Thousands of dead fish Common carp (Cyprinus carpio). Public domain image from USFWS National Image Library. Created by Duane Rave
Thousands of Fish Die in Midwest Heat
As the Midwestern United States suffers from the worst drought combined with searing temperatures in 50 years, thousands of dead fish are turning up in lakes and rivers as water temperatures rise to almost 100 degrees, reports ABC News.
“It’s something I’ve never seen in my career, and I’ve been here for more than 17 years,” said Mark Flammang, a fisheries biologist with the Iowa Department of Natural Resources. “I think what we’re mainly dealing with here are the extremely low flows and this unparalleled heat.”
One of the worst cases of fish killed occured in Iowa when water temperatures reached 97 degrees, hot enough to kill more than 40,000 shovelnose sturgeon.
State officials commented that they have never seen such a massive die off of sea creatures in the last 20 years.
The massive die-off has caused a loss of $10 million to the state since the sturgeon are a prime source of caviar produced from their eggs.
Thousands of bass and catfish have likewise turned up dead in rivers in Illinois, with several endangered species threatened with extinction, including the greater redhorse fish in Illinois and the pallid sturgeon in Nebraska.
Flammang said since July, more than 3,000 existing heat records have been broken throughout the Midwest and forecasters can’t predict when the devastating heat and drought will end.
“Those fish have been in these rivers for thousands of thousands of years, and they’re accustomed to all sorts of weather conditions,” he said. “But sometimes, you have conditions occur that are outside their realm of tolerance.”
The following facts compiled by the AP give a good picture of just how bad things are:
• Iowa DNR officials said the sturgeon found dead in the Des Moines River were worth nearly $10 million, a high value based in part on their highly sought eggs, which are used for caviar.
• The federal U.S. Drought Monitor shows nearly two-thirds of the lower 48 states are experiencing some form of drought.
• The Department of Agriculture has declared more than half of the nation’s counties — nearly 1,600 in 32 states — as natural disaster areas.
• More than 3,000 heat records were broken over the last month.
Recap of record-breaking heat this past July in the U.S. Possible new heat record for Asia observed
Although the final ranking of this past July will not be released by the NCDC until around August 7th, it would appear that the month will almost certainly rank in the top five warmest July’s on record since official records began in 1895 (and perhaps even in the top three). Here is a summary of some of the more notable records set so far this summer. In addition, I have included a brief message concerning a potential new heat record for the continent of Asia.
Although this map is specifically for July 5th, it represents the overall pattern that most of the country has been stuck with for almost the entire month of July 2012.
Warmest Single Month on Record (any month)
Preliminary data from the NCDC reports that 4,313 record daily highs, 293 monthly record highs, and 171 all-time record highs were observed this past July (among the approximately 5,500 various official weather sites across the nation). Many of these sites, however, have limited periods of record that do not extend back to the 1930s when the country’s greatest heat waves occurred.
The WU extremes U.S. database follows 298 significant sites in the country, all of which have long periods of record (almost all back to the 19th century) and represent a mosaic of evenly spaced geographic locations representing all the climate zones in the country. About 90% of the country’s population resides within a 50-mile radius of one of these sites. From this list the following cities recorded their single-warmest month on record:
The following cities from the WU extremes database have broken or tied their all-time absolute maximum temperatures on record (including this past June):
Comparing this July to July of 2011
Perhaps what is truly astonishing is that this July (2012) piggybacks upon the equally torrid summer (and July) of 2011. Although, back-to-back record-breaking hot summers are not unheard of (summers in the 1930s and 1950s come to mind) it is nevertheless disconcerting.
Here is a comparison of extremes reached in July 2012 versus July 2011. Also, to put this in context, is a comparison to July of 1936, still almost certainly the hottest July (and single month) in U.S. records. Again this list includes only the 298 cities in the WU database:
This table shows the number of cities (out of 298 in all) that recorded their respective single-warmest month on record and absolute maximum temperature on record for the June-July month timeframes in 2012, 2011, and 1936.
