630 FXUS01 KWBC 050736 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 335 AM EDT Tue May 05 2026 Valid 12Z Tue May 05 2026 - 12Z Thu May 07 2026 ...Significant winter weather set to continue in the Rockies through midweek... ...Severe weather and heavy rain to impact the Southern Plains and Lower Mississippi Valley through midweek, before approaching the Southeast.. ...Chilly temperatures will persist across the Central and Eastern U.S. after the frontal passage, while the Northwest begins to moderate... In the Rockies, a significant winter storm has begun and is expected to bring heavy snow through Wednesday evening. Impacts will be greatest in the mountains, especially in Colorado and Wyoming, where there is over a 90% chance of at least minor winter weather impacts and a medium chance (40-60%) of major impacts, per the Probabilistic Winter Storm Severity Index (WSSI-P). The bulk of snowfall and travel-related impacts are expected to occur Tuesday night into Wednesday. Accumulations of 1 to 2 feet of snow are expected across the northern mountains and foothills. This will result in significant travel impacts, damaged tree limbs from heavy snow, and localized power outages. As a result, Winter Storm Warnings and Advisories are in effect until Wednesday afternoon. Elsewhere, a strong cold front will continue moving through the Central Plains, reaching the Southern Plains and Southeast by the middle of the week. A potent upper-level cutoff low in the Southwest will amalgamate with a broader upper-level trough encompassing much of the Plains and Midwest. As a result, widespread showers and thunderstorms are expected throughout much of the country. Beginning this morning, showers and thunderstorms are expected throughout portions of the Central Plains, Mississippi and Ohio Valleys, and the Northeast. As the front continues southward through the evening, showers and thunderstorms are expected to begin in parts of the Southeast and Tennessee Valley. Concurrently, a dryline has set up in the Southern Plains. Thunderstorms today will have the potential to be strong to severe beginning in the afternoon. Given strong deep-layer wind shear and moderate instability, the most dominant risks will be large hail and strong winds, though there remains a possibility of tornadoes. As such, the Storm Prediction Center (SPC) has issued a Slight Risk (level 2/5) of severe weather for a majority of the Lower Mississippi Valley. Simultaneously, given the large extent of the front, showers and thunderstorms will also develop across parts of the Midwest, Great Lakes, Mid-Atlantic, and Northeast. Portions of the Northeast, in particular, may also be at risk of severe weather, and the SPC has issued a Marginal Risk (level 1/5) of severe weather, contingent on forecast instability remaining unchanged. On Wednesday, the focus shifts slightly farther south as the front continues slowly toward the Gulf. At this point, the front will be oriented from the Mid-Atlantic to the Southern Plains. Widespread showers and thunderstorms will develop in the vicinity of the front on Wednesday and through the evening hours. Similarly to today, the strongest storms with a renewed severe potential will occur throughout the Lower Mississippi Valley and Southern Plains, with the core farther south than today. Hazards associated with thunderstorms include large hail, strong gusty winds, and the possibility of tornadoes. Therefore, the SPC has issued a Slight Risk (level 2/5) of severe weather for this region on Wednesday. Additionally, thunderstorms will have the potential for heavy rainfall as rich moisture flows in from the Gulf. Localized/isolated instances of flash flooding are possible with these storms, particularly in parts of the Lower Tennessee Valley and the Southeast. As such, there is also a Slight Risk (level 2/4) of excessive rainfall for these areas on Wednesday. Thunderstorms are expected to continue further south on Thursday as the front moves further into the Southeast. Uncertainty remains on the exact positioning of the front on Thursday, but showers and thunderstorms are expected across much of the Southeast. Meanwhile, the previously mentioned upper-level cutoff low off the coast of California, along with several surface troughs and a weakening surface low-pressure system, will continue to bring precipitation to parts of northern California and the Central Great Basin today. Precipitation is expected to remain in the form of rain and thunderstorms along the coast and low elevations, with snow and a wintry mix in the high-elevation regions, specifically the Sierra Nevada. An end to precipitation in this region is expected by Wednesday as the system moves eastward toward the Rockies. Temperatures will remain significantly below average across the northern and eastern portions of the country following the cold front's passage. Highs in parts of the Central Rockies may struggle to leave the 40s on Tuesday. High-elevation areas, especially those being impacted by the winter storm, could dip as low as 30 degrees below average, with temperatures hovering in the 30s. Conversely, while the Pacific Northwest will finally begin to see a slow moderation in heat, unseasonably warm temperatures in the 80s remain possible through the middle of the week. Blanco-Alcala Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$