El Niño Brings Wet Summer to Plains; Western Drought Continues
by Becky Oskin, Senior Writer | May 21, 2015
Forecasts for June, July and August in the United States suggest temperatures will be cooler than usual in the central Plains.
Credit: NOAA
The West can expect its warm and dry weather to continue through the summer, while the central Plains will be relatively cool and wet, according to a summer forecast released today (May 21).
The East will be slightly warmer than average, and drought will intensify in the Northeast and the Pacific Northwest, a pattern that’s typical of El Niño summers, the National Oceanic and Atmospheric Administration said.
Texas and Oklahoma have already felt the force of El Niño-influenced weather, NOAA said in a briefing today. Both states were in a severe drought last year, but this spring, drenching rainstorms refilled the states’ parched reservoirs to near capacity. Kentucky also saw a soaking spring, recording its second wettest April on record. “This pattern is partially the effect of El Niño conditions,” said David Unger, a forecaster with NOAA’s Climate Prediction Center.
The Texas drought began in October 2010 and was the second-driest spell in the state’s history, said Victor Murphy, a program manager for the National Weather Service’s Southern Region. “It looks like the Texas drought is pretty much over,” Murphy said. [The 5 Worst Droughts in US History]
In summer, a strong El Niño often steers heavy rainstorms toward the southern Plains states and the intermountain West, including Texas, Oklahoma, Colorado, Arizona and New Mexico. However, the summer forecast calls for dry conditions in the West and Alaska, Unger said.
An El Niño also tends to tamp down Atlantic hurricane activity and boost Pacific hurricanes; NOAA plans to release its hurricane forecast on May 27.
The El Niño is a cyclic climate phenomenon that involves both the ocean and the atmosphere. One of its hallmarks is warmer-than-average sea-surface temperatures in the tropical Pacific Ocean. Although the El Niño fizzled last winter, the pool of warm water stuck around this spring and strengthened into a full-blown event.
With an El Niño brewing in the Pacific, the warm tropical ocean surface has been helping set new global heat records this year. Global temperatures in April 2015 were the fourth warmest on record since 1880, said Jake Crouch, a NOAA climatologist. And the first four months of 2015 shattered old heat records.
During January through April, the average temperature across land and ocean surfaces was 1.44 degrees Fahrenheit (0.8 degrees Celsius) above the 20th-century average. This surpassed the previous record, set in 2010, by 0.13 F (0.07 C).
“2015 is very warm compared to other years,” Crouch said. “It has been really quite a bit ahead of the pack.”
Atlantic’s First Invest of the 2015, 90L, Organizing Over the Bahamas
By: Jeff Masters and Bob Henson , 3:50 PM GMT on May 06, 2015
2015: May 6
2014: June 4
2013: May 18
2012: February 5
2011: March 10
2010: May 24
2009: May 18
2008: May 31
2007: May 8
2006: June 10
Figure 1. Latest satellite image of Invest 90L.
Satellite loops show heavy thunderstorms between the Southeast coast of Florida and the Northwest Bahamas in association with 90L increased on Wednesday morning, but there was no evidence of an organized surface circulation trying to form. Long-range radar out of Melbourne, Florida showed no low-level spiral bands trying to form, and the activity was not well-organized. Wind shear was a moderate to high 15 – 25 knots. Water vapor satellite loops show a large area of dry air to the west of 90L over Florida and the Gulf of Mexico, and this dry air is retarding development, thanks to strong upper-level winds out of the west driving the dry air into the core of 90L. Ocean temperatures were near 26°C (79°F), which is about 1.7°C (3°F) above average for this time of year, and just at the limit of where a tropical storm can form. The Hurricane Hunter mission scheduled for Wednesday afternoon was cancelled, and has be re-scheduled for Thursday afternoon, if necessary.
Figure 2. Wind forecast for Saturday, May 9, 2015 at 11 am EDT made by the 00Z Wednesday run of the European model. The model is predicting a subtropical depression to be off the coast of the Southeast U.S.
