National Drought Summary -- June 19, 2018

The discussion in the Looking Ahead section is simply a description of what the official national guidance from the National Weather Service (NWS) National Centers for Environmental Prediction is depicting for current areas of dryness and drought. The NWS forecast products utilized include the HPC 5-day QPF and 5-day Mean Temperature progs, the 6-10 Day Outlooks of Temperature and Precipitation Probability, and the 8-14 Day Outlooks of Temperature and Precipitation Probability, valid as of late Wednesday afternoon of the USDM release week. The NWS forecast web page used for this section is: http://www.cpc.ncep.noaa.gov/products/forecasts/.

An active weather pattern brought rain to areas of the northern Rocky Mountains, northern Plains, Upper Midwest and Southwest and along the Gulf Coast from Texas to Florida. The rain in the Southwest was from the remnants of tropical storm Bud, which came up the Gulf of California and brought much-needed moisture into the region. Tropical moisture also flowed inland off the Gulf of Mexico, bringing heavy coastal rains at the end of the current U.S. Drought Monitor period. A series of events brought heavy rains from Montana to Wisconsin along the northern tier of the country, with up to 6-8 inches of rain over much of Wisconsin for the week. Temperatures for the week were at or above normal for most of the country, with only the northern Rocky Mountains, portions of the Southwest, and the Eastern Seaboard being below normal. Areas of the Plains had triple-digit heat, with areas of Nebraska and Kansas having departures of 6-10 degrees above normal for the week.


Alaska, Hawaii, and Puerto Rico

No changes were made in Hawaii this week as precipitation has been near normal over most all the islands. In Puerto Rico, dryness continues to develop and abnormally dry conditions were expanded to the north by about 1 county this week. Hydrological and ecological impacts due to lingering dryness over the panhandle of Alaska has also allowed for the expansion of abnormally dry conditions there this week.


High Plains

The northern portions of the region were cooler than normal with widespread rain over the western Dakotas while most of the rest of the region had temperatures that were 6-9 degrees above normal, and most areas from central and eastern Nebraska into eastern Kansas were drier than normal for the week. Precipitation amounts that were 1-2 inches above normal fell along the Nebraska and South Dakota border and in and around the Omaha metro area in eastern Nebraska. Improvements were made over most of northern and western North Dakota, where moderate and severe drought was improved and the extent of the abnormally dry areas was also reduced. A full category improvement was also made over western South Dakota as the short-term pattern has brought enough precipitation that only lingering long-term issues remain. The impact designation over the western Dakotas was also changed to long-term. In eastern South Dakota, the short-term dryness as well as the heat allowed for the expansion of both moderate drought and abnormally dry conditions to the south. Moderate drought was expanded in southeast Nebraska along the Kansas border. Moderate drought and abnormally dry conditions were improved in far eastern Nebraska this week as well.

Extreme drought was removed from southwest Kansas as the drought indicators and indices did not support extreme drought with the influx of the most recent rains. Impacts remain, especially in the agricultural sector. In eastern Kansas, abnormally dry and moderate drought conditions were expanded as the region continues to miss out on the rain events and the recent heat has rapidly worsened conditions.


Midwest

An unseasonably warm week across the region was also coupled with widespread rain, especially over the upper Midwest. Temperatures were 5-7 degrees above normal, with the warmest readings over Missouri. Most all areas were near normal precipitation for the week, with portions of northern Wisconsin and northern Minnesota having rain totals of 3+ inches above normal. Some local totals were: 5.17 inches in Rhinelander, WI; 4.42 inches in Wausau, WI; 4.02 inches in Green Bay, WI; 3.07 inches in Marshfield, WI; and 3.06 inches in Oshkosh, WI. The widespread heavy rains allowed for the removal of much of the abnormally dry designation over the upper peninsula of Michigan, all of Wisconsin and most of Minnesota. There was a small improvement to abnormally dry conditions in central and western Iowa as well. Missouri has continued to dry over the last several months, with agricultural-related impacts becoming more widespread. Changes this week in Missouri include expansion of severe drought over the northern portion of the state as well as the expansion of moderate drought and abnormally dry conditions in the northeast that included far western Illinois. Abnormally dry conditions were also expanded over much of western Missouri and a new pocket was introduced in southeast Missouri. Abnormally dry conditions were also expanded slightly in eastern Iowa along the Mississippi River.


