Thursday, March 22, 2018

National Drought Mitigation Center

May 2015 Drought and Impact Summary

Historic rainfall erases nearly all drought in southern Plains, Upper Midwest improves, Northeast dries out, West still parched

by Brian Fuchs, NDMC climatologist


Historic rainfall in May in the southern Plains led to significant reductions in drought. The Upper Midwest also saw substantial improvement. But drought developed over portions of New England. For the 48 contiguous states, drought conditions improved from 37.41 percent in drought on April 28 to 24.57 percent on June 2. During the same period, severe drought improved from 20.03 to 14.19 percent, extreme drought improved from 8.10 to 7.09 percent and exceptional drought improved from 3.41 to 3.13 percent. At the end of May, 70.7 million people were in drought-affected areas, compared to 73.7 million at the beginning of the month.


The drought outlook for June has drought persisting over much of the western United States with further development along the coastal regions of the Pacific Northwest. Continued improvements are expected in the remaining drought areas of the Plains and Midwest. The drought in New England will persist, with the potential for some improvements. Drought will expand in Puerto Rico.


Temperatures were quite different in May compared to most of the rest of this year. Warmer-than-normal temperatures were observed east of the Mississippi River Valley, while cooler-than-normal temperatures were present over much of the West. New England was 6-8 degrees Fahrenheit warmer than normal, while the Southwest was 4-6 degrees cooler than normal. The Pacific Northwest was also 4-6 degrees warmer than normal.


A good portion of the central U.S. had above-normal precipitation in May, with the East and West coasts both drier than normal. In the Central and Southern Plains, almost all areas were 4-8 inches wetter than normal, with portions of Oklahoma and Texas receiving 8-12 inches, which led to extensive flooding. Areas along the coasts were generally as much as 4 inches drier than normal for the month.

Movers & Shakers for May 2015

Percent area
April 28, 2015
Percent area
June 2, 2015
Status Percentage point change

Biggest increases in drought
66.60 69.61 extreme 3.01
Connecticut 0.00 44.32 moderate 44.32
Florida 5.14 8.71 moderate 3.57
Georgia 0.00 8.71 moderate 8.71
Idaho 48.07 65.15 moderate 17.08
21.83 26.19 severe 4.36
Maine 0.00
7.22 moderate 7.22
Massachusetts 0.00
71.91 moderate 71.91
New Hampshire
50.40 moderate 50.40
New Jersey
0.00 5.84 moderate 5.84
New York
0.00 15.74 moderate 15.74
Oregon 63.17 68.48 severe 5.31
Puerto Rico
0.00 29.15 moderate 29.15
Rhode Island
0.00 31.43 moderate 31.43
Vermont 0.00 18.32 moderate 18.32
Washington 15.20 23.76 severe 8.56
Biggest improvements in drought

50.86 16.73 moderate 34.13
35.92 0.00 severe 35.92
23.33 20.12 moderate 3.21
Kansas 67.89 4.68 moderate 63.21
26.18 0.00 severe
3.17 0.00 extreme 3.17


92.45 12.06 moderate 80.39
31.88 0.00 severe 31.88
Nebraska 28.15 5.18 moderate 22.97
New Mexico
55.64 36.22 moderate 19.42
17.97 11.95 severe 6.02
North Dakota
27.42 0.00 moderate 27.42
Oklahoma 59.29 0.00 moderate 59.29
47.51 0.00 severe 47.51
24.34 0.00 extreme 24.34
4.13 0.00 exceptional 4.13
South Dakota
77.10 6.94 moderate 70.16
15.98 0.00 severe 15.98
Texas 30.71 0.64 moderate 30.07
15.83 0.00 severe
5.57 0.00 extreme 5.57
Utah 99.19 90.63 moderate 8.56
45.74 34.48 severe 11.26
Wisconsin 48.08 2.95 moderate 45.13
Wyoming 14.31
0.54 moderate 13.77

Regional Overviews


May temperatures were well above normal in the Northeast, with almost the entire region 6-8 degrees warmer than usual. Precipitation was spotty, with the greatest amounts recorded in small areas of northern Maine and New York. The coastal regions were 2-4 inches drier than normal. Moderate drought crept into New England, with 12.89 percent of the region in drought at the end of the month compared to none at the beginning of the month.  


Temperatures were mostly 2-4 degrees warmer than normal across the Southeast in May.  The greatest departures from normal were from the Carolinas into the Mid-Atlantic states. Precipitation was generally below normal by 2-4 inches.  However, the gulf coast of Florida, western Georgia, and southern Alabama were generally 2-4 inches wetter than normal. Drought increased slightly during May, with 3.50 percent of the region in drought on June 2, compared to 1.01 percent at the end of April. A small patch of severe drought emerged in far south Florida on the June 2 Drought Monitor.