Forecast for 90L
The 8 am EDT run of the SHIPS model predicted that wind shear over 90L would fall to the moderate range, 10 – 20 knots, on Thursday and Friday, which should allow 90L to approach subtropical depression status by Friday at the latest. Phase space diagrams from Florida State University from Wednesday morning’s 06Z run of the GFS model support the idea that this system could be a subtropical or tropical system by Friday. Ocean temperatures fall to about 25°C (77°F) in the waters off of the North Carolina coast, so the farther north the storm wanders, the tougher time it will have developing tropical characteristics–though if the storm manages to find a sweet spot over the core of the warm Gulf Stream current, it has better odds of development. Steering currents are weak over the waters off the Southeast U.S. coast, so expect a slow and erratic motion for 90L. The Wednesday morning 00Z runs of our two top models for predicting tropical cyclones tracks, the European and GFS models, both showed the system making landfall this weekend, with the GFS model predicting landfall in South Carolina on Saturday, and the European model taking the storm ashore in North Carolina on Sunday. Beginning on Friday, coastal regions of both of these states can expect heavy rains and high surf causing rip currents and coastal erosion. Note that the west side of 90L will be weaker and drier, due to the dry air to the west of the storm, and the heaviest rains and stongest winds of 90L will be on the east side of the storm, over North Carolina. In their 8 am EDT Tropical Weather Outlook, NHC gave the disturbance 2-day and 5-day odds of development of 60%, respectively.
Figure 3. Latest projected track of Typhoon Noul from the Joint Typhoon Warning Center (JTWC); a time of 9:00 p.m. JST Wednesday is 1200 GMT or 8 am EDT.
Typhoon Noul posing an increased threat to northern Philippines
After dumping more than 10 inches of rain at Yap International Airport, Category 1 Typhoon Noul is on its way toward the northern Philippines. Noel is gradually intensifying, with sustained winds of 90 mph reported at 8 am EDT (1200 GMT) Wednesday. Satellite loops show that the storm’s center is obscured by central dense overcast, but microwave data obtained by satellite shows that an open eye is already present. Noel is well structured and passing over warm waters, with only weak to moderate wind shear, so continued strengthening into a Category 4 storm is expected. Noel will encounter a trough as it approaches the Philippines, which may force the storm to recurve before making landfall there. However, model guidance has been trending westward, albeit with some uncertainty, and the official Joint Typhoon Warning Center track (see Figure 3) now brings Noul ashore along the northeast coast of Luzon, the largest and northernmost island of the Philippines. Noel is expected to peak in intensity just a few hours before approaching Luzon, with sustained winds of 105 knots (120 mph) projected by the JTWC near landfall. The northeast part of Luzon is mountainous, which could increase the risk for very heavy rains as Noul moves onshore or nearby, although a grazing landfall would put most of Luzon on the weaker western side of the circulation. Noul will be referred to as Dodong in the Philippines’ naming system.
Another tropical system, Invest 93W, is organizing to the east, and is likely to develop late this wee. It is too soon to know what its chances are of affecting the Philippines or Japan next week.
An exceptionally busy early portion of typhoon season
Noul’s formation date of May 3 marks the second earliest appearance on record for the Northwest Pacific’s sixth named storm of the year, according to statistics of the Japan Meteorological Agency’s database from 1951 – 2015 maintained by Digital Typhoon. The average is 1.8 storms before May 8. The record is held by 1971, when the sixth named storm of the year (Babe) formed on May 3, six hours earlier than Noul’s formation time. Noul will be the second tropical cyclone to affect the Philippines so far in 2015. The first was Tropical Storm Maysak, which hit the Philippines exceptionally early in the season–during Easter weekend, April 4 – 5. Fortunately, Maysak was weakening rapidly as it made landfall, and no deaths or significant damage were reported (though four people were injured after huge waves generated by Maysak hit them while they were taking selfies along the shoreline of Dipaculao town in Aurora province on April 4.)
