Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 354 AM EDT Tue Mar 30 2021 Valid 12Z Tue Mar 30 2021 - 12Z Thu Apr 01 2021 ...Heavy rain and scattered flash flooding to impact the Lower Mississippi and Tennessee Valleys over the next few days... ...Showers and thunderstorms to spread across the Southeast and Mid-Atlantic on Wednesday... ...Developing low pressure system across New England to bring coastal rain and inland light snow throughout the Northeast Wednesday night into Thursday morning... The focus for much of the active weather across the central and eastern U.S. over the next few days will be along a strong cold front as it completes its trek across the country. Gusty winds across the Northern and Central Plains will slowly relax by this evening well behind the front. Temperatures 10 to 20 degrees below average will also follow its wake. Farther south, as the cold front pushes across the southern High Plains and Southwest, gusty winds and low relative humidity could make conditions ideal for wildfires to spread uncontrollably. Red Flag Warnings are in effect across southeast Arizona, southern/central New Mexico, as well as West Texas. Meanwhile, a warm front lifting north out of the Gulf of Mexico today will usher in an abundance of moisture to the Lower Mississippi Valley and lead to showers and thunderstorms developing along and ahead of the aforementioned cold front. Heavy rain is forecast to spread across the Tennessee Valley by this evening and last into Wednesday morning. Total rainfall amounts of 1 to 3 inches could lead to flooding concerns from southern Arkansas to Middle Tennessee. Much of this region has experienced well above average rainfall over the last week; therefore, any additional heavy rain will likely cause rivers to overflow their banks quickly. Low-lying areas prone to flooding are likely to see the most impacts. WPC has issued a Slight Risk of Excessive Rainfall that includes southern Arkansas, northern Mississippi, and west/middle Tennessee. A few thunderstorms will also have the potential to produce damaging wind gusts and large hail. The Storm Prediction Center has issued a Marginal Risk of severe weather across much of the Lower Mississippi and Tennessee valleys today. By Wednesday, showers and thunderstorms will slowly exit the Tennessee Valley and enter the Southeast and Mid-Atlantic. A few isolated instances of flash flooding will be possible from the southern Appalachians to the Mid-Atlantic. Severe weather will also be a concern from Louisiana to Delaware on Wednesday, where SPC has issued a Marginal Risk of severe thunderstorms. As the cold front reaches the Mid-Atlantic coast Wednesday evening, an area of low pressure is forecast to develop and strengthen as it swings northeast toward New England. This will help usher in much cooler temperatures behind the cold front, while also focusing moderate rain along the coast. Rain is likely to changeover to snow across interior portions of the Northeast and Lower Great Lakes as temperatures quickly drop to near and below freezing Wednesday night. A few inches of wet snow are expected by Thursday morning, mainly across western and northern New York State. Snell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php