028 FXUS21 KWNC 141909 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EST January 14 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 anomalously cold winter temperatures along the northern tier of the CONUS, and high wind and high elevation snow over the Interior West. Surface low development in the lee of the Rockies may potentially trigger heavy precipitation and low elevation heavy snowfall across portions of the Midwest 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 northern portions of the Northern Plains, Upper Mississippi Valley, and western Great Lakes, Sat-Mon, Jan 24-26. Slight risk of much below normal temperatures for portions of the Northern Intermountain, Northern Rockies, Northern Plains, Upper Mississippi Valley, Great Lakes, and Northeast, Thu-Wed, Jan 22-28. Slight risk of heavy snow for portions of the Great Lakes and Central Appalachians, Thu-Wed, Jan 22-28. Slight risk of heavy snow for the higher elevations of the Northern Intermountain, Great Basin and Rockies, Thu-Mon, Jan 22-26 Slight risk of high winds for much of the Interior West, Thu-Mon, Jan 22-26. Moderate risk of heavy precipitation for portions of the Middle and Lower Mississippi, Ohio and Tennessee Valleys, and Southern Appalachians, Fri-Sat, Jan 23-24. Slight risk of heavy precipitation for parts of the Mississippi, Ohio, and Tennessee Valleys, Appalachians, and Southeast, Thu-Sun, Jan 22-25. Slight risk of heavy snow for portions of the Central and Northern Plains, Middle and Upper Mississippi and Ohio Valleys, and western Great Lakes, Thu-Sun, Jan 22-25. DETAILED SUMMARY FOR SATURDAY JANUARY 17 - WEDNESDAY JANUARY 21: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR THURSDAY JANUARY 22 - WEDNESDAY JANUARY 28: The week-2 hazards perspective largely remains on track, though dynamical model 500-hPa height forecasts feature a more transient pattern since yesterday. By the middle of next week, a deep 500-hPa trough over the the eastern U.S. remains favored to deamplify and lift out over the Northeast, followed by a retrogression of the mean negative height departures over south-central Canada, allowing for anomalous troughing (ridging) to overspread much of the Interior West (southeastern U.S.) through mid week-2. However, this pattern looks to be short-lived, as extended range GEFS and ECMWF ensemble solutions progress the mean troughing back over the northeastern CONUS, with rising mid-level heights reemerging across much of the West later in January. With a strong 500-hPa ridge anticipated to remain established over the north Pacific and and Bering Sea during week-2, the general pattern evolution looks to be favorable for the advection of Arctic air over north-central CONUS, at least initially during the period, before much of the anomalous cold shifts eastward with later in week-2. Moreover, a period with mean troughing over the Interior West remains favorable for the ejection of shortwave disturbances downstream, where predicted surface low development in the lee of the Rockies continues to support an increased risk of heavy precipitation and snowfall over parts of the Great Plains, Mississippi, Tennessee and Ohio Valleys. With a 500-hPa trough weakening over the eastern U.S. next week, the slight risk of much below normal temperatures is discontinued over the northeastern CONUS as the coldest temperatures look to have timed off into late week-1 based on raw temperature tools. As the mean mid-level troughing expands westward, an area of strong mean surface high pressure is favored to descend southward from the Canadian Prairies, with the latest ensembles favoring more of a southward and eastward expansion of this surface feature relative to yesterday. Probabilistic Extreme Tools (PET) guidance maintains at least 20% chances of minimum temperatures falling below the 15th climatological percentile over the northern tier of the CONUS, with the strongest signals (>30% chances) over the north-central CONUS by mid week-2. Discrepancies continue to exist in the overall strength of the cold signals between the GEFS and ECMWF PET (with the latter remaining more robust), however uncalibrated wind chill guidance shows 30-40% chances for values falling below -40 deg F, supporting the addition of a moderate risk of much below normal temperatures for Jan 24-26. Surrounding this area, a slight risk of much below normal temperatures remains issued, valid for all of week-2, and is nudged southward across the Central Plains and Middle Mississippi Valley. Consideration was given to include portions of the Southern Plains based surface high pressure in the ECMWF ensemble reaching as far south as the Texas and Oklahoma Panhandle, however predicted negative temperature anomalies in the tools are not quite as cold. The slight risk area is also expanded eastward to include portions of the New England where there is increased support in the PETs likely tied to the mean mid-level troughing returning later in the period. The potential for multiple shots of cold air over the northern tier of the CONUS also favors a combination of pure lake effect snow and lake enhanced snow over the Great Lakes, thus a slight risk of heavy snow remains posted downwind of the Lakes and into the Central Appalachians for all of week-2. 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 day 12 (Jan 26) before heights begin the 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. Precipitation based PETs also show increased signals for 3-day amounts exceeding the 85th percentile over portions of southern California and the Desert Southwest early in week-2. However, uncalibrated tools are comparably drier with this potential resulting in no corresponding hazards being issued at this time The transition towards more mid-level troughing (ridging) the western (eastern) CONUS also supports surface low development in the lee of Rockies with moist return flow from the Gulf of Mexico increasing the likelihood of heavy precipitation. One or more surface lows are favored through the middle of the period, though the details of timing and storm track(s) remain unclear based on the daily mean ensemble guidance. However, there continues to be good model agreement in daily precipitation tools showing the greatest precipitation threat over portions of the Tennessee and Ohio Valleys on days 9 and 10 (Jan 23-24). While PETs are still supportive of a slight risk designation, deference is given to the more recently skillful raw precipitation tools over this part of the country Therefore, a moderate risk of heavy precipitation remains posted (Jan 23-24) for these areas and is slightly expanded southward in the updated outlook where both the GEFS and ECMWF indicate >40% chances for 3-day amounts exceeding an inch. Within this moderate risk area, localized flash or small stream flooding is possible during the period. A broader slight risk area remains posted for Jan 22-25, where PETs depict 20-30% chances for 3-day amounts exceeding the 85th percentile and 1 inch. With the aforementioned anomalous cold air expected to intrude over the northern tier of the CONUS, the enhanced moisture is expected to be conducive for accumulating snowfall on the backside of any low pressure system. Although uncalibrated probabilities for amounts exceeding 4 inches are low in the ECMWF and GEFS ensembles, a slight risk of heavy snow is posted from the Central and Northern high Plains extending eastward to the Great Lakes based on the predicted baroclinicity in the region and deterministic solutions. No hazards are issued over Alaska. There is better agreement between the ECMWF and GEFS in regards to strong ridging over the north Pacific with a ridge axis extending northward across the Mainland. This pattern 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. With persistent troughing favored underneath strong ridging forecast over the northern Pacific, one or more Kona lows may develop and impact parts of Hawaii during week-2. There is considerable uncertainty regarding the location, evolution, and magnitude of any hazardous conditions, but there is general agreement that precipitation over most of the state will be above normal for week-2. Potential impacts include periods of heavy precipitation, high winds, and significant waves. FORECASTER: Nick Novella $$