The U.S. Climate of 2014: Remarkable Hot, Cold, Wet and Dry Extremes
By: Bob Henson , 4:17 PM GMT on January 12, 2015
How you experienced the climate of 2014 depended a great deal–by some measures, more than any year in U.S. history–on where in the nation you happened to be. This was made abundantly clear in the full 2014 report on U.S. temperatures and precipitation, released this morning by NOAA’s National Climatic Data Center (NCDC). When looking at the entire contiguous 48 states, the annual rankings aren’t especially striking: the year placed 34th warmest and 40th wettest out of 120 years of data. The overall warmth comes as no surprise, given that every year since 1996 has placed above the nation’s long-term temperature average.
These unremarkable statistics obscure the real story of 2014: the titanic contrast between a parched, scorched West (especially California, where the heat left all-time records in the dust), a very warm New England and Florida, and a much cooler area in between, with some months at or near all-time record lows in states stretching from the Great Lakes to the Gulf Coast.
NCDC’s state-by-state map of 2014 temperature rankings (see Figure 1) tells the tale vividly. California, Nevada, and Arizona all saw their hottest year on record, going back to 1895. The year placed among the top-twenty warmest in most of the other western states, as well as in Maine. At the same time, a corridor of seven central states–Louisiana, Arkansas, Missouri, Illinois, Indiana, Wisconsin, and Michigan–saw 2014 place among their top-ten coolest years.
Figure 1. State-by-state rankings for annual average temperature in 2014. A ranking of 1 denotes the coolest year in the 120-year record, while 120 denotes the warmest. Image credit: NOAA National Climatic Data Center.
Another way to look at these contrasts is through the statistical lens of NCDC’s Climate Extremes Index. The CEI is made up of five different indicators that show how much of the nation experienced a particular type of weather extreme. Two of the indicators relate to the percentage of the nation experiencing either unusually warm or cold daily highs or unusually warm or cold daily lows (averaged from month to month in both cases). Some 23.2% of the contiguous U.S. qualified as having unusually warm highs for the year, which is the 18th-largest percentage out of the past 120 years. The percentage of the nation experiencing unusually cold highs (18.6%) ranks 21st. What’s especially intriguing is that this is the first year on record that both the warm-high and cold-high percentages have exceeded 15%, a sign of how difficult it is to sustain such wildly divergent temperature regimes between the Pacific and Atlantic for an entire year. Overall, using all the elements of the CEI, 2014 ranked as the 9th most extreme year since 1910 (excluding the impact of tropical cyclones), or the 19th most extreme when including the impact of tropical cyclones. Interestingly, for the second year in a row, daily record low minimums occurred more often than daily record high maximums (20,937 vs. 14,122). This trend is unlikely to continue; the opposite occurred for a number of years prior to 2013.
The Midwest and Southern chill established itself early, with a series of cold-air outbreaks that came to be associated with the term “polar vortex”. (That phrase’s meaning became so mangled in press coverage and popular understanding that it led the American Meteorological Society to update its official definition). Colder-than-average weather persisted across much of the central and east until May and June, which came in above average in most states. Midsummer saw a return to strikingly cool weather across the nation’s heartland. The pattern was even more unusual–and pleasant for millions of residents–in that it was accompanied by relatively dry weather. It was the coolest July on record for Arkansas and Indiana, and the second coolest in Illinois, Mississippi, and Missouri.
After the west-to-east contrast eased somewhat in late summer and early autumn, a record-setting Arctic outbreak in November reestablished the cold-east/warm-West pattern once more, leading to the second-coldest November on record for Alabama and Mississippi. Finally, just in time for the holidays, the 48 states got on the same temperature track, with unusual mildness nationwide producing the second-warmest December on record. Alaska joined in as well: the state’s 19 first-order weather stations were a collective 7.5°F above average for the month, and Fairbanks saw its second warmest December in its 111-year record, according to the Alaska Climate Research Center. Overall, 2014 was Alaska’s warmest year in a 97-year period of record, with an average statewide temperature 4°F above the average for 1971-2000.
