Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 356 AM EDT Sat Mar 30 2019 Valid 12Z Sat Mar 30 2019 - 12Z Mon Apr 01 2019 ...Potentially heavy rain and thunderstorms are likely across the Ohio and Tennessee Valleys on Saturday... ...A cold front will usher in cooler temperatures for the eastern U.S. on Sunday after a warm Saturday, while the West warms... A strong cold front is expected to move through the Mississippi and Ohio Valleys on Saturday and through the Eastern Seaboard on Sunday, causing active weather along it. Widespread rain and thunderstorms are forecast for the Lower Mississippi Valley northeastward through the Ohio Valley on Saturday. A Slight Risk of excessive rainfall is in place for portions of the Ohio Valley that are expecting the heaviest rain totals, while the Storm Prediction Center has outlooked a Slight Risk of severe weather in the Tennessee Valley on Saturday. Rain will spread to the Eastern Seaboard by Sunday morning as the front progresses. Snow is also expected along the northwestern side of a low moving along the front through the Lower Great Lakes region and into southeastern Canada. A swath of 4 to 6 inches of snow is forecast for the Lower Great Lakes region into parts of northern New England through Sunday night, and light freezing rain is possible there as well. After the front passes, precipitation should dry out in most areas, but rain showers could continue in the Gulf Coast states through Monday morning with sufficient moisture from the Gulf. Farther west, an upper-level low is forecast to move slowly through the Four Corners region through the weekend, which will allow some snow to accumulate in the Central and Southern Rockies. 4 to 8 inches of snow is possible in the higher elevations of the San Juan Mountains. By Sunday night, light snow is expected to form in the Northern Rockies and Northern High Plains, associated with a surface low. Another low approaching the West Coast will increase rain chances late Sunday in the Pacific Northwest after a dry period. On Saturday, high temperatures will be 15 to 25 degrees below normal in the Central/Southern Plains to Middle Mississippi Valley behind the strong cold front. Ahead of the front, the East is expecting temperatures 10 to 20 degrees above average on Saturday, but by Sunday, the Ohio and Tennessee Valleys will see high temperatures 10 to 20 degrees below average, which is a large temperature swing between Saturday and Sunday. The West Coast is expected to warm up and be around 10 degrees above average this weekend. Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php