Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 356 AM EDT Tue Mar 29 2022 Valid 12Z Tue Mar 29 2022 - 12Z Thu Mar 31 2022 ...Severe thunderstorms and excessive rainfall threat on Tuesday into Thursday morning... ...Much below-average temperatures are expected from the Great Lakes into the Northeast/Mid-Atlantic, with records low temperatures possible on Tuesday... ...There is an Extreme Risk of fire weather over parts of the Southern High Plains on Tuesday... A deep upper-level trough over the Great Lakes to the Northeast moves eastward, which will allow temperatures to be 10 to 20 degrees below average over the region. As a result, the Tuesday s morning low temperatures will be a record or tied for a record low temperatures over several parts of the Great Lakes to the Northeast/Mid-Atlantic Coast, which will start to moderate during the day. Meanwhile, a broad, deep upper-level low over Southern California to the Southwest on Tuesday will move steadily to the Mississippi Valley/Great Lakes by Thursday. Therefore, scattered light rain and higher elevation snow will develop over parts of Southern California to the Rockies through Wednesday morning. Furthermore, as the storm moves out of the Rockies overnight Tuesday, moisture will begin to flow northward over the Plains and Mississippi Valley. The moisture will aid in producing showers and thunderstorms over parts of the Central/Southern Plains and parts of the Middle/Lower Mississippi Valley. Some of the thunderstorms will become severe. Therefore, from Tuesday into Wednesday morning, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Central/Southern Plains and parts of the Middle/Lower Mississippi Valley. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Moreover, the WPC has issued a Marginal Risk of excessive rainfall with these thunderstorms over the area on Tuesday into Wednesday morning. Furthermore, rain and snow will develop over parts of the Northern Plains also overnight Tuesday. An area of light rain/freezing rain will develop over a wide area from the Upper Mississippi Valley to the Great Lakes and parts of the Central Appalachians overnight Tuesday into Thursday. Likewise, snow and rain/freezing rain will develop over parts of Northern New England overnight Wednesday into Thursday morning. Additionally, the threat of severe thunderstorms and excessive rainfall increases from Wednesday into Thursday morning. As the system moves eastward, the SPC has issued a Moderate Risk of severe thunderstorms over the Lower Mississippi/Tennessee Valleys and the Southeast on Wednesday into Thursday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Over the Central Gulf Coast, Lower Mississippi/Tennessee Valleys, and the Southeast, there is an increased threat of EF2-EF5 tornadoes and severe thunderstorm wind gusts of 65 knots or greater. Moreover, due to the associated heavy rain, the WPC has issued a Slight Risk of excessive rainfall over parts of the Tennessee Valley/Southeast from Wednesday to Thursday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable through Sunday morning. In addition, the SPC has issued an Extreme Risk of fire weather over parts of the Central/Southern High Plains Tuesday into Wednesday morning due to strong gusty winds, low relative humidity, and dry fuels. The threat reduces to a Critical Risk of fire weather on Wednesday into Thursday morning over the southern third of Texas. Ziegenfelder Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php