


Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
562 FXUS01 KWBC 120746 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 346 AM EDT Mon May 12 2025 Valid 12Z Mon May 12 2025 - 12Z Wed May 14 2025 ...Thunderstorms and heavy rain from the Southeast to the Mid-Atlantic... ...Showers and storms in the Northwest; seasonally cool in the East and trending cooler in the West... ...Record heat for the Northern and Southern Plains... A meandering storm system over the Lower Mississippi Valley continues to deliver a blend of both Gulf and Atlantic moisture into the Southeast. Today, the shield of rain and embedded thunderstorms will make its way north into the Mid-Atlantic while still producing widespread showers and storms throughout the Southeast. WPC maintains a Slight Risk (threat level 2/4) from Virginia on south through the Carolinas and as far south as southwest Florida. In southeast Florida, a Moderate Risk (threat level 3/4) was introduced due to the expectation of torrential rainfall rates over the highly urbanized metropolitan section of southeast Florida. Locally significant flash flooding is possible in southeast Florida today. A Marginal Risk (threat level 1/4) stretches as far west as the Ozarks and Middle Mississippi Valley where isolated instances of flash flooding are possible. The storm system makes its way through the Ohio and Tennessee Valleys on Tuesday with the axis of heavy rainfall becoming more fixated over the Mid-Atlantic. A Slight Risk remains in place over the Mid-Atlantic while the Marginal Risk extends as far west as the upper Ohio Valley and southern Appalachians. Through early Wednesday morning, the Blue Ridge Mountains of North Carolina and Virginia are likely to see the heaviest rainfall given the southeasterly flow will provide upslope-enhanced rainfall rates over the higher terrain. As much as 3 to 5 inches of rainfall are forecast in the Blue Ridge with localized amounts approaching 7 inches possible. The Virginia Piedmont on south to southeast North Carolina could also receive as much as 2 to 4 inches of rainfall. In the West, an incoming storm system will usher in widespread showers (snow for the higher terrain of the Northern Rockies) and much cooler temperatures over the Pacific Northwest today, then throughout the western third of the CONUS by Tuesday. Ahead of the cold front, blustery winds will be common across the Great Basin, the California Peninsular Range, portions of the Mojave Desert, and as far east as northern Arizona. Wind Advisories were issued for these areas due to wind gusts surpassing 50 mph tomorrow in some areas, making travel potentially difficult some high profile vehicles. By Tuesday, rain and mountain snow will progress east into Utah, Montana, Idaho, and Wyoming. Monday marks the last day of widespread 90s in the Desert Southwest as temperatures will be 10-30 degrees cooler by Tuesday and Wednesday. Farther north, expected widespread 50s and 60s throughout the Great Basin and Northwest through mid-week. Over the Northern Plains, hot and record high temperatures will persist through Tuesday, along with windy/dry conditions throughout the region today. Red flag warnings are in effect through today with Elevated to Critical fire weather conditions still in place. Temperatures will easily reach the 90s with a few areas potentially as high as the century mark from the Dakotas to Minnesota, breaking numerous daily record high temperatures today. Temperatures only back down by a few degrees on Tuesday, resulting in more opportunities for record breaking heat in the Northern Plains. Moderate to Major HeatRisk levels are forecast for this region -- stay hydrated and out of the sun during the hottest part of the day. As the upper level ridge advances over the Heartland the first half of the week, temperatures will continue to heat up throughout the Central and Southern Plains. The hottest conditions will be found deep in the heart of Texas where widespread 100F readings are likely over much of the Lone Star state Tuesday and into Wednesday. Expect record breaking heat across much of central and southern Texas through mid-week. HeatRisk values will increase into the Moderate category by Tuesday, with more widespread cases of Major values showing up in parts of the Rio Grande Valley, central Texas, and eastern Texas. Mullinax Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$