Other major cities came VERY close to breaking their all-time warmest single month on record including Washington, D.C. (National Airport) with a July average of 84.0° just shy of the record 84.5° set last July (2011). The Dulles Airport location was also close with 80.6° vs. 81.0° in July 2011. Raleigh, North Carolina averaged 83.5°, shy of their record 84.1° set in August 2007. Chicago, Illinois official site at O’Hare Airport registered an average of 81.1° just short of the 81.3° record set in July 1995. However, the Chicago Midway Airport location, which is more representative of the city itself and also has a much longer period of record (POR) than O’Hare, smashed its all-time warmest month record with an average of 82.6° versus 81.3° in July 1955. Louisville, Kentucky experienced its warmest ever July with an average of 84.5°, but fell short of its single-hottest-month record of 85.0° set in August 2007. Madison, Wisconsin (home of my alma matter!) has just endured its 2nd hottest month on record with a 79.4° average, just short of the record 79.8° set way back in July 1901.
Of course, this is just a short list of the many amazing ‘heat feats’ this past July. I should also mention a couple of the many endurance records that have been set:
Fort Wayne, Indiana: 22 consecutive days above 90° ending on July 18 (old record was 14).
St. Louis, Missouri: 11 days above 105° (old record was 10 in 1934). Also, St. Louis tied its warmest night on record with a low of 86° on July 25th (also occurred on July 24, 1901).
New Asian Heat Record Set?
On a similar topic but different continent, I have late word in from temperature detective Maximiliano Herrera that on July 31st a temperature of 53.6°C (128.5°F) was measured at Sulaibya (Sulaibiya), Kuwait. This location is on the outskirts of Kuwait city and is a water treatment facility.
A Google map image of the location in Kuwait of Sulaibya. Google Earth image.
Although the Kuwaiti meteorological office must make a final determination towards the records validity, a local expert, Dr. Juergen Herrmann (Team Leader Meteorology Specialists, Stanley Consultants, Int’l based in Kuwait) has the following comments in response to a request from Max for additional details:
“We are aware of the new record temperatures. There is no reason why these should not be considered records. Everything is technically OK at the station. You may have detected that the same day we had quiet an amount of other stations in the “vicinity” also have high to record temperatures.
The microclimate at this agro-station is surrounded by high sand dunes and thus has very low wind speeds at 2m height [which] results in a local heat island. Therefore I would not consider this temperature representative for an area bigger than 0.5×0.5km. The next station to Sulaibiya which gives a proper picture for the surrounding area is Jahra – 40586 – and had maximum temperature at the same day of 51.8 deg C. To my best guess this verifies both stations are working properly. Especially as a number of other stations also had really high temperatures that day due to generally low wind speeds with nearly no dust reducing the incoming solar radiation.”
If verified, this would surpass the 53.5°C (128.3°F) measured at Moen Jo-Daro, Pakistan on May 26, 2010. The reading of 54°C (129.2°F) from Tirat Tsvi, Israel on June 22, 1942 remains under suspicion. The Israeli Met. Office pursued an investigation of the record this past year (prompted by an enquiry from the WMO and myself) and concluded it was valid. However, they have refused to make public the details leading to their conclusions, so until they do so the record remains suspect.
KUDOS: Maximiliano Herrera for uncovering yet another possible world record temperature.
The Southwest may be stuck with more scenes like this dry lake bed.
The United States is parched, with more than half of the land area in the lower 48 states experiencing moderate to extreme drought, according to a report released today (July 5).
Just under 56 percent of the contiguous United States is in drought conditions, the most extensive area in the 12-year history of the U.S. Drought Monitor. The previous drought records occurred on Aug. 26, 2003, when 54.79 percent of the lower 48 were in drought and on Sept 10, 2002, when drought extended across 54.63 percent of this area.
When including the entire nation, the monitor found 46.84 percent of the land area meets criteria for various stages of drought, up from 42.8 percent last week. Previous records: 45.87 percent in drought on Aug. 26, 2003, and 45.64 percent on Sept. 10, 2002.
The recent heat and dryness is catching up with us on a national scale,” Michael Hayes, director of the National Drought Mitigation Center at the University of Nebraska-Lincoln, said in a statement. “Now, we have a larger section of the country in these lesser categories of drought than we’ve previously experienced” in the past 12 years.
