Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 346 PM EDT Fri Mar 15 2024 Valid 00Z Sat Mar 16 2024 - 00Z Mon Mar 18 2024 ...Heavy mountain snow expands across Four Corners and Southern Rockies this weekend... ...Severe Thunderstorm and Excessive Rainfall chances shift south into the Southeast and Gulf Coast States... ...Mild weather continues across the Pacific Northwest and East Coast... A closed upper low will continue spinning over the Southwest this weekend, while an upper ridge builds over the Northwest and a deep trough descends into the Great Lakes/Midwest. Shortwave energy will round the base of the closed low in the Southwest and accelerate through Texas and the Gulf Coast leading to heightened Severe Weather and Excessive Rainfall threats this weekend. At the surface, a slow moving cold front will eventually stall out along the Gulf Coast and be the focus for thunderstorms and heavy rainfall. Tonight, scattered to isolated thunderstorms (some severe) will develop along the cold front extending from the Edwards Plateau into south-central Texas. An Enhanced Risk (level 3/5) of Severe Thunderstorms is in effect for those areas tonight, while a Slight Risk (level 2/5) extends from there out across the central Gulf Coast and into the Florida panhandle, where very large hail and isolated damaging winds are expected. In addition to that, a Slight Risk of Excessive Rainfall (at least 15%) is in effect for those same areas where 3-4 inches of rainfall may accumulate. The Slight Severe Weather and Excessive Rainfall Risks continue over southern Texas on Saturday where the cold front will stall out. Scattered showers and thunderstorms will continue across the central Gulf Coast as well. While heavy snow diminishes later today across the central Rockies, heavy snow will expand and intensify across the Four Corners this weekend and is likely to redevelop over the Southern Rockies on Sunday. For the higher elevations of the Southwest and Four Corners region, including portions of the Mogollon Rim north into the southern Wasatch and the San Juans, snow probabilities for amounts of at least 12 inches are moderate to high (50-90%). Localized totals up to 2 feet are possible. By Sunday, the heaviest snowfall is expected to transition to the Sangre de Cristo and Jemez Mountains. Heavy snow rates of up to 2"/hr and gusty winds exceeding 35mph (locally higher to 50mph) will cause blowing snow and reduced visibility, especially across the mountain roads and passes. This will create difficult to at times impossible travel, with road closures likely. Disruptions to infrastructure due to power outages are possible as well. Elsewhere, an upper ridge will promote increasing heights and above average temperatures for the Northwest this weekend. High temperatures in the 60s and 70s will be 15-25 degrees above average for this time of year. Meanwhile, a deep upper level trough will supply ample southerly flow into the East Coast through Sunday after which a cold front will sweep through and return temperatures to seasonal averages. This weekend though, highs should be 5-15 degrees above average up and down the coast. Kebede Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php