317 FXUS21 KWNC 251825 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EDT March 25 2026 SYNOPSIS: A pattern change is forecast over the West next week as mid-level low pressure near the West Coast progresses eastward. Much cooler temperatures with high-elevation snow is expected over parts of the western contiguous U.S. (CONUS). Meanwhile, at least one surface low pressure system is likely to develop across the High Plains, bringing associated high wind, blowing dust, and wildfire risks to a large part of the central and western CONUS. Along a wavering frontal boundary south of the possible surface low pressure system, periodic thunderstorms with locally heavy rain are possible across a large part of the central and interior eastern CONUS through the entire first week of April. HAZARDS Moderate risk of high winds for the southern Rockies, southern and central High Plains, and central Great Plains, Thu-Sat, Apr 2-4. Slight risk of high winds for much of the western and central CONUS, Thu-Sun, Apr 2-5. Slight risk of heavy snow for the northern and central Sierra Nevada Mountains, Thu, Apr 2. Slight risk of heavy precipitation from much of the Great Plains to the Appalachians and central Gulf Coast, Thu-Wed, Apr 2-8. DETAILED SUMMARY FOR SATURDAY MARCH 28 - WEDNESDAY APRIL 01: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR THURSDAY APRIL 02 - WEDNESDAY APRIL 08: At the start of week-2, the GEFS and ECENS ensemble means continue to depict a fairly amplified 500-hPa trough along or just inland from the West Coast. This is a slight eastward shift compared to yesterday. During the period, this shortwave is anticipated to progress eastward and weaken as it heads toward a persistent mid-level ridge over or near the eastern CONUS. In its wake, mid-level troughing is expected to re-develop over the western CONUS, although there is significant uncertainty regarding the timing and strength of this feature. The ensemble mean solutions depict daily 500-hPa height anomalies more than 60 meters below normal over much of the western CONUS, with the CMCE and ECENS indicating anomalies of -120 to -150 meters over some portions of the Far West. Following the March heat wave, this longwave pattern change will usher sharply colder temperatures and potentially significant precipitation into parts of the West. A slight risk of heavy snow is posted for the northern and central Sierra Nevada for the first day of the period (April 2) before the mid-level trough pushes east of the region. Although accumulating snow is also expected across the southern Sierra Nevada and the higher elevations of the Great Basin and Central Rockies, models show less support for heavy amounts, so no other areas of heavy snow hazards are posted at this time. As the amplified 500-hPa trough moves eastward and northeastward, leeside cyclogenesis is likely across the High Plains. Deterministic models and their ensemble members are converging on surface low development either over eastern Colorado or Wyoming. The ensemble means are slightly stronger with this system than yesterday, although there is less agreement on timing. Still, a majority of GEFS and ECENS members show this surface low deepening to 996-hPa or lower early in the period. Given good model agreement early week-2 on this evolving surface and longwave 500-hPa pattern, along with springtime climatology, a moderate risk of high winds for April 2-4 is posted across parts of the southern Rockies, much of the central and southern High Plains, and the central Great Plains, with a larger slight risk area covering much of the western and central CONUS through April 5 due to less robust model support for high winds and increasing uncertainty on the evolution of the mid-level and surface weather pattern beyond the middle of week-2. In addition, antecedent conditions are likely to be unseasonably warm weather during the final week of March, which will continue the ongoing trend of declining surface moisture across the central and western CONUS. The combination of the anticipated gusty winds with dry surface growth will likely result in high wildfire danger through much of this region at least into the middle of week-2, particularly in areas not affected by heavy rainfall. The expected mid-level trough in the West may create enough instability to induce dry thunderstorms over the parts of the West, which could serve as a trigger for fire development. Farther east, the Morrill wildfire in southwestern Nebraska recently became the largest in state history, consuming more than 600,000 acres. More than 129,000 additional acres burned in the Cottonwood fire near central Nebraska. The year-to-date total over the central and western CONUS is approaching one million acres, compared to the 10-year average of about 650,000 acres across the entire CONUS. The surface low over the Great Plains is expected to track northeastward through the Great Lakes as the mid-level trough pushes northeastward toward the northern side of a persistent mid-level ridge across the eastern CONUS. A trailing front is expected to push eastward across the Great Plains and into the interior eastern CONUS early in the period, potentially accompanied by heavy rainfall. Thereafter, the evolution of surface conditions over this region is unclear due to increasing model spread, but it seems likely that a weaker mid-level trough will form across the western CONUS as a potent mid-level ridge pushes into the northeastern North Pacific. A preponderance of the models indicate at least the potential for surface pressures over the Great Plains to begin dropping again, resulting in a slow-moving frontal complex which would serve as a focus for the potential of additional heavy precipitation. In any case, high surface pressure centered off the Southeast coast is expected to keep a persistent southerly flow of moist air from the Gulf into portions of the central and interior eastern CONUS, making abundant moisture available for any mechanism that could trigger shower and thunderstorm activity. This set-up raises the possibility of several rounds of heavy precipitation to continue impacting parts of this large region throughout week-2, which supports posting a slight risk of heavy rain that continues throughout the period. There is large model spread, and therefore significant uncertainty, regarding the timing, location, and intensity of any precipitation that does develop, which precludes posting any moderate risk at this time. Still, the potential is there for periods of very heavy precipitation at times across this entire region. The GEFS and ECENS agree that weak 500-hPa troughing moving eastward initially over eastern Mainland Alaska in concert with the western CONUS trough, could support rising mid-level heights as 500-hPa ridging encroaches on the state. No hazardous weather is anticipated during week-2 although mean temperatures are expected to be below normal in southeastern Alaska, and above-normal precipitation is slightly favored across central and southern parts of the state. Multiple Kona Lows brought flooding rainfall to Hawaii during mid-March. The outlook shows somewhat increased chances of above-normal precipitation through at least part of the first week of April, but this is in association with a wetter-than-normal trade wind regime as opposed to additional intense amounts which can be triggered by the Kona Lows. FORECASTER: Rich Tinker $$