The monitor uses a ranking system that goes from D0 (abnormal dryness) to D1 (moderate drought), D2 (severe drought), D3 (extreme drought) and D4 (exceptional drought).
At the lower end of the scale, moderate drought involves some damage to crops and pastures, and low water levels in streams, reservoirs or wells. Areas in exceptional drought would experience widespread crop and pasture losses and water shortages that lead to water emergencies. Currently, 8.64 percent of the country would meet criteria for either extreme or exceptional drought.
“During 2002 and 2003, there were several very significant droughts taking place that had a much greater areal coverage of the more severe and extreme drought categories,” Hayes said. “Right now we are seeing pockets of more severe drought, but it is spread out over different parts of the country.
“It’s early in the season, though. The potential development is something we will be watching,” he added.
Further into the past, the United States has experienced some really serious droughts, including one in the 1930s, the Dust Bowl drought, and another in the 1950s, each of which lasted five to seven years and covered large swaths of the continental United States. Droughts are one of the most costly weather-related events in terms of economics and loss of life, according to the National Oceanic and Atmospheric Administration (NOAA). Between 1980 and today, 16 drought events cost $210 billion, according to a recent report.
While no single event like this year’s extensive drought can be said to be the result of global warming, scientists say more extreme weather should be expected as the planet warms, according to a report compiled by the Intergovernmental Panel on Climate Change (IPCC) in 2011. That year, there were 12 $1-billion disasters.
In particular, the report authors predicted that with climate change there would be an increase in certain types of extreme weather, including daily high temperatures, heat waves, heavy precipitation and droughts, in some places.
The U.S. Drought Monitor is a joint endeavor by the National Drought Mitigation Center, NOAA, the U.S. Department of Agriculture and drought observers across the country.
Intense heat continues to bake a large portion of the U.S. this Tuesday, with portions of 17 states under heat advisories for dangerously high temperatures. The heat is particularly dangerous for the 1.4 million people still without power and air conditioning due to Friday’s incredible derecho event, which is now being blamed for 23 deaths. The ongoing heat wave is one of the most intense and widespread in U.S. history, according to wunderground’s weather historian, Christopher C. Burt. In his Sunday post, The Amazing June Heat Wave of 2012 Part 2: The Midwest and Southeast June 28-30, Mr. Burt documents that eighteen of the 298 locations (6%) that he follows closely because of their long period of record and representation of U.S. climate broke or tied their all-time heat records during the past week, and that “this is especially extraordinary since they have occurred in June rather than July or August when 95% of the previous all-time heat records have been set for this part of the country.” The only year with more all-time heat records than 2012 is 1936, when 61 cities of the 298 locations (20%) set all-time heat records. The summer of 1936 was the hottest summer in U.S. history, and July 1936 was the hottest month in U.S. history.
According to wunderground analysis of the National Climatic Data Center (NCDC) extremes database, during June 2012, 11% of the country’s 777 weather stations with a period of record of a century or more broke or tied all-time heat records for the month of June. Only 1936 (13% of June records broken or tied) and 1988 (12.5%) had a greater number of all-time monthly June records. I expect when NCDC releases their analysis of the June 2012 weather next week, they will rank the month as one of the top five hottest Junes in U.S. history.
Figure 1. Across the entire Continental U.S., 72% of the land area was classified as being in dry or drought conditions as of June 26, 2012. Conditions are not expected to improve much over the summer: the NOAA Climate Prediction Center’s latest drought outlook shows much of the U.S. in persistent drought conditions, with very few areas improving. The rains brought by Tropical Storm Debby did help out Florida and Georgia, however. Image credit: NOAA Environmental Visualization Laboratory.
The forecast: hot and dry
July is traditionally the hottest month of the year, and July 2012 is likely to set more all-time heat records. The latest predictions from the GFS and ECMWF models show that a ridge of high pressure and dry conditions will dominate the weather over about 80 – 90% of the country during the next two weeks, except for the Pacific Northwest and New England. This will bring wicked hot conditions to most of the nation, but no all-time heat records are likely to fall. However, around July 11, a sharp ridge of high pressure is expected to build in over the Western U.S., bringing the potential for crazy-hot conditions capable of toppling all-time heat records in many western states.
