664 FXUS21 KWNC 101902 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EST January 10 2026 SYNOPSIS: Mid-level low pressure developing over the eastern CONUS brings increased chances for much below normal temperatures, snow, and wind to the region. Across the West, mid-level high pressure is forecast with associated surface high pressure over the Great Basin. This increases chances for high winds across parts of southern California. By the second half of the period, there is increased uncertainty across much of the country with a rapidly evolving pattern. There continues to be increased potential for Kona lows bringing enhanced precipitation and periodic high wind gusts to parts of Hawaii, although there is significant uncertainty regarding the details of this potential. HAZARDS Slight risk of high winds for parts of Southern California, Sun-Mon, Jan 18-19. Slight risk of high winds in portions of the Appalachians, Northeast, and Mid-Atlantic, Sun-Tue, Jan 18-20. Slight risk of heavy snow for the northern Mid-Atlantic, Northeast, Appalachians, Great Lakes, Sun-Tue, Jan 18-20. Slight risk of much below normal temperatures for the Upper Mississippi Valley and western Great Lakes, Sun-Mon, Jan 18-19. Slight risk of much below normal temperatures for portions of the Gulf Coast and Florida, Sun-Tue, Jan 18-20. Slight risk of much below normal temperatures for portions of the Northeast, Mon-Fri, Jan 19-24. DETAILED SUMMARY FOR TUESDAY JANUARY 13 - SATURDAY JANUARY 17: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR SUNDAY JANUARY 18 - SATURDAY JANUARY 24: There is good model agreement across multiple model ensemble means during week-2 indicating an amplified and progressive mid-level height pattern. At the onset of the period, mid-level ridging is forecast over the Northeast Pacific and western CONUS and troughing over the eastern CONUS. By the middle of week-2, mid-level ridging is forecast to progress eastward, eventually building over the southeastern CONUS by the end of the week. Near to below-normal heights are then favored to develop over the interior West. In Alaska, mid-level ridging is forecast to be near southwest Alaska. There are disagreements among the tools regarding the placement of the ridge which could have large impacts on temperatures in the state. The surface pattern of high pressure over the interior West with inverted surface troughing along the West Coast could result in a tight pressure gradient across parts of the southwestern CONUS and a favorable setup for Santa Ana wind episodes for southern coastal California at the beginning of week-2. A slight risk of high winds continues in southern California, Jan 18-19, primarily based on pattern recognition and recent deterministic guidance. The Probabilistic Extremes Tools (PETs) have decreased its signal for high winds significantly for this region. Fortunately, the recent wetness there should reduce wildfire potential. Across the East, multiple models continue to show the potential for at least one or more Alberta Clipper type systems along with surface lows tracking along the East Coast. These series of lows and associated fronts support increased likelihood of enhanced winds and snowfall for parts of the eastern CONUS, although there is considerable uncertainty regarding the specifics of the timing, location, and evolution of these features and associated impacts. The slight risk of high winds includes parts of the Mid-Atlantic, the Appalachians and Northeast, valid Jan 18-20. The GEFS and ECENS PETs indicate at least a 20% chance of wind speeds exceeding the 85th percentile and 20 mph. Based on increasing signals for heavy snow in model guidance, the slight risk of heavy snow (Jan 18-20) includes the Southern Appalachians and northern Mid-Atlantic as well as the Northeast, Central Appalachians, and Great Lakes. The GEFS Snow Water Equivalent (SWE) PET now indicates at least a 20% chance of 3-day SWE totals exceeding the 85th percentile in the highlighted risk area. Many of the recent deterministic and ensemble guidance runs indicate an increased chance for snow into the major metropolitan regions along the East Coast. There is a very large amount of uncertainty regarding this potential but in light of the most recent runs, the slight risk of heavy snow has been extended to near interstate 95 from Richmond northwards. In the wake of these systems, colder air is forecast to build across parts of the eastern CONUS early in week-2. Apparent temperatures may approach hazardous criteria although at this time model guidance remains less robust than the mid-level height pattern would otherwise suggest. Slight risk of much below normal temperatures is initially designated for the Upper Mississippi Valley and western Great Lakes (Jan 18-19) and the Gulf Coast (Jan 18-20), shifting to the Northeast, Jan 19-24. Multiple model PETs are in fairly good agreement indicating at least a 20% chance of minimum temperatures falling to the lowest 15th percentile climatologically and -10 deg F (wind chills below -20 deg F) across the northern hazard areas, and freezing to subfreezing temperatures across the Gulf Coast. There are significant model differences in the GEFS and ECENS in terms of the synoptic pattern in Alaska. The ECENS favors mid-level troughing across much of the interior of the state, whereas the GEFS maintains mid-level ridging. The ECENS solution would favor a much colder pattern than the GEFS for week-2. Due to significant differences no associated hazards are specified for Alaska at this time. A series of Kona lows may 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: Ryan Bolt $$