Figure 2. State-by-state rankings for annual average precipitation in 2014. A ranking of 1 denotes the driest year in the 120-year record, while 120 denotes the wettest. Image credit: NOAA National Climatic Data Center.
Days of deluge
The national precipitation ranking and the state-by-state maps (see Figure 2) hide some dramatic contrasts as well. Most of the year was extremely dry in California, even though the state ended up near average for total annual precipitation. Elsewhere, intense bouts of precipitation made the headlines in a number of spots. Day after day of extreme rain pushed the June precipitation totals across parts of the Midwest into record-obliterating territory. Sioux Falls, South Dakota, received 13.70″ for the month, with more than half of that falling in just three calendar days. The town of Canton broke South Dakota’s monthly precipitation record with 19.65″.
Several major one-day rainfall events emerged from an extremely moist summer air mass that slathered much of the eastern United States in early August. Detroit experienced its second-heaviest calendar-day rainfall (4.57″) on August 11, as did Baltimore on August 12 (6.30″). Even more impressive was the 13.57″ that fell at Islip, New York, on August 11-12. The downpour set a new state record for 24-hour rainfall, which is especially noteworthy given that a tropical cyclone was not directly involved. A few weeks later, not to be outdone, Phoenix set an all-time calendar-day rainfall record on September 8 with 3.29″, fed by deep moisture from ex-Hurricane Norbert.
Figure 3. A highway in Brentwood, New York, resembles an infinity pool after more than a foot of rain fell across parts of central Long Island on August 11-12, 2014. WunderPhoto credit: Hurricane765.
The NCDC’s Climate Extremes Index lends some statistical backing to this anecdotal portrait of deluges. The “extremes in 1-day precipitation” indicator measures how much precipitation for the year fell in calendar days with extreme amounts (equal to the wettest tenth percentile of all days). Some 15.3% of the nation saw a much-above-average number of days fall into this category for 2014. That’s a bit less than the 2013 value of 16.3%, but still enough to put it at 11th highest of the past 120 years. Notably, all of the top seven years for this index, and 13 of the top 15 years, have occurred since 1990.
Wet days getting wetter, and droughts getting hotter
The recent uptick in extreme one-day precipitation totals across the nation is consistent with more than a decade of research showing that many parts of the world, including the United States, are seeing their heaviest bouts of rain and snow getting even heavier over time. This conclusion was reinforced on a national and regional scale in the 2014 U.S. National Climate Assessment and on a city-by-city scale in a study by Brian Brettschneider (Boreas Scientific LLC) highlighted by Weather Underground blogger Chris Burt last August. The result is also consistent with the basic concept that a warming planet will see an increase in hydrologic contrasts, as warmer temperatures allow for more water to evaporate from lakes, oceans, and plants–helping boost the output of rainstorms and snowstorms–while sucking more water from already-parched land, intensifying the effects of drought.
This process is vital to keep in mind when taking stock of the California drought, arguably the nation’s most catastrophic weather event of the year. Although calendar year 2013 was the state’s driest on record, the water year of 2013–14 (July to June) placed third driest. (Water years are the most commonly used index for assessing California precipitation, which occurs mainly in the fall through spring). A NOAA-led study released in December found that the severity of drought conditions over the last three water years–looking only at rainfall–is within the realm of natural variability, with 1974–75 to 1976–77 even drier than the period from 2011–12 to 2013–14. However, the temperatures associated with the more recent drought went well beyond what one would expect from historical analogs (see Figure 4), which has made the impact on ecosystems, agriculture, and people even more severe. The NOAA study acknowledged, “record-setting high temperature that accompanied this recent drought was likely made more extreme due to human-induced global warming.” In a similar fashion, the intense Texas drought of 2011 was associated with all-time temperature records established during the brutal, more prolonged droughts of the 1930s and 1950s. As states and regions consider how best to adapt to drought conditions in the future, they would be well advised to consider the possibility that temperatures during drought periods could soar beyond anything observed in more than a century of experience.