Much of the Midwest was warmer than normal for May, by as much as 4-6 degrees over the eastern extent of the region. But Minnesota and eastern Iowa and Missouri were 2-4 degrees cooler than normal. The warmer areas were also up to 4 inches drier than normal, while the rest of the region was up to 4 inches wetter than normal, and even more in western Minnesota. Drought in the Midwest improved in May, with only 2.37 percent of the region in drought at the end of the month compared to 21.28 percent at the end of April. There was no severe drought remaining in the Midwest, and the only remaining drought areas were in Minnesota and Wisconsin.

High Plains

Temperatures on the High Plains were generally 4-5 degrees cooler than normal for May. Most of the region was wetter than normal by up to 6 inches. Portions of southern Kansas and western Nebraska were 6-12 inches above normal. Central Nebraska and western North Dakota were the anomalies, where precipitation was below normal. The area of the region in drought improved from 43.87 to 6.12 percent. Rains eliminated severe and extreme drought from Kansas in May.


The entire region recorded above-normal precipitation, with record-breaking amounts over portions of Texas and Oklahoma which led to flooding over areas that had been in drought for several years. Many areas had their wettest May on record as well as their wettest month ever on record. Some areas of Oklahoma and north Texas were 16-20 inches above normal for the month, rapidly improving conditions in the region after four or more years of drought. Temperatures were mixed in the southern region, with the wettest areas also the coolest. Departures from normal ranged from 4-5 degrees cooler than usual in the panhandles of Oklahoma and Texas to 1-2 degrees warmer than usual in Arkansas and Louisiana. Drought at the end of May covered only 0.32 percent of the region compared to 23.41 percent at the end of April. Severe, extreme, and moderate drought are absent from the southern region for the first time since 2010.


Cooler-than-normal temperatures extended into the West, with most of the region 2-4 degrees cooler than normal for May, except in the Northwest, where temperatures were 4-6 degrees warmer than normal. Coastal regions were dry, with most areas 2-4 inches below normal for May. But much of the rest of the region was 2-4 inches wetter than normal. Drought improved over the region in May, with 56.98 percent of the region in drought on June 2, compared to 62.12 percent at the end of April. Severe drought improved from 39.33 to 35.92 percent of the region, extreme drought increased from 17.64 to 17.99 percent of the region and exceptional drought went from 7.95 to 7.94 percent of the region. 

Ongoing drought in West affects farmers, rural and urban water users, and wildlife

Of the 144 impacts in the Drought Impact Reporter for May 2015, a quarter concerned government response to drought and 30% related to water supply.
California had the most impacts reported in May 2015, followed by Oregon, Nevada, Washington, Texas, Montana, North Carolina and Utah.

Texas' cumulative reservoir storage climbed steeply in April and May and is now over 80 percent, approaching the historic median. Texas charts are from Water Data for Texas.

As of early June, Texas' eastern reservoirs were full or nearly full, contrasting with those in the Panhandle and central portion of the state.
The table above shows that recent reservoir levels in Texas were considerably higher in early June than they were a few months earlier.
Illustrating this year's snow drought in the West, the chart above from California's Department of Water Resources shows that as of June 1, 2015, snowpack was 0 percent of normal for the date for all three of the state's snowpack monitoring regions.
As of May 31, all of the major reservoirs depicted on the chart above from California's Department of Water Resources were below historical averages, and all but three were less than half full.

by Denise Gutzmer, Drought Impact Specialist

Unusual May rainfall drastically eased drought in parts of the southern Great Plains that have been parched for five years. Parts of Texas and Oklahoma that were parched in April were inundated with record rainfall and saw intense flooding. Parts of California’s Sierra Nevada, too, saw abundant rain in May, but it was not enough to ease drought conditions. The moisture did, however, improve pasture and boost the growth of fine fuels that could pose a fire danger later in the year. Reservoirs did not benefit significantly from the rain, leaving water shortages and restrictions the top concerns for California. For the month so far, 74 impacts for California have been recorded in the Drought Impact Reporter, with 15 for Oregon, 14 for Nevada and 11 for Washington.
“Much of Sierra sees big rainfall, snow totals in May,” by Phillip Reese and Dale Kasler, The Sacramento Bee (Calif.), May 29, 2015


Stepping up water conservation efforts

As of June 1, California had zero percent of its average amount of snow, the lowest measurement ever recorded at that time of year, underscoring the urgent need for conservation amid the state’s fourth year of drought. The State Water Resources Control Board imposed water conservation goals as high as 36 percent for some water agencies and cities, and some communities faced water budgets and rationing to comply with the requirement for water conservation. The public stepped up their water conservation efforts and used 13.5 percent less water in April compared with April 2013, the benchmark year, an improvement over water savings of 3 percent in February and 4 percent in March.
“California Snow Pack Hits Historic Low, 0%,” by Jeffrey Hess, Valley Public Radio (Fresno, Calif.), June 1, 2015
“California Water Use Fell 13.5 Percent In April Amid Drought,”
by Associated Press, CBS Sacramento (Calif.), June 2, 2015

