327 FXUS21 KWNC 231810 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EDT March 23 2026 SYNOPSIS: The anomalously strong mid-level high pressure, currently over the West, is forecast to shift eastward to the eastern contiguous U.S. (CONUS) by the end of March. Downstream of a weak area of mid-level low pressure across the western CONUS, multiple low pressure systems with periods of enhanced rainfall are expected to affect the Great Plains, Mississippi Valley, and Midwest during the first week of April. Above-normal precipitation is favored to persist across Hawaii into early April. HAZARDS Slight risk of heavy precipitation for parts of the Great Plains and Mississippi Valley, Tue-Mon, Mar 31-Apr 6. Slight risk of high winds for parts of the western and central U.S., Tue-Mon, Mar 31-Apr 6. DETAILED SUMMARY FOR THURSDAY MARCH 26 - MONDAY MARCH 30: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR TUESDAY MARCH 31 - MONDAY APRIL 06: The GEFS, ECENS, and CMCE are in good agreement that a low-amplitude 500-hPa trough becomes established near or just inland from the West Coast heading into April. At the beginning of week-2, a shortwave trough is forecast to eject eastward from the southwestern CONUS and result in lee cyclogenesis across the High Plains by March 31. This low pressure system and its trailing cold front are then likely to progress eastward to the Mississippi Valley. Although the 24-hour precipitation amounts from the uncalibrated ECENS and GEFS would support a moderate risk for heavy precipitation across southeastern Oklahoma, eastern Texas, and the Lower to Middle Mississippi Valley, their reforecast tools have lower probabilities (< 40% and <30% in the ECENS and GEFS, respectively) for more than 1 inch from March 31 - April 2. It appears that the greatest signal for heavy precipitation for the south-central CONUS is on April 1 and 2 and the addition of a moderate risk may be added to Tuesday's hazards outlook if there is better agreement among the precipitation tools. Another factor in maintaining only a slight risk of heavy precipitation was a relatively low flood risk for early spring due to ongoing drought for that region. Since multi-model ensemble mean solutions depict a persistent 500-hPa trough upstream over the southwestern CONUS along with a continuation of moist, southeasterly surface low, a slight risk of heavy precipitation for the eastern Great Plains, Middle to Lower Mississippi Valley, and Ohio to Tennessee Valleys is valid through the entirety of week-2. Given the time of year with adequate low-level moisture and instability, there is an increased chance of thunderstorms within the designated slight risk of heavy precipitation. Early April climatology and predicted shortwave troughs ejecting from the southwestern CONUS support a slight risk of high winds for the Four Corners region, much of the Great Plains, and parts of the Midwest. Due a large spread among the ECENS and GEFS members on where leeside cyclogenesis occurs along the High Plains (anywhere from eastern Colorado to southeastern Montana), an expansive slight risk of high winds was warranted. Once the longwave 500-hPa trough develops near the West Coast, there could be accumulating snow at the higher elevations of the Sierra Nevada Mountains and even farther inland across the Central Rockies. However, heavy snow is not anticipated at this time. The GEFS and ECENS agree that a broad 500-hPa trough persists over Alaska through early April which would favor above-normal precipitation for southeastern parts of the state. However, precipitation is forecast to remain well below any hazardous thresholds. Multiple Kona Lows brought flooding rainfall to Hawaii during mid-March. Although the week-2 outlook has an increased chance of above-normal precipitation, the ECENS and GEFS favor more of a wetter-than-normal trade wind regime during early April. FORECASTER: Brad Pugh $$