Figure 4. The annual average temperature for California in 2014 came in far above the previous record for the last 120 years, and it was roughly 4°F above the 20th-century average. Image credit: NOAA National Climatic Data Center.
Figure 5. A lone weed grows on an unplanted field on August 21, 2014 in Firebaugh, California. As the severe California drought continued for a third straight year, Central California farming communities struggled to survive, with an unemployment rate nearing 40 percent in the towns of Mendota and Firebaugh. Photo credit: Justin Sullivan/Getty Images.
After basking in record warm temperatures in the 60s and 70s on Monday, the Northeast U.S. is bracing for a Wednesday winter onslaught, as a significant Nor’easter will bring heavy snows to the roads at the same time that millions of people hit the roads in advance of the Thanksgiving holiday. The unwelcome storm will form off the coast of South Carolina Tuesday night and track north-northeastward, parallel to the coast, on Wednesday. Snow will begin in the Southern Appalachians late Tuesday night and spread northeastwards on Wednesday. Areas to the east of the I-95 corridor will start off with heavy rain, but the rain will transition to wet, heavy snow on Wednesday afternoon as cold air spills southwards along the coast. Little or no accumulation is likely in Washington D.C., which hit a pleasant 74°F on Monday. The story is different, though, in Philadelphia, where a Winter Storm Watch for 2 – 3 inches of snow was posted on Monday–even as the temperature rose to a record high for the date of 72°F. Higher snowfall amounts of 4 – 8″ are possible in New York City, which also experienced a record high on Monday–64°F at Kennedy Airport. Boston will also be severely impacted beginning late Wednesday afternoon, with snows of 4 – 6″ possible. Portland, Maine, which hit a record 63°F on Monday, is under a Winter Storm Watch for 4 – 8″ of snow. The heaviest snows will come Wednesday afternoon into Wednesday evening in the big cities, and may take some time to accumulate on the roads due to stored heat from the warm temperatures of the past few days. Traveling earlier in the day Wednesday is definitely recommended if you have the flexibility, as road conditions will steadily deteriorate through the afternoon into evening. The worst conditions will be experienced inland from the coast, where widespread snow amounts of 6 – 12 inches are likely along a swath from Northeast Pennsylvania and Northwest New Jersey into Maine, including Hartford, Connecticut and central Massachusetts cities like Worcester. As usual with a storm of this nature, small changes in the forecast track of the system can cause large changes in the amount of snowfall near the coast, so stay tuned to the latest forecasts.
Figure 1. Snowfall forecast for the New York City area made on Tuesday morning, November 25, 2014. Image credit: NWS New York City.
Figure 2. Snowfall forecast for the Boston area made on Tuesday morning, November 25, 2014. Image credit: NWS Boston.
Figure 3. Snowfall forecast for the Philadelphia area made on Tuesday morning, November 25, 2014. Image credit: NWS Philadelphia.
