Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 357 PM EDT Tue Apr 13 2021 Valid 00Z Wed Apr 14 2021 - 00Z Fri Apr 16 2021 ...A slow-moving storm will bring widespread snows to the Great Basin and Central Rockies, with heavy accumulations for the mountains... ...There is a Slight Risk of severe thunderstorms over parts of the Central Gulf Coast and Southern Plains, Slight Risk of excessive rainfall over parts of the Central Gulf Coast... ...Critical Fire Weather conditions are expected across portions of the Southwest, Great Basin, and Southern Rockies... A slow-moving area of low pressure over the Upper Mississippi Valley will move eastward to the Lower Great Lakes by Thursday evening. The system will produce widespread precipitation across the Northern Plains and Upper Midwest, including some late-season accumulating snows from Montana to the Upper Peninsula of Michigan. Precipitation is expected to continue into Wednesday before diminishing west to east across the Plains as the system inches eastward. As the system moves east, scattered rain will begin to develop across the Mid-Atlantic and Northeast on Wednesday, continuing into Thursday. An associated quasi-stationary front over the Gulf Coast States will interact with increasing moisture, producing showers and thunderstorms across the Southern Plains and Lower Mississippi Valley on Tuesday evening into Wednesday. The SPC has issued a Slight Risk of severe thunderstorms over parts of the Central Gulf Coast and Southern Plains through Wednesday morning. The main hazards with these storms are frequent lightning, severe thunderstorm wind gust, hail, and an isolated tornado through Wednesday morning. Additionally, these storms will produce heavy rain. The WPC has issued a Slight Risk of excessive rainfall associated with these storms. The main flash flood threat will be mainly localized over urban areas, roads, and small streams. As the Midwest's lead system drifts east, another slow-moving upper-level low over the Pacific Northwest will sink slowly southeastward into the Central Rockies by Thursday. The system will produce higher elevation snow and valley rain across the Great Basin and Rockies through Thursday evening. In contrast to the wet conditions along the Central Gulf Coast into the Lower Mississippi Valley, dry conditions, low relative humidity, and gusty winds will support an Elevated to Critical Fire Weather Threat over the Southwest Tuesday evening into Wednesday. Red Flag Warnings are in effect on Tuesday for a significant portion of the California deserts, southern Nevada, northwestern Arizona, and southern Utah. Ziegenfelder Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php