424 FXUS21 KWNC 081752 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EDT October 08 2026 SYNOPSIS: Mid-level low pressure is likely to promote chilly northeasterly flow, supporting an increased risk of much below temperatures and first fall freezes over the northeastern contiguous U.S. (CONUS). Surface low development over the upper Midwest and an accompanying frontal boundary extending southward increases the risk of heavy precipitation across the Southern Plains and Lower Mississippi Valley. Favored low pressure at the surface and mid-levels over Alaska supports an increased risk of high winds and heavy precipitation early in the period early in week-2. HAZARDS Slight risk of much below normal temperatures for much of the Northeast, Fri, Oct 16. Slight risk of heavy precipitation for parts of the Southern Plains, and Lower Mississippi Valley, Fri-Sat, Oct 16-17. Slight risk of high winds across the Aleutians, Alaska Peninsula, and coastal portions of southwestern, south-central, and southeastern Alaska, Fri-Sat, Oct 16-17. Slight risk of heavy precipitation for parts of south-central and southeastern Alaska, Fri-Sat, Oct 16-17. DETAILED SUMMARY FOR SUNDAY OCTOBER 11 - THURSDAY OCTOBER 15: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR FRIDAY OCTOBER 16 - THURSDAY OCTOBER 22: Late in week-1, ensemble mean solutions from the ECENS and the GEFS have come into better agreement in regards to the strength and shape of a 500-hPa trough lifting out over the northeastern CONUS. By the start of week-2, another 500-hPa trough remains favored upstream in the lee of the Rockies, where models are unanimous in featuring a developing mean surface low traversing the upper Midwest, with an elongated mean frontal boundary extending well into the Southern Plains and Mississippi Valley late next week. As the shortwave disturbance propagates eastward into the following weekend, residual cyclonic flow is expected to remain established across southwestern CONUS underneath an amplified ridge center to the north. The placement and timing of these mid-level features looks to contribute to a favorable environment for enhanced and possibly heavy precipitation along the mean frontal boundary, before an anomalously cooler and drier air mass descends from the Canadian Prairies and overspreads much of the CONUS east of the Rockies later in week-2. Meanwhile over Alaska, amplified mid-level troughing remains favored over the Bering Strait and the western Mainland late in week-1, where better agreement exists between the GEFS and ECENS favoring more zonal flow by the middle of the period to quell any wind and precipitation related hazards. While temperatures are expected to moderate with 500-hPa troughing favored to lift out over the Canadian Maritimes and Northeast later next week, a slight risk of much below normal temperatures remains posted for Oct 16 based on both raw and calibrated temperatures tools depicting increased chances for minimum temperatures falling below the 15th percentile and below freezing. Climatologically, first fall freezes generally occur between late September through mid-October for this part of the country, though any temperatures dipping to near freezing levels may still trigger cold temperature advisories for areas that have not experienced their first frost and/or freezes early in the period. Tied to the troughing upstream over the upper Midwest, both the GEFS and ECENS favor a stronger mean surface high behind the mean frontal boundary compared to yesterday. A corresponding uptick in cold signals is also evident in the Probabilistic Extremes Tools (PETs), which depict a larger coverage of at least 20% chances for minimum temperatures falling below the 15th percentile along the frontal boundary from the Southern Plains to the Great Lakes early in the period. With the coldest temperatures likely further north across the Northern Plains and Upper Midwest, any risk of subfreezing temperatures are expected to be transient, as mid-level heights begin to rapidly rise across the part of the county. As a result, no corresponding temperature hazards are posted. With enhanced atmospheric moisture favored ahead of the mean frontal boundary, a slight risk of heavy precipitation remains posted based on continued support in the precipitation guidance. A drier mean solution is seen in the GEFS early in the period compared to yesterday, which is notable and somewhat surprising considering the stronger frontal forcing being favored. However, there is better support in the Canadian that well aligns with the ECMWF and focuses this heavy precipitation over the Southern Plains and Lower Mississippi Valley. As a result, the slight risk coverage is adjusted to exclude portions of the Middle Mississippi, Ohio and Tennessee Valleys, and remains valid through Oct 17 before drier air overspreads the highlighted area. Due to drier conditions expected further east, the flood possible hazard is removed over the eastern and central portions of the Gulf Coast region. However, localized flooding cannot be ruled out as any additional rainfall could worsen saturated ground conditions expected in the wake of Hurricane Isaias that is likely to impact the region based on the latest National Hurricane Center official track forecasts during week-1. Amplified 500-hPa troughing is favored over the Bering Sea late in week-1. Although this mid-level feature is expected to deamplify, there continues to be tool support for an increased risk of episodes of high winds and heavy precipitation associated with mean surface low situated in the Gulf of Alaska. However, due to more zonal mid-level flow expected with diminished signals in both the wind and precipitation based PETS compared to yesterday, only slight risks of heavy precipitation and high winds are issued for early week-2, and the moderate risk of high winds is discontinued in the updated outlook. FORECASTER: Nick Novella $$