Air travel will be heavily impacted
Heavy rains will cause flight delays at the large airports of the Northeast beginning Wednesday morning, and these delays will increase on Wednesday afternoon as the snow flies. All of the major airlines are allowing people to change their tickets for free at the airports expected to be affected by Wednesday’s storm; here is one such list of cities from United:
Albany, NY (ALB)
Allentown, PA (ABE)
Atlantic City, NJ (ACY)
Baltimore, MD (BWI)
Bangor, ME (BGR)
Boston, MA (BOS)
Buffalo, NY (BUF)
Burlington, VT (BTV)
Harrisburg, PA (MDT)
Hartford, CT (BDL)
Manchester, NH (MHT)
New York/Newark, NJ (EWR – Liberty)
New York, NY (JFK)
New York, NY (LGA – LaGuardia)
Philadelphia, PA (PHL)
Portland, ME (PWM)
Providence, RI (PVD)
Rochester, NY (ROC)
Syracuse, NY (SYR)
Washington, DC (DCA – National)
Washington, DC (IAD – Dulles)
White Plains, NY (HPN)
Wilkes-Barre/Scranton, PA (AVP)
CRISTOBAL intensified into a hurricane early last night as wind shear eased a bit, and outflow improved somewhat to the North and south. Shear remains relatively high near 20Kts, and with no improvement in the outflow pattern above the storm expected and the proximity to drier to its west – significant intensification appears unlikely as the 988mb storm moves Northward during the next 2 days along the western periphery of the sub-tropical (Bermuda) High centered in the central Atlantic. All the models are now in excellent agreement on both the track and intensity forecast for CRISTOBAL, and except for large waves and localized rip currents along the east coast – CRISTOBAL will have no impact on the US mainland
INVEST 97L POSES A POTENTIAL THREAT OF DEVELOPMENT THIS WEEKEND
Although NHC dropped 97L overnight, this system is now BACK on the NHC home page chart, most likely due to several global models now forecasting it to develop this weekend as it approaches the Leeward Islands – with the GFS and a few other models tracking it as a cyclone into the southeast coast of the US mainland late next week. Because NHC ‘dropped’ the system over night, none of the specialized hurricane models we executed during the 12Z cycle run. However, the models will almost certainly be initialized for the 18Z cycle run later today. That said – the system is currently surrounded by dry and somewhat stable air with no significant outflow signature seen on SAT imagery at this time; so development, if any, will be quite slow for the next 72 hours.
STRONG DISTURBANCE STILL WESTBOUND OVER AFRICA
Finally, the strongest African tropical disturbance of the season is now located over west-central Africa with a long history of deep convection and a well established rotation in low to mid levels. The disturbance is now moving slowly westward, and is expected to emerge off the west African coast this weekend. Some model projections forecast this system to gradually intensify next week – but also put it on a more Northwesterly track next week – implying this system will start heading out to sea by later next week.
Fig 1: Early morning VIS imagery shows the center of CRISTOBAL on the NW side of deep convection moving Northward at about 5Kts (based on the last 6 hours of RECON/SAT image tracking). The overall satellite signature is highly unusual for a tropical cyclone, especially of hurricane intensity – with the system appearing to be along the southern edge of a mid-latitude frontal boundary. In some respects, that is exactly what has occurred over the last 24 hours, with the southward plunge of well defined dry air surge to the immediate west of the cyclone, leading to a ‘linear’ type orientation of convection extending from well north of CRISTOBAL southward to the storm itself. There is a small possibility that this ‘dynamic’ boundary actually helped intensify the cyclone, despite the moderate shear and dry air that is just west of the storms core circulation. Normally, dry air this close to a relatively weak and sheared system like we had would weaken or totally halt intensification – but in this case (the first I’ve ever seen) – the opposite occurred. It’s worth noting that the dry air surge extended into the northern GOM as well – triggering a line of strong convection there.
Fig 2: The above overview of the tropical Atlantic shows a significant tropical wave/disturbance that was (and now again, is) 97L approaching 50W, and is still westbound at ~16Kts. Dry air is to the north and northwest of the system does not appear to be infiltrating the central area of what isolated convection there is. However, the system still remains in a less than favorable area of somewhat stable air – with no upper level wind support. As the system approaches the far eastern CARIB late this week, the environment should become somewhat more favorable for development.
Fig 3: Enhanced IR imagery over Africa earlier this morning highlights the very strong system in west-central Africa. This system had been moving W/SW for the last 36 hours – but has slowed its forward motion somewhat, and is expected to move on a West/Northwest (290°) during the next few days.
Fig 4: The above image over Africa includes satellite derived winds – and show a well established cyclonic flow around the major system of interest – just as it had for the last 2 days
Fig 5: The global models like the NAVY GEM above – and the GFS & CMC forecasts (not shown) all forecast the system to slowly intensify next week, with the GFS then carrying the system into the SE U.S. coast as a cyclone. Clearly, this system needs close monitoring.