The intense heat and lack of rain, combined with soils that dried out early in the year due to lack of snowfall, have led to widespread areas of moderate to extreme drought over much of the nation’s grain growing regions, from Kansas to Indiana. The USDA is reporting steadily deteriorating crop conditions for corn and soybeans, and it is likely that a multi-billion dollar drought disaster is underway in the Midwest.
The wunderground Extremes page has an interactive map that allows one to look at the records for the 298 U.S. cities that Mr. Burt tracks. Click on the “Wunderground U.S. Records” button to see them.
Quiet in the Atlantic
There are no threat areas to discuss in the Atlantic, and none of the reliable computer models are developing a tropical cyclone over the next seven days.
Have a great 4th of July holiday, everyone, and I’ll be back Thursday with a new post.
Tropical storm warnings continue to fly from Alabama eastward to Suwannee, Florida, as Tropical Storm Debby sits motionless over the Gulf of Mexico. On Sunday, Debby spawned a multitude of severe thunderstorms over much of Florida, which brought torrential rains, damaging winds, and numerous tornadoes. NOAA’s Storm Prediction Center logged 20 preliminary tornado reports on Sunday, and a tornado in Venus, Florida killed one person. Venus is in Central Florida, between Port St. Lucie and Sarasota. Another person is missing in Alabama, swept away by rough surf. The heaviest rains of Debby affected the Tampa Bay region, where over ten inches were reported at several locations. The Tampa Bay airport picked up 7.11 inches on Sunday. It’s a good thing this isn’t the week of the Republican National Convention, which is scheduled for late August in Tampa! Minor to moderate flooding is occurring at three rivers near Tampa, and flooding has been limited by the fact the region is under moderate to severe drought.
Figure 1. Radar-estimated rainfall from Tropical Storm Debby has totaled over 6 inches (orange colors) along a swath from Tampa to Ocala.
Winds from Debby have fallen considerably since Sunday, thanks to a slug of dry air that wrapped into Debby’s core, disrupting the storm. Our Wundermap for the surrounding ocean areas shows that winds at almost all buoys and coastal stations along the Gulf Coast were below 30 mph at 8am EDT. The exception was a Personal Weather Station at Bald Point, near Apalachiacola, Florida, which reported sustained winds of 32 mph. An Air Force hurricane hunter aircraft flying through Debby has measured top surface winds of 43 mph as of 9 am EDT. Visible satellite loops show Debby has virtually no heavy thunderstorms near its center of circulation, which will severely limit its potential for intensification today. The heavy thunderstorms of Debby are mostly on the east and north sides. Upper-level winds out of the west creating a moderate 10 – 20 knots of wind shear that continues to drive dry air into Debby’s core. This dry air can be seen on Water vapor satellite loops. Ocean temperatures are about 27.5°C (81°F) in the Northern Gulf of Mexico, which is about 1°F above average, but these waters do not extend to great depth, which will limit how strong Debby can get.
Figure 2. True-color visible Aqua satellite image of Debby taken at 3 pm EDT Sunday June 24, 2012. At the time, Debby had top winds of 60 mph. Image credit: NASA.
Forecast for Debby
Debby’s slow motion will make rainfall the primary threat from the storm, though tornadoes will continue to be a threat over the next few days. NOAA’s Storm Prediction Center has placed most of Florida in its “Slight Risk” area for severe weather today. The slow motion of Debby will inhibit intensification of the storm by stirring up cooler waters from the depths to the surface. Debby’s close proximity to land places a portion of its circulation over land, which will also tend to slow down intensification. Wind shear is expected to remain in the moderate range through Wednesday. I expect Debby will begin to build heavy thunderstorms near its core today and Tuesday, with the winds increasing again to 60 mph by Wednesday morning. The latest SHIPS model forecast gives Debby just a 4% chance of undergoing rapid intensification–a 30 mph increase of winds in 24 hours. The 8 am EDT NHC wind probability forecast is giving Debby a 19% chance of becoming a hurricane by early Wednesday morning. Steering currents for Debby are very weak, a the storm should hang out in its current location for several more days. The models continue to have a large spread in where they thing Debby might eventual make landfall, and the official NHC forecast may have large errors for its positions at the 3 – 5 day range.
