Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 305 PM EST Wed Dec 07 2022 Valid 00Z Thu Dec 08 2022 - 00Z Sat Dec 10 2022 ...Heavy rain and marginal flash flooding threat across the Central Plains through Thursday morning... ...Wintry weather spreading into the Central/Northern Plains tonight into tomorrow... ...Next round of heavy precipitation expected to reach the Pacific Northwest later tonight before spreading inland and down into California Thursday night into early Friday... A meandering front with a steady feed of low-level moisture continues to be the focus for disturbed weather across the south-central portion of the mainland U.S. over the next couple of days. Moderate to locally heavy rainfall is noted along and ahead of the slow moving cold front this afternoon over portions of the Southern Plains, through the Tennessee Valley, and into New England. Through tonight, an upper-level disturbance west of the ongoing showers is forecast to lift eastward and interact with a trailing portion of the front over the Southern Plains. This interaction is forecast to yield an uptick in excessive rainfall potential over portions of the Southern Plains and the Ozarks overnight, spreading into the Tennessee/Ohio Valley tomorrow. Isolated runoff issues are possible through tomorrow morning with this activity, denoted in the most recent WPC Excessive Rainfall Outlook that highlights a Marginal (level 1/5) risk of excessive rainfall generally from the Red River eastward through the Tennessee Valley. North of the heavy rainfall, temperatures will be cold enough to support mixed precipitation (including some freezing rain and drizzle) and snow over the Central/Northern Plains beginning early Thursday morning, where a few inches of snowfall are forecast through Friday morning. Winter Weather Advisories are in effect through Thursday evening over Northwest Kansas/Central Nebraska for freezing rain/drizzle potential tomorrow. The overall pattern supporting the wet weather from the southern Plains into the Northeast will also support much above average temperatures over the next few days over the Central to Southern Plains, and eastward into the East Coast. After numerous record high minimum and a few maximum temperatures were set yesterday over the Lower Mississippi Valley, a much more expansive area of potentially record high minimum (and a few daily maximum) temperatures are forecast to continue through Friday across portions of the Southern Plains, Lower Mississippi Valley, Tennessee Valley, Mid-Atlantic and Northeast. Looking toward the west, the next Pacific system arriving along the West Coast is on track to spread low elevation rainfall and heavy high elevation snows to the Pacific Northwest into Central California beginning tonight. The current WPC Winter Storm Severity index now reflects Moderate to locally Major potential winter storm impacts in elevation over the Olympics and Cascades tomorrow through Friday, where snowfall accumulations in excess of a foot could fall. As of this afternoon, a slew of Winter Weather Advisories are in effect over the Cascades through early Friday morning for this expected snowfall. Asherman/Kong Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php