May 19, 2014: Every ten days, the NASA/French Space Agency Jason-2 satellite maps all the world’s oceans, monitoring changes in sea surface height, a measure of heat in the upper layers of the water. Because our planet is more than 70% ocean, this information is crucial to global forecasts of weather and climate.
Lately, Jason-2 has seen something brewing in the Pacific—and it looks a lot like 1997.
“A pattern of sea surface heights and temperatures has formed that reminds me of the way the Pacific looked in the spring of 1997,” says Bill Patzert, a climatologist at NASA’s Jet Propulsion Laboratory. “That turned out to be the precursor of a big El Niño.”
A new ScienceCast video examines the evidence that an El Niño is developing in the Pacific. Play it
“We can’t yet say for sure that an El Niño will develop in 2014, or how big it might be,” cautions Mike McPhaden of NOAA’s Pacific Environmental Research Laboratories in Seattle, “but the Jason-2 data support the El Niño Watch issued last month by NOAA.”
What Jason-2 has been seeing is a series of “Kelvin waves”—massive ripples in sea level that travel across the Pacific from Australia to South America. Forecasters are paying close attention because these waves could be a herald of El Niño.
The two phenomena, Kelvin waves and El Niño, are linked by wind. Pacific trade winds blow from east to west, pushing sun-warmed surface waters toward Indonesia. As a result, the sea level near Indonesia is normally 45 cm higher than it is near Ecuador. Researchers call that area the “warm pool”—it is the largest reservoir of warm water on our planet.
Sometimes, however, trade winds falter for a few days or weeks, and some of that excess sea level ripples back toward the Americas. “That’s a Kelvin wave,” says McPhaden. “It’s not unusual to see a couple every winter.”
El Niño happens when trade winds falter not just for days, but for many months. Then Kelvin waves cross the Pacific like a caravan, raising sea level and leaving warmer equatorial waters in their wake.
On May 8th, the National Centers for Environmental Prediction forecasted a 65% chance of El Niño developing during the summer of 2014. More
“The El Niño of 1997/98 was a textbook example,” recalls Patzert. “At that time we were getting data from TOPEX/Poseidon, a predecessor of Jason-2. Sea surface maps showed a whitish bump, indicating a sea level some 10 centimeters higher than usual, moving along the equator from Australia to South America.”
“The same pattern is repeating in 2014,” says McPhaden. “A series of Kelvin waves generated by localized west wind bursts in the western Pacific that began in mid-January 2014 are headed east. Excitement is building as a third weakening of the Pacific trade winds happened in mid-April.”
Ocean and atmospheric scientists at NOAA and NASA are carefully monitoring the Pacific trade winds. The tipping point for declaring a significant El Niño will be an even longer lasting, larger collapse in Pacific trade winds, possibly signaling a shift in weather all around our planet.
“It will become much clearer over the next two to three months whether these recent developments are the forerunner of a major El Niño—or any El Niño at all,” says McPhaden.
Record May heat sent temperatures soaring above 100° in much of Southern California on Wednesday, and fierce Santa Ana winds fanned fires that scorched at least 9,000 acres in San Diego County, forcing thousands to evacuate. For the second consecutive day, the Los Angeles Airport set a record for the hottest May temperature since record keeping began in 1944. Wednesday’s 96° beat the record set on Tuesday of 93°. Other all-time May record heat was recorded at Camarillo (102°) and Oxnard (102°) on Wednesday. In Downtown Los Angeles, the mercury hit 99° on Wednesday, falling short of the all-time May record is 103° set on May 25, 1896. More record heat is forecast on Thursday, and hot offshore Santa Ana winds will bring extreme fire danger.
Figure 1. A firenado in Fallbrook, California at old Highway 395 and Interstate 15 on May 14, 2014. Image credit: Jena Rents via Twitter.