Senior water rights holders in Delta made deal with water authorities

The State Resources Water Control Board announced impending curtailment orders for senior water rights holders, comprised mainly of agricultural districts. Farmers with senior water rights in the Sacramento-San Joaquin Delta countered by offering to curb their water use by 25 percent in exchange for the reassurance that their remaining water would remain untouched by the SRWCB for the rest of the growing season.  Junior water rights holders were notified on May 1 that they must end water diversions.
“California farmers in line for more drought cutbacks,” by Dale Kasler and Phillip Reese, The Sacramento Bee (Calif.), May 11, 2015
California drought: State approves farmers’ offer of 25% voluntary water cuts ,” by Fenit Nirappil, Associated Press, The Fresno Bee (Calif.), May 22, 2015

About 1,900 dry wells as groundwater levels continue to drop

Groundwater levels continued their decline, with roughly 1,900 wells now dry, reported Mark Cowin, director of the state Department of Water Resources. Of the 4,500 or so monitored wells in the state, 40 percent have dropped more than 2 feet, more than 15 percent have fallen in excess of 10 feet, and some wells plummeted more than 25 feet in central California. "Significant to severe" drops in groundwater were also seen in the Central Coast and Southern California.
California water officials deliver sobering facts on depleted wells,” by Matt Stevens, Los Angeles Times, May 17, 2015

Fund established to respond to drinking water emergencies in California

With groundwater levels declining, the State Water Resources Control Board approved guidelines for funding to assist community water systems, nonprofit organizations, tribal governments and public agencies with drinking water emergencies. A fund of $19 million was designated to be used for bottled water and drought-related projects.
“New guidelines approved for emergency drought relief funding,” by Veronica Rocha, Los Angeles Times, May 19, 2015

Public favors mandatory water restrictions, holds dim view of future growth

The drastic reduction in available water changed people’s opinions on water conservation as evidenced by a new Field Poll. Sixty-five percent of Californians favored the mandatory water conservation of 25 percent issued by Gov. Brown. At the same time, many people thought it would be difficult to conserve more water and felt that farmers could find ways to cut back.

Field Poll results also showed that Californians held an increasingly pessimistic view of the future of their state. The water situation and the ramifications for the public, the state’s future growth and the overall economy were uppermost on people’s minds.
“Poll: Large majority of Californians support water restrictions amid drought,“ by David Siders, The Sacramento Bee (Calif.), May 18, 2015
Drought angst shrivels Californians' views of state,” by Christopher Cadelago, The Sacramento Bee (Calif.), May 26, 2015

People more cognizant of own, others’ water use

As awareness of the drought and limited water resources continued to come into clearer focus, Californians directed more scrutiny toward their own and others’ water usage. Tighter water restrictions resulted in more water savings, but the demand for conservation also reawakened regional tensions throughout the state. While competition between urban, agricultural and environmental interests has long been an issue, the disparity in water use between richer and poorer communities has also drawn recent attention.

Californians were also expressing their adamant disapproval of the bottling and selling of the state’s water for a profit. Water bottlers, such as Nestle Waters North America, Starbucks and others, have been under pressure to stop bottling local water and look elsewhere for source water. Oregonians also have been working to keep Nestle from setting up shop to sell water from a drought-stricken part of their state.
Regional tensions linger in California’s drought,” by David Siders, The Sacramento Bee (Calif.), May 11, 2015
“DROUGHT: Water-bottling industry criticized in light of shortage,” by Janet Zimmerman, The Press-Enterprise (Riverside, Calif.), May 19, 2015
“Nestle Bottled-Water Plan Draws Fight in Drought-Stricken Oregon,” by Alison Vekshin, The Washington Post with Bloomberg, May 26, 2015

California ecosystem, wildlife threatened

The viability of some ecosystems was under threat because the devastation of one species can start a chain reaction of harm to other species. This situation was playing out on the Carrizo Plain northwest of Los Angeles with the near loss of the giant kangaroo rat. Kangaroo rats are part of a food chain that includes snakes, badgers, weasels, and birds of prey, and their digging loosens soil for insects. Drought has left the rodents mostly emaciated and starved. Many other species in California, Nevada and Arizona were also struggling to survive without adequate food and water sources.
“Animals in the wild are dying for a drink in the drought-stricken West,” by Darryl Fears, The Washington Post, May 6, 2015

Fish in Klamath River in Northern California in danger

Nearly all of the juvenile chinook salmon in the Klamath River were infected with a deadly parasite that thrives in warm, low rivers. Additional water releases could wash the parasite-laden worms down the river, but water stored in the Klamath Basin reservoirs was already set aside for endangered sucker fish and threatened coho salmon. The Klamath Fish Health Advisory Team said that a major fish kill is likely.
Drought leaves no water to combat salmon-killing parasite,” by Jeff Barnard, Associated Press, Monterey Herald (Calif.), May 20, 2015

