293 FXUS21 KWNC 171923 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EST January 17 2026 SYNOPSIS: A developing area of mid-level low pressure over south-central Canada and the western contiguous U.S. (CONUS) increases the risk of multiple weather related hazards including heavy precipitation and snow and high winds for portions of the Pacific Northwest, anomalously cold winter temperatures along the northern tier of the CONUS, and high wind and high elevation snow over the Interior West. Surface low pressure over the Canadian Maritimes may potentially trigger heavy snowfall across portions of the Great Lakes and Northeast U.S. during the period. In the central Pacific, there is an increased chance of Kona low development potentially impacting parts of Hawaii, with enhanced precipitation and occasional high wind gusts HAZARDS Moderate risk of much below normal temperatures for portions of the Central and Northern Plains, Middle and Upper Mississippi Valley, and western Great Lakes, Sun-Mon, Jan 25-26. Slight risk of much below normal temperatures for much of the central and eastern CONUS, Sun-Wed, Jan 25-28. Slight risk of heavy snow for portions of the Great Lakes and Northeast U.S., Sun-Tue, Jan 25-27. Slight risk of heavy snow for the Northern Rockies, Sun-Thu, Jan 25-29. Slight risk of heavy snow for the Cascade Mountains, Sun-Thu, Jan 25-29. Slight risk of heavy precipitation for much of the Pacific Northwest, Sun-Thu, Jan 25-29. Slight risk of high winds for much of the Pacific Northwest, Interior West and western High Plains, Sun-Thu, Jan 25-29. Slight risk of high winds for all of the Gulf Coast and Eastern Seaboard and nearby inland regions, Sun-Tue, Jan 25-27. DETAILED SUMMARY FOR TUESDAY JANUARY 20 - SATURDAY JANUARY 24: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR SUNDAY JANUARY 25 - SATURDAY JANUARY 31: Model ensembles are in good agreement with the synoptic setup at the outset of week-2, with fairly amplified mid-level ridging over the Bering Sea and Alaska, and a broad trough downstream with negative 500-hPa height anomalies stretching all along the U.S.-Canada border, and weak positive height anomalies over the Southern Tier of the U.S. However, as the forecast period progresses solutions between the GEFS and ECMWF diverge quite a bit with respect to the synoptic evolution over the North Pacific and West Coast, with the GEFS building a stronger ridge centered on the coast, while the ECWMF builds a weaker ridge a bit further to the east. The models are in much better agreement further east, favoring a persistent trough centered over eastern Canada, which paired with the upstream ridge provides a good setup for an incursion of very cold Arctic air into the CONUS east of the Rockies. Over the northern tier of the CONUS, strong mean surface high pressure and accompanying Arctic air is favored to descend southward from the Canadian Prairies early in week-2, but the . Probabilistic Extreme Tools (PETs) from the GEFS and ECMWF have diverged once again with regard to the southern extent of the cold potential, as well as the penetration of the coldest air. The ECMWF indicates >60% chances of minimum temperatures falling below the 15th percentile close to the Canadian border but does not favor hazardous criteria being met much further south than Kansas, while the GEFS extends at least 20% chances as far south as Mexico and the Gulf Coast. Despite this large discrepancy, pattern recognition of the predicted synoptic pattern would tend to favor the GEFS solution pushing colder air further south. A moderate risk of much below normal temperatures remains posted for the Northern Plains and Upper Mississippi Valley and expanded into portions of the Central Plains and Middle Mississippi Valley and further east into the Great Lakes, valid Jan 25-26, while a much broader slight risk of much below normal temperatures covers much of the CONUS east of the Rockies, extending into North Texas, but excluding the remainder of the Southern Plains, the Gulf Coast, and the East Coast up to the Outer Banks. This slight risk is valid Jan 25-28. Model guidance continues to indicate deep surface low pressure over the Canadian Maritimes early in the period, which is favored to interact with the spreading surface high over the countrys midsection and generate enhanced winds along the Southern Tier and up the Eastern Seaboard. This is well indicated by the PETs from both the GEFS and ECMWF, depicting a frontal field of enhanced wind with at least a 20% chance of 3-day maximum wind speed exceeding the 85th percentile and at least 20mph early in week-2, warranting a slight risk of high winds for these regions valid Jan 25-27. Surface winds over the Great Lakes favors potentially heavy lake-effect snow, and model solutions also indicate trailing moisture over the Northeast U.S., with uncalibrated probabilities from the ECMWF and GEFS extending at least a 20% chance of 4 inches of snow accumulation across the Northeast. Therefore, a slight risk of heavy snow is posted for much of the Great Lakes and extending eastward to cover much of Pennsylvania, New Jersey and all of New England. Based on continued agreement among the GEFS, ECMWF, and Canadian ensembles in regards to the development of negative height departures over the Interior West, slight risks of high elevation heavy snow and high winds remain posted for the region, valid through Jan 29 before mid-level heights begin to build across the western CONUS later in week-2. Both the Snow Water Equivalent (SWE) and wind PETs maintain increased chances for values exceeding the 85th percentile through the middle of the period. Across the Pacific Northwest, the ECMWF Integrated Vapor Transport (IVT) tool depicts an increasing Atmospheric River (AR) potential during in week-2 which is supported in the ECMWF PET with at least 20% chances of 3-day amounts exceeding the 85th percentile and 2 inches from northern California to western Washington for much of week-2. The GEFS IVT is beginning to show some more signal, and the GEFS PET is now indicating the potential of meeting hazardous thresholds in the Pacific Northwest. A slight risk of heavy precipitation is posted for much of the Pacific Northwest for Jan 25-29, as well a slight risk of heavy snow for the Cascade Mountains, also for the same period. No hazards are issued over Alaska. The strong ridging over the north Pacific and into the Mainland remains favorable for the above-normal temperatures with a tilt in the odds for above-normal precipitation. Should the mid-level ridge axis remain amplified and shift westward, this would allow for more cross polar flow with colder temperatures developing across the Mainland and any temperature trends will continue to be monitored. FORECASTER: Danny Barandiaran $$