Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 252 AM EST Tue Feb 19 2019 Valid 12Z Tue Feb 19 2019 - 12Z Thu Feb 21 2019 ...Unsettled weather pattern developing across the south-central part of the nation through midweek... An active weather pattern is returning to much of the eastern U.S. after a brief dry spell on Monday. The next storm system is developing over the western Gulf of Mexico today and will extend northward along a frontal zone by early Wednesday. There will be a deep northward surge of moisture from the Gulf, and the frontal boundary will lift this moisture and generate a corridor of copious rainfall from Louisiana to eastern Kentucky, with widespread 2 to 5 inch rainfall amounts expected by Thursday morning. With much of this falling on already moist ground from the rainfall this past weekend, flooding will be a concern and a moderate risk of excessive rainfall exists over parts of that region. Some strong thunderstorms may also develop across parts of the Deep South. Farther to the northeast, snow and freezing rain are expected for the central Appalachians and the northern Mid-Atlantic by late Tuesday night and into Wednesday as moisture intersects a cold airmass in place. Several inches of snow is likely before changing to sleet and freezing rain, mainly along and west of Interstate 95. Significant icing is possible for some inland valley locations. More moderate to heavy snow is expected across the Cascades and northern Rockies for the middle of the week. Winter storm warnings and winter weather advisories are in effect for these areas with the potential for snowfall amounts in excess of 8 inches for the higher mountain ranges. The next round of snow begins arriving to southern Utah and northern Arizona by Thursday. Elsewhere across the continental U.S., very cold temperatures are expected from Montana to Minnesota with highs in the teens and low 20s with a large arctic surface high from Canada in place and slowly moving eastward. Wind chill advisories are in effect for some areas. Across the central plains and Upper Midwest, moderate to locally heavy snow is forecast on Tuesday and into Wednesday on the backside of the developing surface low. D. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php