Colorado’s 114°: hottest temperature in state history
The remarkable heat wave that affected Colorado on Saturday and Sunday has tied the all-time heat record for the state. According to wunderground’s weather historian Christopher C. Burt, Saturday’s 114° reading in Las Animas tied for the hottest temperature ever measured in the state of Colorado. Two other 114° readings have occurred in Colorado history: in Las Animas on July 1, 1933, and in Sedgwick on July 11, 1954.
Colorado Springs tied its all-time record for warmest temperature ever measured on both Saturday and Sunday, with readings of 100°. The city has hit 100° four other times, most recently on July 24, 2003. The record heat in Colorado Springs exacerbated a wildfire that grew to more than 3 square miles on Sunday, driving 11,000 residents (2% of the city’s population) out of their homes.
In Fort Collins, the mercury hit 102° on Sunday, just 1° below the city’s all-time hottest temperature of 103° set on Jul 21, 2005. The heat did no favors for firefighters struggling to the contain the massive 81,000 acre High Park fire fifteen miles northwest of Fort Collins. The fire is the second largest and most destructive wildfire in Colorado’s history, and is 45% contained.
La Junta, CO hit 110° on Sunday, tying its all-time hottest temperature record, set on June 28, 1990.
The heat wave extended into neighboring Kansas, where Hill City hit 114°, tying its all-time warmest June temperature. Tribune, Kansas hit 109°, tying its all-time hottest temperature. Goodland, Kansas hit 109°, its hottest June temperature on record.
Two more days of exceptional heat are predicted for Colorado and Kansas, with the forecast for Denver calling for a high of 101 – 104° on Monday. The city hit 102° on Sunday, just 3° below the hottest temperature ever recorded in Denver, the 105° readings on July 20, 2005 and August 8, 1878.
Last month, the global average temperature climbed to the second highest for May on record since 1880, according to U.S. National Oceanographic and Atmospheric Administration (NOAA) records.
Much of the world, including nearly all of Europe, Asia, northern Africa, most of North America and southern Greenland experienced above average May temperatures. In fact, last month wrapped up the warmest spring on record for the continental U.S., NOAA records show.
The global May record included the combined global land and ocean average surface temperatures for the month, which 1.19 degrees Fahrenheit (0.66 degrees Celsius) above the 20th-century average of 58.5 F (14.8 C). This record was beat only in 2010, when the global average was 1.24 F (0.69 C) above the 20th-century average.
The Northern Hemisphere saw its warmest May on record — 1.53 F, or 0.85 C above average — while the Southern Hemisphere’s May ranked ninth warmest among all Mays on record, at 0.85 F (0.47 C) above average.
Of course, it wasn’t unusually warm everywhere. Australia, Alaska and parts of the western U.S.-Canadian border were notably cooler than average.
Snow cover on the Northern Hemisphere was significantly below average in May, according to NOAA records.
Globally, this spring ranked as the fourth warmest. Meanwhile, May brought a slew of temperature records to the continental U.S. after an unusually warm spring and mild winter.
Because of natural fluctuations in weather, climate scientists are loath to connect events that occur over a short-time frame, from a strong storm to an unusual warm spring, to climate change. However, the warming effect of humans’ greenhouse gas emissions forms a backdrop for the weather the world is experiencing and shows up as a longer-term trend. It is not a coincidence that the first decade of this century was the warmest on record, according to NOAA’s State of Climate in 2010 report.