Northeast

A cool and mostly dry week for the region, with some rain coming at the end of the current period. Temperatures were 1-2 degrees below normal from Virginia to southern New England. Almost the entire region was drier than normal for the week, with the driest areas along the Atlantic coast. Abnormally dry conditions were expanded over much of New England this week as long-term hydrological issues along with short-term dryness have impacted the region.


South

Most of the region was near normal precipitation for the week, with portions of west Texas and areas along the Gulf Coast receiving above-normal precipitation. Some areas of south Texas and near the Louisiana border were 5-7 inches above normal for the week as tropical moisture flowed onshore, bringing good coastal rains. Widespread improvements were made over western Texas and into the panhandles of both Texas and Oklahoma, with a full category improvement where the best rains occurred. A full category improvement was also made along most coastal areas from southern Texas and into Louisiana. Degradation took place over much of eastern Texas and Oklahoma, Arkansas and northwest Louisiana. The short-term dryness and heat has allowed for drought to continue to develop quite rapidly. A large area of severe drought was introduced this week over southeast Oklahoma, northeast Texas and into southwest Arkansas. Moderate drought filled in most of east Texas and more of northwest Louisiana and southwest Arkansas.


Southeast

The region continues to receive spotty, mainly convective, thunderstorm activity as the source of the precipitation in the region. Areas that are missing out on these events are drying out as the heat of the summer is well established in the region, with most areas 2-4 degrees above normal for the week. The panhandle of Florida and southern Alabama and Georgia had temperature departures of 1-2 degrees below normal for the week with the most active precipitation pattern. The only changes this week was a small expansion of D0 in northern Alabama.


West

Most of Montana has been quite wet over both the short- and long-term, but there are pockets of dryness remaining and developing in the northwest portion of the state. Widespread precipitation over much of eastern Idaho, Wyoming, and southern Montana has kept these areas drought free. Tropical moisture came up the Gulf of California and into the Southwest over the weekend, bringing cooler temperatures and widespread precipitation over both Arizona and New Mexico and into central Colorado. No changes were made in Arizona, but the rains allowed from some improvement to the severe and extreme drought over eastern New Mexico as well as some minor improvements in southeast Colorado. Abnormally dry conditions were introduced into northwest Montana, northern Idaho and extreme northeast Washington while moderate drought was introduced into north central Montana.


Looking Ahead:

Over the next 5-7 days, an active weather pattern continues to slowly move east out of the Plains and into the Midwest, bringing with it cooler temperatures and very heavy rain. The areas forecast to have the greatest precipitation are in the northwest portions of Iowa southeast into southern Indiana, the Gulf coast of Texas, and northeast Oklahoma, northwest Arkansas, and southwest Missouri. Much of the eastern two-thirds of the country is expecting precipitation while the West and Southwest will remain dry. Temperatures will remain below normal in the areas of the Plains and Midwest where the greatest precipitation occurs while the West and Southwest should expect daily high temperatures to be 8-10 degrees above normal.

The 6-10 day outlooks show that the chances for above-normal temperatures remain quite high over most of the United States, with the exception of Alaska, the northern Rocky Mountains and the Pacific Northwest. The wet pattern looks to continue as the central and northern Plains, Midwest, and South all are showing above-normal chances of recording above-normal precipitation, with the greatest chances over the Midwest. Higher than normal chances of below-normal precipitation look to be projected from the Pacific Northwest southeast into Texas during this time as well.


Author: Brian Fuchs, National Drought Mitigation Center

Dryness Categories
D0...Abnormally Dry...used for areas showing dryness but not yet in drought, or for areas recovering from drought.

Drought Intensity Categories
D1...Moderate Drought
D2...Severe Drought
D3...Extreme Drought
D4...Exceptional Drought

Drought or Dryness Types
S...Short-term
L...Long-term