Southern Great Plains

Rapid cattle herd expansion underway in southern Great Plains

Rain in the southern Great Plains improved pasture condition and promoted grass growth, necessary ingredients for ranchers to finally rebuild their cattle herds. A market analyst with CattleFax noted that the cattle herd was expanding very quickly and that more plentiful beef supplies are expected in 2016. Many years of drought in cattle-producing areas have kept livestock numbers down, but recent rainfall was paving the way for a fast rebound.
“Drenching rains green pastures, bode well for herd expansion,” by Roxana Hegeman, Associated Press, AgWeb (Mexico, Mo.), May 23, 2015


Drought affecting agriculture, wildlife and fire danger

The lack of rain has affected many aspects of life in Oregon. Farmers had to heavily replant wheat that did not germinate well. Low water levels at Detroit Lake State Recreation Area in northwestern Oregon closed boat ramps, while in the southern part of the state, forest officials warned visitors about the elevated fire danger in Fremont-Winema National Forest. An irrigation district in Deschutes County announced water allocations of just 30 percent of normal, while other irrigation districts also saw drastic cuts in water supplies. The dearth of water prompted the Oregon Drought Council to recommend seven additional county drought declarations to the governor. The counties in crisis include Deschutes, Grant, Jackson, Josephine, Lane, Morrow and Umatilla. Fourteen of the 36 counties in the state had already received drought declarations.
“Spring Wheat Crop Thins Out,” by Nate Birt, (Mexico, Mo.), May 8, 2015
“Oregon campgrounds open for Memorial weekend, but some reservoir levels very low,” by Terry Richard, Portland Oregonian, Hillsboro Argus, Oregon (Ore.), May 19, 2015
“Camping season at hand: national forest sends out these reminders,” by Terry Richard, Portland Oregonian, Hillsboro Argus, Oregon (Ore.), May 22, 2015
“Governor declares drought emergency for Deschutes County,” by Dylan J. Darling, Bend Bulletin (Ore.), May 23, 2015
“Drought Declarations for Umatilla and Morrow County Sent to Governor,” by Associated Press, KNDO Local News (Yakima, Wash.), May 15, 2015


Potentially harsh fire season ahead

State and federal fire officials alerted Nevada’s Gov. Sandoval that persistent drought, above-normal temperatures and dry vegetation could lead to a “perfect storm” for wildfires this summer. A spokesperson with the U.S. Forest Service stated, “We have been preparing for and have had dialogue on what [it] is going to look like when Southern California, Northern California, Nevada, Oregon and Washington all have simultaneous large fire events. The system is going to be heavily taxed this year.”
“Fire officials warn Sandoval of difficult summer,” by Ray Hagar, Reno Gazette-Journal (Nev.), May 5, 2015

Big game quotas adjusted

The Nevada board of Wildlife Commissioners lowered big game quotas for the 2015 hunting season due to drought. Quotas were reduced for mule deer, California bighorn sheep and, in some areas, pronghorn antelope. Drought and other factors led the board to cut back mule deer buck quotas by nearly 7 percent, compared to 2014.
“Big game tag quotas set, drought has impact,” by Nevada Department of Wildlife, Elko Daily Free Press (Nev.), May 21, 2015


Drought emergency for all of Washington State

Washington’s Governor Inslee declared a drought emergency for the entire state, smoothing the way for aid to those coping with water shortages. Record low snowpack and subsequent water shortfalls led agriculture officials to estimate a crop loss of $1.2 billion this year.

A difficult fire season could be looming this summer as hot, dry conditions raised the fire danger. The Department of Natural Resources sought additional funds because fire authorities worry that tinder dry conditions comparable to the 2014 summer could return, bringing massive wildfires.

The snow drought and record low river flow led the Washington State Department of Fish and Wildlife to draw up contingency plans to protect fish in its hatcheries. As of May 1, the mountain snowpack was 17 percent of average. Snowmelt runoff through September was expected to be the lowest in 64 years when official record keeping began.
Inslee declares statewide drought emergency,” by Associated Press and The Seattle Times, The Seattle Times, May 15, 2015
“Bad fire season expected on both sides of Cascades,” by Christopher Dunagan, The Herald (Everett, Wash.), May 4, 2015
“Washington's 'snow drought' puts fisheries at risk,” by Glenn Farley, KING5-TV, Seattle, USA Today, May 12, 2015
“Washington farmers, wildlife managers prepare for drought,” by Associated Press, Yakima Herald-Republic (Wash.), June 1, 2015

For additional drought information, visit the Drought Impact Reporter.

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