Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 AM EDT Thu Oct 11 2018 Valid 12Z Thu Oct 11 2018 - 12Z Sat Oct 13 2018 ...Tropical Storm Michael will bring life-threatening flash flooding, heavy rain, and strong winds to the Carolinas into Virginia today... ...Heavy rain is likely in the Mid-Atlantic and Northeast today... ...Cool temperatures and snow possible in the Central U.S.... ...Rains ahead of Sergio will begin on Friday for the Southwest to Southern Plains... Tropical Storm Michael will continue to bring dangerous conditions as it tracks through the Carolinas and into southeastern Virginia today. Intense rainfall rates combined with wet antecedent conditions has led to the issuance of a High Risk of excessive rainfall/flash flooding for much of North Carolina and into southern Virginia. 3 to 6 inches of rain, with isolated maximum amounts of 8 inches, are expected there. Tropical storm force winds are of course still a threat, and the Storm Prediction Center has indicated isolated tornadoes are possible in the eastern Carolinas and southeastern Virginia today. Please refer to the National Hurricane Center for the latest information on the track and intensity of Michael. To the west of Tropical Storm Michael, a cold front will move eastward through the Appalachians on Thursday and clearing the Eastern Seaboard by Friday morning. As tropical moisture streams ahead of the front, heavy rainfall is possible on Thursday north of Michael itself. Slight to Moderate Risks of flash flooding are in place along the Mid-Atlantic and southern New England coasts. Behind this cold front, the eastern U.S. will finally see fall-like temperatures for the end of the week. An upper-level trough in the western U.S. and another surface front will help support snowfall formation in the Central Rockies on Thursday, with 6 to 10 inches possible in the highest elevations. Some light snowfall is possible in the Central Plains and Middle Mississippi Valley by Friday morning, with cooler than normal temperatures there. In fact, high temperatures in the Northern and Central Plains and Upper Mississippi Valley are forecast to be 15 to 25 degrees below average on Thursday, and widespread Freeze Warnings are in effect for the cold mornings. By Friday night and Saturday, snow is possible in the Northern Rockies and Northern Plains as a low pressure system approaches. Per the National Hurricane Center, Tropical Storm Sergio is forecast to move eastward and make landfall in Baja California around Friday morning. Moisture streaming ahead of Sergio will cause rainfall to begin in the Southwest U.S. by Friday, and as Sergio continues moving northeast, spread into the Southern Plains. Please see the NHC's website for the latest on Sergio. Tate Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php