Figure 2. True-color MODIS satellite image of fires burning in Southern California and Northern Mexico on Wednesday afternoon, May 14, 2014. Image credit: NASA.
100% of California in severe to exceptional drought
Today’s U.S. Drought Monitor report showed grim news for California: 100% of the state is now in severe or higher drought, up from 96% the previous week. Though just 25% of California is classified as being in the highest level of drought, “Exceptional”, Erin McCarthy at the Wall Street Journal estimates that farms comprising 53% of California’s $44.7 billion market value lie in the Exceptional drought area. Averaged state-wide, the Palmer Drought Severity Index during April 2014 was the second worst on record, behind 1977. For the 12-month period ending in April, drought conditions in California for 2013 – 2014 were also the second most severe on record, slightly below the 2008 – 2009 drought. To break the drought, most of the state needs 9 – 15″ or precipitation to fall in one month. This amounts to more than a half-year’s worth of precipitation for most of the state.
Figure 3. The May 13, 2014 U.S. Drought Monitor showed 100% of California in severe or higher drought, with 25% of the state in the highest level of drought, “Exceptional.” Image credit: U.S. Drought Monitor.
California’s rainy season is over
The California October through April rainy season is now over. Between October 2013 and April 2014, the state received 10.44″ of precipitation, which is just 51% of average for the period, and the third lowest such total on record. Going back to 1895, the record low mark was set in 1976 – 1977, when the state got just 34% of its average rainy season precipitation. California typically receives less than 10% of its annual precipitation between May and September, and the coming hot and dry summer in combination with a severely depleted Sierra snowpack will cause a severe fire season and significant agricultural damages. The fifth and final snow survey of the season on May 1 found that the statewide snowpack’s water content–which normally provides about a third of the water for California’s farms and cities–was only 18% of average for the date. Already, the 2014 drought has cost the state at least $3.6 billion in agricultural damages, the California Farm Water Coalition estimates. CAL FIRE recently announced it had hired 125 additional firefighters to help address the increased fire threat due to drought conditions.
Tornado Alley To Be Active This Season With A Number Of Outbreaks
(TheWeatherSpace.com) – Recent trends suggest that the Central United States will be very active this season, whereas some seasons it is not. Numerous tornado outbreak events are likely.
As the upper jet stream starts to react to the closing season, troughs will dig further into California, thus the surface lows should form in Colorado and Kansas, bringing with it the perfect setup for violent tornado outbreaks. This is the seventh year of prediction made here at TheWeatherSpace.com about the tornado season. All predictions have been accurate, including the tornado drought in the plains a couple years back. This year will not feature a death ridge.
A death ridge is when a ridge of high pressure sets up over the Western United States, owning to a northwest flow into the region with no upper divergence or colder air aloft to push supercells off. This has happened a couple times in the seven year prediction period done on this site.
This year, however, is not a death ridge, but one where a trough should set-up end April into May across the Western United States. Impulses riding that into the Great Plains will bring the perfect ingredients for tornadoes … and since the jet may be in perfect orientation for these events, outbreaks are likely …
PEEP-O-NAUTS TAKE RISKY TRIP TO THE EDGE OF SPACE: On April 20th, the students of Earth to Sky Calculus launched a pair of suborbital helium balloons to the stratosphere. One payload carried a radiation sensor to measure the effects of the Easter geomagnetic storm on Earth’s upper atmosphere. The other payload carried a colony of halobacteria in an experiment to find out if the extremophiles could live at the edge of space. In honor of the holiday, the students launched some peeps as halobacteria companions. As this movie shows, it’s risky being a peep-o-naut:
The near-miss only 2000 ft. above the launch site almost brought an explosive end to the mission. Fortunately, the two balloons carried on to the stratosphere, gathering data on the solar storm in progress during the flight. Here is what peeps look like at the edge of space. Later, the peeps and halobacteria parachuted to Earth, landing in a tree in the Inyo Mountains of central California.
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.
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, www.nature.com/naturegeoscience.
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.
Links 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.”
