Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 254 AM EST Wed Dec 30 2020 Valid 12Z Wed Dec 30 2020 - 12Z Fri Jan 01 2021 ...Heavy snow for Iowa, Southern Wisconsin, and West-Central Michigan... ...There is a Slight Risk of excessive rainfall over parts of the Southern Plains into parts of the Lower Mississippi Valley... ...Winter storm over the Midwest to wind down... ...Rain/Freezing rain from the Central Plains into Middle Mississippi Valley on Thursday... ...Heavy snow for the Cascades and the Northern Intermountain Region... A front extending from the Great Lakes to the Southern Plains will move eastward to the Northeast Coast and extend southwestward to the Western Gulf Coast by Thursday. Winter storm over the Midwest to wind down on Wednesday, as rain and snow move into the Northeast on Wednesday afternoon into late Wednesday night. Overnight Wednesday, rain and snow move into parts of the Mid-Atlantic, change over to all rain by Thursday afternoon. In the meantime, rain and embedded thunderstorms develop over parts of the Southern Plains and rain into the Middle Mississippi Valley. Snow will develop over the Texas Panhandle. The WPC has issued a Slight Risk of excessive rainfall over parts of the Southern Plains into parts of the Lower Mississippi Valley on Wednesday into Thursday morning, continuing into New Yearâ€s Day. Heavy rain associates with the storm will help produce scattered areas of flash flooding over the area, with urban areas, roads, and small streams having the greatest possibility for flash flooding. Isolated significant areas of flash flooding are possible. On Thursday, a wave of low pressure over the Western Gulf Coast will move northeastward, developing into a storm over the Southern Plains/Lower Mississippi Valley on New Yearâ€s Day. The system will produce rain over parts of the Southern Plains and showers and thunderstorms over the Western Gulf Coast, while snow continues over Western Texas. On Thursday, rain/freezing rain areas will develop over parts of the Southern Plains that will move into parts of the Central Plains/Middle Mississippi Valley overnight Thursday into New Yearâ€s Day. The possibility exists for 0.25 inches of ice developing over the region Thursday night into New Yearâ€s Day. Showers and thunderstorms will develop over parts of the Lower Mississippi Valley Thursday evening, moving into parts of the Tennessee Valley/Central Gulf Coast by New Yearâ€s Day. In addition, rain will move into parts of the Southeast and Southern Mid-Atlantic also on New Yearâ€s Day. Meanwhile, a front moving into the Pacific Northwest moves inland to the Northern Intermountain Region to Central California and dissipating by Thursday. The system will produce coastal rain and higher elevation snow over the Northwest, expanding into parts of Northern California and the Northern Intermountain Region by Wednesday evening. The snow moves into parts of the Great Basin by Thursday. The snow winds down overnight Thursday over the Pacific Northwest and the Northern Intermountain Region/Great Basin. Rain continues over Coastal Northwest on New Yearâ€s Day. Snowfall amounts maybe 12 to 18 inches over the Cascades and the Northern Intermountain Region. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php