Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 537 AM EDT Thu May 07 2020 Valid 12Z Thu May 07 2020 - 12Z Sat May 09 2020 ...A late-season snowstorm becomes increasingly likely for the interior Northeast beginning Friday and culminating on Saturday... ...Near record heat continues across the Desert Southwest as a surge of abnormally cold air pushes south into much of the eastern U.S. on Saturday... An unusual weather pattern evolving across North America will lead to widespread rain and thunderstorms to move across the central and eastern U.S. before a late-season snowstorm becomes increasingly likely for the interior Northeast by the weekend. The low pressure system associated with this event is currently in the developmental stage across the High Plains. A Pacific front that has moved through the western U.S. is forecast to interact with a stationary front, leading to the formation of a low pressure system over the central Plains later today. A swath of rain and high-elevation snow across the northern Rockies this morning will quickly expand eastward into the central Plains ahead of the developing system where severe thunderstorms will be possible by tonight. The vigorous dynamics associated with the developing system will likely bring a period of enhanced rainfall and thunderstorms eastward through the Mid-Mississippi and Ohio Valleys on Friday while severe thunderstorms are possible across the Deep South. In the mean time, an unusually cold air mass for this time of the year is forecast to plunge southward into the Great Lakes toward the eastern U.S. This will set the stage for a late-season snow event for the interior Northeast beginning on Friday as the low pressure system continues to intensify while moving quickly across the Tennessee Valley into the central Appalachians. Rain can be expected to change over to wet snow, possibly heavy, over the central Appalachians on Friday before blustery winds and colder air ushering in on the back side of the storm. By Friday night, the low pressure system is forecast to further intensify as the storm center skirts the New England coast. It appears that interior New England will see significant amount of wet snow with northerly winds becoming increasingly strong and gusty late Friday night into Saturday morning. The unusually cold air mass from eastern Canada will be pulled southward down into the eastern U.S. behind the storm, resulting in widespread record low temperatures spanning as far south as Alabama and Mississippi on Saturday. This will be in stark contrast with near record heat across southern California, the Desert Southwest, and the southern Rockies. In addition, fire danger will be very high today over much of the southern Rockies as the low pressure system develops over the central Plains. Lowering humidity and gusty winds will also help elevate the risk of wildfires over parts of Florida. Meanwhile, the Pacific Northwest will catch a break in precipitation as a gradual warming trend sets in. Lastly, an Alberta clipper is forecast to spread rain and mixed wintry precipitation into the northern Plains and parts of the northern Rockies Friday into Saturday morning. Kong Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php