Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 158 PM EDT Sat May 25 2019 Valid 00Z Sun May 26 2019 - 00Z Tue May 28 2019 ...Additional rounds of severe weather and flash flooding are expected for the Memorial Day weekend across portions of the central and southern Plains along with the Midwest... ...Record heat and dry weather is expected across the Southeast U.S. into early next week... ...Very cool and unsettled weather continues for the West... Generally no big changes to the prevailing weather pattern are expected across the country for this Memorial Day weekend. Active weather is forecast to continue across the central part of the nation through the Memorial Day holiday. This will again be in response to a strong upper level trough reloading over the Intermountain West and the presence of a large upper level ridge positioned over the southeastern U.S. A strong clash of air masses from the southern Plains to the Ohio Valley region will support additional rounds of severe weather along with the threat for more flash flooding over areas that have already seen record flooding over the last couple of weeks. All of this will be focused along a slow moving frontal boundary where multiple waves of low pressure will be developing and riding along it. One low pressure system is currently exiting the Great Lakes region and lifting across southeast Canada. This will drive a cold front through the upper Midwest and Great Lakes region by this evening, but the southwestern portion of this boundary will stall out and be draped well southwest down across the central and southern High Plains. Numerous heavy showers and thunderstorms will focus along this front this evening through Sunday, bringing multiple rounds of severe weather including the threat of very large hail, damaging winds and tornadoes. In addition to the severe weather, flash flooding will be a strong concern as well. In fact, the Storm Prediction Center currently has an Enhanced Risk area of severe weather highlighted for this evening from the Texas and Oklahoma panhandles northeast across adjacent areas of western Oklahoma and southwest Kansas. On Sunday, there is an Enhanced Risk area that shifts farther northwest and extends from the northern Texas panhandle up across far eastern Colorado, western Kansas and into southwest Nebraska. Therefore, it is expected to be an active weekend with strong to severe thunderstorms again appearing likely. Heavy rainfall from the multiple rounds of thunderstorms will aggravate ongoing flooding and runoff problems across much of the central Plains and adjacent areas of the middle Mississippi Valley. Consequently, the Weather Prediction Center has highlighted a Moderate Risk of excessive rainfall for these areas. In terms of temperatures, readings will continue to be well below average for a large area of the Intermountain West, but also for areas out across the northern Plains, upper Midwest and over through parts of the Northeast as a cold front settles to the south and cooler air filters down from Canada. The chilly weather out in the West will be highly connected to the aforementioned upper trough reloading and also extensive cloudiness and shower activity. In some cases, temperatures will be over 20 degrees below normal. Meanwhile, across portions of the Tennessee Valley, the Deep South and the Southeast, very dry conditions and record high temperatures are expected through Memorial Day as high pressure overhead will yield high temperatures soaring well into the 90s to near 100 degrees which will be as much as 10 to 15 degrees above normal. Orrison Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php