514 FXUS21 KWNC 171817 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EDT March 17 2026 SYNOPSIS: Dynamical models are in better agreement compared to yesterday indicating amplified mid-level high pressure lingering from the end of week-1 into the beginning of week-2 across the south-central and southwestern CONUS. This pattern supports increased risk (moderate) and a slightly larger area of much above normal temperatures including the Desert Southwest and Southern Plains in the updated outlook. Anticipated surface low development over the Great Plains, shifting eastward leads to enhanced likelihood of high winds across these regions. Strong onshore flow to the Pacific Northwest may increase the possibility of heavy snowfall to the Cascades in Washington and the Olympic Peninsula at the start of week-2. For Alaska, mid-level low pressure is predicted for the Southeast, supporting below-normal temperatures, but such temperatures are not anticipated to reach hazardous criteria at this time. HAZARDS Moderate risk of much above-normal temperatures for the Desert Southwest and Southern Plains, Wed-Thu, Mar 25-26. Slight risk of much above-normal temperatures for the Desert Southwest and Southern Plains, Wed-Fri, Mar 25-27. Moderate risk of high winds for the Northern and Central Plains, Wed-Thu, Mar 25-26. Slight risk of high winds for the Great Plains, Wed-Fri, Mar 25-27. Slight risk of high winds across parts of the East, Thu-Fri, Mar 26-27. Slight risk of heavy snow for the Cascades in Washington and the Olympic Peninsula, Wed-Thu, Mar 25-26. DETAILED SUMMARY FOR FRIDAY MARCH 20 - TUESDAY MARCH 24: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR WEDNESDAY MARCH 25 - TUESDAY MARCH 31: There is better agreement among multiple ensemble means indicating mid-level ridging lingering from the end of week-1 into early week-2 across the southwestern and south-central CONUS, compared to yesterday. Additionally, there are greater 500 hPa positive height departures indicated for the Southern Plains. This translates to increased warm signals for the southwestern and south-central CONUS. Therefore a moderate risk of much above normal temperatures has been designated for the Desert Southwest and Southern Plains, Mar 25-26, where the ECENS (GEFS) Probabilistic Extremes Tool (PET) shows at least a 50-60% (40-50%) chance of maximum temperatures exceeding the 90th percentile, climatologically, and 90 deg F. The National Blend of Models shows near record breaking temperatures for a much wider spread area compared to yesterday, with some areas in the risk area reaching the high 90s to 100 deg F across the Desert Southwest. Temperatures are generally anticipated to be lower than week-1 where temperatures across the Desert Southwest could reach 105 deg F or greater. Temperatures are anticipated to moderate later in week-2, with decreasing positive mid-level height anomalies. Multiple models indicate mid-level troughing forming over the central CONUS moving eastward to the East early in the period. This pattern supports lee cyclogenesis east of the Rockies, with mean surface low activity tracking northeastward to the Northeast. With adjacent surface high pressure over the East, there is increased potential for high winds in the lee of the Rockies. A moderate risk of high winds is designated for the Northern and Central Plains, Mar 25-26, and a broader area of slight risk for the Great Plains, Mar 25-26. The ECENS (GEFS) PET indicates at least a 40-50% (20%) chance of wind speeds exceeding the 85th percentile compared to normal, with uncalibrated ensembles showing at least a 50% chance of wind speeds exceeding 20 mph. Gusty winds combined with warm temperatures and dry fuels may support enhanced risk of wildfires across parts of the Southern and Central Plains. Another broad slight risk area of high winds is also highlighted for the Ohio and Tennessee Valley, Mid-Atlantic and northeastern CONUS, Mar 26-27 associated with the surface low tracking and associated fronts across the region. Enhanced precipitation is possible across parts of the East, although accumulated totals are not anticipated to reach hazards criteria. However, thunderstorms would still be possible for the Great Plains and Midwest. Surface low formation over the Gulf of Alaska is not anticipated to be as strong as indicated yesterday in the models. Therefore, the risk of high winds for southern Alaska is not included in todays outlook. A series of surface lows and fronts including one extending from the end of week-1 into the start of week-2 could bring periods of enhanced rainfall to Hawaii. Above-normal precipitation is predicted for the state in the CPC Week-2 Precipitation Outlook. FORECASTER: Melissa Ou $$