Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 408 PM EDT Sat Apr 05 2025 Valid 00Z Sun Apr 06 2025 - 00Z Tue Apr 08 2025 ...There is a High Risk of excessive rainfall over parts of the Middle/Lower Mississippi Valley and the Ohio/Tennessee Valleys on Saturday; there is a Slight Risk of excessive rainfall over parts of the Ohio/Tennessee Valleys, Southern Appalachians, and the Southeast on Sunday... ...There is a Moderate Risk of severe thunderstorms over parts of the Lower Mississippi Valley and Tennessee Valley on Saturday; there is a Slight Risk of severe thunderstorms over parts of the Southern Appalachians and Central Gulf Coast/Southeast on Sunday... ...Light snow over parts of the Northeast on Saturday; Freezing rain over parts of Northern New England on Saturday; light to moderate snow over the Upper Great Lakes and light snow over the Northeast on Sunday... On Saturday, a front extending from the Lower Great Lakes to the lower Mississippi Valley/Western Gulf Coast will move eastward, with the northern portion of the front moving off the Northeast/ northern Mid-Atlantic Coast by Monday evening while the southern half lingers over the southern Mid-Atlantic/Southeast. Moisture flowing northward out of the Gulf of America will intersect the boundary, producing life-threatening rain over parts of the Middle/Lower Mississippi Valley and the Ohio/Tennessee Valleys. Therefore, the WPC has issued a High Risk (level 4/4) of excessive rainfall over parts of the Middle/Lower Mississippi Valley and the Ohio/Tennessee Valleys through Sunday morning. Severe, widespread flash flooding is expected. In addition, areas that normally do not experience flash flooding will flood. Furthermore, lives and property are in great danger. Moreover, showers and severe thunderstorms will develop along and ahead of the front from parts of the Ohio Valley to the Lower Mississippi Valley/Western Gulf Coast. Therefore, the SPC has issued a Moderate Risk (level 4/5) of severe thunderstorms over parts of Lower Mississippi Valley and Tennessee Valley through Sunday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Additionally, there is an added threat of EF2 to EF5 tornadoes and hail two inches or greater over parts of the Tennessee Valley and Lower Mississippi Valley, as severe thunderstorm wind gusts of 65 knots or greater over parts of the region. On Sunday, as the front moves eastward, the area of heavy rain moves eastward to the Ohio/Tennessee Valleys, Southern Appalachians, and the Southeast. Therefore, the WPC has issued a Slight Risk (level 2/4) over parts of the Ohio/Tennessee Valleys, Southern Appalachians, and the Southeast from Sunday into Monday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and low-lying areas the most vulnerable. Likewise, the threat of severe thunderstorms moves eastward and reduces slightly over parts of the Southern Appalachians and Central Gulf Coast/Southeast on Sunday. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe thunderstorms over the Northern/Central Plains and the Upper/Middle Mississippi Valley from Sunday through Monday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, a few tornadoes, and a minimal threat of hail. On Monday, the threat of severe thunderstorms and excessive rainfall will be a minimal risk over parts of the southern Mid-Atlantic and Southeast. Moreover, showers and thunderstorms will develop over parts of the northern Mid-Atlantic to Southern New England on Saturday, with rain over parts of the Northeast. Snow will develop over parts of Northern New England. Along the rain-snow line, rain/freezing rain areas will develop, producing ice accumulation of up to 0.10 inches from late Saturday afternoon into Sunday morning. Further, light rain and snow will develop over parts of the Southern Plains on Saturday. Meanwhile, on Saturday, another developing over Central Canada will move southeastward to the Lower Great Lakes, the Lower Mississippi Valley/Southern Plans, and then northwestward to the Northern Rockies by Monday evening. The system will produce light to moderate snow over the Upper Great Lakes and, to a lesser extent, the Upper Mississippi Valley starting early Sunday morning through Monday evening. Light snow will also develop over parts of the Lower Great Lakes/Northeast, starting overnight on Sundays and going into Monday evenings. Furthermore, a third front will move onshore over the Pacific Northwest on Sunday, advancing inland to the Northern Intermountain Region and then dissipating by Monday. However, a fourth front will move onshore over the Pacific Northwest on Monday into Monday afternoon. The systems will produce light rain over the Northwest Coast early Sunday morning into Sunday afternoon. As the front moves inland, the rain will move farther inland into the Northwest and start over Northern California by late Sunday afternoon. As the boundary moves farther inland, the rain moves into the Northern Intermountain Region, and light snow at the highest elevations of the Cascades. Ziegenfelder Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php