Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 335 AM EDT Sun Oct 09 2022 Valid 12Z Sun Oct 09 2022 - 12Z Tue Oct 11 2022 ...There is a Slight Risk of excessive rainfall over parts of the Southwest, Southern Rockies, and western Texas through Monday morning... ...There is a Slight Risk of excessive rainfall over parts of the Southern High Plains from Monday into Tuesday morning... ...There are Frost Advisories and Freeze Warnings over parts of the Ohio Valley/Central Appalachians, Mid-Atlantic, and Northeast... Upper-level energy over Northwestern Mexico and a surge of moisture moving northwestward over the Southern Plains from the Gulf of Mexico will produce showers and thunderstorms with heavy rain over parts of southeast Arizona, southern New Mexico, and western Texas. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms over parts of the Southwest, Southern Rockies, and far western Texas through Monday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and burn scars the most vulnerable. On Monday, The threat of excessive rainfall moves slightly eastward to the Southern High Plains. Therefore, the WPC has issued a Slight Risk of excessive rainfall with these thunderstorms over parts of the Southern High Plains from Monday into Tuesday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, small streams, and burn scars the most vulnerable. Meanwhile, high pressure over the Mid-Atlantic, Tennessee Valley, and Southern Plains will move into the Mid-Atlantic and start to move over the Western Atlantic by Tuesday. The high pressure will produce clear skies and calm wind, allowing temperatures to go below or near freezing on Sunday morning. As a result, large parts of the Ohio Valley/Central Appalachians, Mid-Atlantic, and Northeast have Frost Advisories out until 8-9 AM local time. Furthermore, parts of the far Eastern Ohio Valley and Central Appalachians have Freeze Warnings out through 10 AM local time on Sunday morning. Moreover, the relatively cold air flowing over the relatively warm Great Lakes will produce lake effect rain showers downwind from Lakes Ontario and Erie through late morning Sunday. Furthermore, a front over Upper Midwest will move off the Northeast Coast by Monday morning while extending westward to the Middle Mississippi Valley. The boundary will aid in producing light rain over parts of the Upper Midwest on Sunday morning. In addition, light rain will develop along the front over parts of the Great Lakes into parts of Northern New England from Sunday afternoon into Monday morning. Additionally, a front moving onshore over the Pacific Northwest overnight Monday will move to the Northern High Plains by Tuesday. As a result, Rain will develop over parts of the Pacific Northwest into the Northern Rockies on Monday evening. By Tuesday, rain and rain/wet snow will be mostly over parts of the Northern Rockies/Northern High Plains. Elsewhere, a weak front and easterly flow off the Atlantic will allow showers and thunderstorms to develop over parts of southeastern Florida through Tuesday. Ziegenfelder Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php