jason Samenow of the Capital Weather Gang, the violent EF-4 tornado stood still for nearly an hour, and had wind gusts as high as 264 mph at an altitude of 300 feet measured by Doppler on Wheels.

Remains of Hurricane Barbara bringing heavy rains to Mexico
Hurricane Barbara died on Thursday as it attempted to cross Mexico’s Isthmus of Tehuantepec into the southernmost Gulf of Mexico. While there is no low level circulation apparent on satellite loops this Friday morning, there is a bit of spin at middle levels of the atmosphere, and the remains of Barbara are kicking up some heavy thunderstorm activity over the southernmost Gulf of Mexico and adjacent land areas of Mexico. Wind shear is a high 20 knots in the region, and the area of disturbed weather is quite small, so I don’t expect any development to occur over the next few days. Wind shear is predicted to remain high over the Gulf of Mexico for the next six days, and none of the reliable computers models is calling for tropical cyclone development in the Atlantic during that period. Late next week, wind shear is predicted to drop, and there is a better chance for tropical cyclone development in the Gulf of Mexico or Western Caribbean. Both the GFS and ECMWF models suggest that a strong tropical disturbance with heavy rains may affect Mexico’s Yucatan Peninsula, Western Cuba, and the Southwest Florida by Friday next week.

Figure 4. Remains of Hurricane Barbara in the southernmost Gulf of Mexico as seen by MODIS at 12:05 pm EDT Thursday, May 30, 2013. Barbara had just been declared dead one hour prior to this photo. Image credit: NASA.

Saturday, June 1, is the first day of hurricane season, and I’ll post a quick look at what we might expect to see in June.