Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 PM EDT Fri Apr 23 2021 Valid 00Z Sat Apr 24 2021 - 00Z Mon Apr 26 2021 ...Flash flooding and severe weather potential will spread from the south-central U.S. this evening and tonight into the Southeast on Saturday... ...Rain and snow increasing across the West this weekend... ...Ongoing fire weather danger is expected for the Four Corners states to the Southern High Plains... A surface low pressure system and its associated fronts are forecast to move from the Southern Plains eastward into the Southeast on Saturday. Moisture flowing in from the Gulf of Mexico combined with these features will continue to produce rain and thunderstorms across those regions. Through tonight, a Moderate Risk of excessive rainfall is in place for central Louisiana and southwestern Mississippi as multiple inches of rain training over that area could lead to numerous flash floods, some of which could be locally significant. Marginal to Slight Risks of flash flooding as well as Enhanced Risks of severe weather are also in place for portions of the Southern Plains, Lower Mississippi Valley, and the Southeast through tonight. The Southern Plains in particular could see damaging hail of greater than 2" in diameter with these storms. Then on Saturday, thunderstorm chances shift to the Southeast. Slight to Enhanced Risks of severe weather are delineated for the Southeast into the Carolinas for tornado, high wind, and hail threats, with flash flooding possible as well. By Saturday night and Sunday, the low pressure system is forecast to deepen over the Atlantic and move northeastward, leading to rain showers across the Mid-Atlantic and Northeast. Across the western U.S., a couple of rounds of upper-level energy and troughing will push frontal systems into the region and help cause precipitation there, beginning in the Pacific Northwest tonight and expanding south and eastward into the Northern Rockies, Great Basin, and California through the weekend. Precipitation will generally be in the form of snow in higher elevations and rain in lower elevations. The Sierra Nevada is likely to see the heaviest snow through Sunday, with over a foot expected, and Winter Storm Warnings are in place there. Elsewhere, the north-central U.S. could see light precipitation tonight into Saturday as a front passes through, with light mixed precipitation or snow possible in parts of the Northern Plains, Upper Midwest, and Upper Great Lakes. Rain is likely farther south in the Ohio Valley between the two frontal systems. Then another round of snow could occur across the north-central region again by Sunday with cooler than normal temperatures north of a warm front. Meanwhile, conditions in the southwestern U.S. look to remain dry over the next couple of days. Dry conditions with low relative humidities and dry ground, as well as enhanced gusty winds from the approaching upper-level troughing, will lead to ongoing fire danger for the Four Corners states into western Texas. A Critical Risk of fire weather is in place today for the Southern High Plains, with Elevated Risks stretching back into the Four Corners today and Saturday. Another round of dangerous fire weather conditions can also be expected early next week. Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php