The most incredible spring heat wave in U.S. and Canadian recorded history is finally drawing to a close today, after a ten-day stretch of unprecedented record-smashing intensity. Since record keeping began in the late 1800s, there have never been so many spring temperature records broken, and by such a large margin. Airports in fifteen different states have set all-time records for March warmth, which is truly extraordinary considering that the records were set in the middle of the month, instead of the end of the month. The 29.2°C (85°F) measured at Western Head, Nova Scotia yesterday was the third warmest temperature ever recorded in Canada in March, according to Environement Canada and weather records researcher Maximiliano Herrera (top two records: 31.1°C at Alberini Beaver Creek BC on March 29th 1926, and 29.4°C in 1921 at Wallaceburg.) Michigan’s all-time record for March warmth was toppled on Wednesday, when the mercury hit 90°F at Lapeer. The previous record, 89° at Lapeer in 1910, was matched at three stations yesterday–Ypsilanti, Dearborn, and Lapeer. The duration, areal size, and intensity of the Summer in March, 2012 heat wave are simply off-scale, and the event ranks as one of North America’s most extraordinary weather events in recorded history. Such a historic event is difficult to summarize, and in today’s post I will offer just a few of the most notable highlights.
Figure 1. Clear skies over the Eastern U.S. caused by a blocking ridge of high pressure on March 21, 2012, are apparent in this visible satellite image. The comma-shaped cloud pattern over the Central U.S. is associated with a “cut-off” low pressure system. This low is moving over the Eastern U.S. today through Saturday, and will bring an end to “Summer in March” over the U.S. and Canada. Image credit: NOAA’s Environmental Visualization Lab, and modified by Andrew Freedman of Climate Central.
Low temperatures beating previous high temperature records for the date
I’ve never seen a case where the low temperature for the date beat the previous record high. This happened on at least four occasions during “Summer in March, 2012”:
The low temperature at Marquette, Michigan hit 52° on March 21, which was 3° warmer than the previous record high for the date.
The low temperature for International Falls, Minnesota on March 20 bottomed out at 60°F, tying the previous record high for the date.
The low temperature in Rochester, Minnesota on March 18 was 62°F, which beat the previous record high for the date of 60°.
Breaking all-time April records for warmth in March
Not only did many locations in Canada set records for their all-time warmest March day during “Summer in March, 2012”, a number also broke their record for warmest April day:
St. John, New Brunswick hit 27.2°C (81°F) on March 21. Previous March record: 17.5°C on March 21, 1994. April record: 22.8°C.
Halifax, Nova Scotia hit 27.2°C (81°F) yesterday. Previous March record: 25.8° set the previous day. April record: 26.3°C, set on April 30, 2004.
Breaking daily temperature records by more than 30°F
It is exceptionally rare for a weather station with a 50+ year period of record to break a daily temperature record by more than 10°F. During “Summer in March, 2012”, beating daily records by 10° – 20°F was commonplace, and many records were smashed by over 20°. Two stations broke records by more than 30°F, which is truly surreal. Western Head, Nova Scotia hit 29.2°C (85°F), yesterday, breaking their previous record for the date (10.6°C in 1969) by 18.6°C (33°F.) Yesterday’s high temperature was 24°C (44°F) above average. Pellston, Michigan in the Northern Lower Peninsula–dubbed “Michigan’s Icebox”, since it frequently records the coldest temperatures in the state–hit 85° on March 21. This broke the previous record for the date (53° in 2007) by 32°, and was an absurd 48°F above average.
Breaking daily temperature records nine consecutive days or more
It is extremely rare for stations with a 50+ year period of record to break a daily high temperature record for seven or more days in a row. The longest such streak of consecutive high temperature records at International Falls, Minnesota, was a 5-day period March 3 – 7, 2000. The city has tied or broken their high temperature for the date ten consecutive days, as of yesterday. This streak will likely end today, as the high is predicted to be 60 – 65, and the record high for the date is 66. Chicago, Illinois has tied or broken their daily high temperature record the past nine days in a row. This ties the nine-day streak of record highs set on August 26 – September 3, 1953. Other cites that have set daily high temperature records the past nine days in a row include Fort Wayne and South Bend, Indiana. Numerous cities have broken high temperature records on seven consecutive days during “Summer in March, 2012”, including Gaylord, Pellston, and Traverse City in Michigan.
Figure 2. All-time high temperature records set in March 2012 for the U.S. The grey icons show locations where the March record was broken on multiple days. Image taken from wunderground’s new record extremes page, using data from NOAA’s National Climatic Data Center.
The big picture: the impacts of “Summer in March, 2012”
I’ve always said living in Michigan would be much more bearable if we could just get rid of March. March weather here is always horrible, with brutal cold, high winds, damaging ice storms, heavy snow, interminable cloudy stretches with no sun, all interspersed with a few teasing warm spells. Well, this year, I got my wish. This March, we started with twelve days of April weather, followed by ten days of June and July weather, with nine days of May weather predicted to round out the month. This has been a huge benefit to the economy–vastly reduced heating costs, no snow removal bills, and far fewer traffic accidents due to icy roads. However, there is major downside to the “Summer in March, 2012” heat wave. The growing season is now in full swing, five weeks early. A damaging freeze that will severely impact the fruit industry and other sensitive plants is very likely. Indeed, the forecast calls for lows in the upper 20s in the cherry-growing region of Michigan near Traverse City on Monday night. The exceptional March warmth has also melted all the snow in the northern U.S. and southern Canada, drying out the soils and setting the stage for a much warmer than average summer, and an increased chance of damaging drought conditions. The early loss of snowpack will also likely cause very low flow rates in the major rivers in late summer and early fall, reducing the amount of water needed for irrigation of crops. Low flows may also cause problems for navigation, limiting commercial barge traffic on Midwest rivers.
fr/Dr. Jeff Masters, an analysis of weather in July:
According to the National Climatic Data Center‘s Climate Extremes Index, July 2011 was the most extreme July on record (since 1910) with a value of 37%. The Climate Extremes Index is created by merging the various climate indicators (drought, flood, extreme heat, extreme cold, etc.) into an index that can be tracked over time. This month’s record CEI was due to extreme warm minimum temperatures across the country, wet northern Plains and Great Lakes, extreme warm maximum temperatures, and the severe drought across the South and Gulf Coast.
It was the fourth warmest July on record for the nation, and the fourth warmest month overall with an average temperature of 77°F. Extreme heat continued to bake the South, and Oklahoma and Texas both had their warmest months on record. Oklahoma’s statewide average temperature was a remarkable 88.9°F in July, which is the warmest monthly statewide average for any state in any month. Dallas, Texas hit or exceeded 100°F on 30 out of the 31 days in July. For the entire South climate region, which comprises Texas, Oklahoma, Kansas, Louisiana, Arkansas, and Mississippi, July 2011 was the warmest month on record for any of the climate regions.
As we noted in a previous blog, an unprecedented area of exceptional drought covered the United States in July, the largest area in the history of the U.S. Drought Monitor. 75% of Texas was in an exceptional drought, and the entire state of Oklahoma was in moderate to exceptional drought in July. The NCDC estimates that it would take 20 inches of rain to end the drought in one month in the worst hit areas of Oklahoma and Texas.
Dust storm rolls through Phoenix overnight, excessive heat continues
by Catherine Holland
Posted on August 3, 2011 at 6:26 AM
Updated today at 4:54 PM
PHOENIX – Mother Nature took another swipe at the Valley, delivering the fourth major dust storm of the monsoon early Wednesday morning, which was also one of the warmest mornings we’ve seen in some.
The storm slowly rolled across the Valley between 1 a.m. and 3 a.m., leaving dust hanging in the air hours later. Some early morning commuters thought the dusty haze was fog.
While many people might have heard the wind, they didn’t realize another dust storm had hit until they saw the layer of dust on their cars.
The National Weather Service issued a dust storm warning just before 1 a.m. The storm pushed up from the Tucson area through Pinal County and into Phoenix metro area, bringing high winds and lots of dust.
It was mostly over by the time “Good Morning! Arizona” went on the air at 4:30 a.m., but there still was some thunderstorm activity in Pima County, as well as some light shower in Pinal County. That storm activity was dying down as the sun came up.
Because it happened in the middle of the night, it’s difficult to compare the severity of Wednesday morning’s dust storm with the previous three storms.