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   FOUS11 KWBC 152000   
   QPFHSD   
      
   Probabilistic Heavy Snow and Icing Discussion   
   NWS Weather Prediction Center College Park MD   
   300 PM EST Sun Feb 15 2026   
      
   Valid 00Z Mon Feb 16 2026 - 00Z Thu Feb 19 2026   
      
      
   ...Cascades & Olympics...   
   Days 2-3...   
      
   On Monday, a strengthening 500mb trough will dig south down the   
   British Columbia coast towards Washington State. The trough will   
   quickly close off into a closed low west of British Columbia. The   
   upper low will continue south down the coast Tuesday, moving off   
   the coast of Washington. Then the low will drift east over the   
   state, as it re-opens up into a trough. With this very complex,   
   rapidly changing, but slow-moving upper level pattern evolution, a   
   prolonged period of active weather is expected into the Pacific   
   Northwest.   
      
   Sharp height falls and excellent 500mb PVA, combined with an   
   influx of 850-300mb mean- layer moisture and upslope enhancement,   
   will produce periods of snow over the Olympics and Cascades. Snow   
   levels will plummet to as low as 600ft around the WA Cascades and   
   Olympics Monday morning, while 3,000ft snow levels in the OR   
   Cascades will be more common. Some of OR's coastal range could see   
   snow to elevations as low as 1,000ft on Tuesday. While these snow   
   levels are getting quite low, snowfall totals below 2,000ft in the   
   WA/OR Cascades will remain fairly light compared to many   
   winter time snow events. The heaviest snowfall is expected above   
   3,000ft where 72-hour WPC probabilities are now into the higher   
   moderate range (50-70%) for additional snowfall totals >4" for   
   both Snoqualmie and Stevens Passes. Given the long duration but   
   lack of heavy hourly rates, WSSI-P shows the chances for Minor   
   Impacts are generally on the low side (20-40%). Impacts are most   
   likely to be a combination of snow covered roads and reduced   
   visibilities.   
      
      
   ...California...   
   Days 2-3...   
      
   ...Multiple days of heavy and disruptive snowfall to affect the   
   California mountain ranges today and continuing into next week...   
      
   A pair of potent Pacific storm systems will work together to direct   
   copious amounts of moisture at the mountain ranges of the "Golden   
   State" beginning today and lasting well into the upcoming week. A   
   broad positively-tilted upper level troughing pattern off the   
   Pacific NW coast will supply low-mid level moisture that allows for   
   light snow through tonight into the higher terrain of the   
   Siskiyou, Shasta, and Salmon Mountains. The heaviest snowfall   
   totals through tonight will be above 5,000ft where 1-2 feet of new   
   snow accumulation are possible at the higher elevations.   
      
   Tonight, an upper-level trough that has thus far been far enough   
   off the coast to keep associated impacts minimal, will approach the   
   coast. Mid- to- upper level heights will fall over CA in response.   
   This will allow for strengthening IVT to direct subtropical   
   moisture at the state. The state will be placed ahead of a 500mb   
   jet streak that will generate excellent upper- level divergence   
   aloft, along with a barrage of Pacific moisture and strong   
   topographically- enhanced snowfall rates.   
      
   Monday marks the beginning of very heavy snowfall along the Sierra   
   Nevada with snow levels initially starting out around 6,000ft,   
   then falling to as low as 3,000ft by Monday night in the northern   
   Sierra, and 4,000 ft for the southern Sierra Nevada. Snowfall rates   
   between 1-2"/hr will be common with some instances of >3"/hr   
   snowfall rates in the central and southern Sierra Nevada. Heavy   
   snow is also expected in the Transverse Ranges above 6,000ft.   
      
   On Tuesday, another round of heavy snow is expected across just   
   about all of the CA mountain ranges as a second, arguably stronger   
   upper level low dives south along the West Coast, closely following   
   the first. This will spike onshore flow and additional moisture   
   supply on the southern and eastern flanks of the upper low. Snow   
   levels will fall to around 1,000 ft in far northern California   
   (including the northern coastal range) Tuesday night, around   
   2,500ft in the Sierra Nevada, and just below 5,000 ft into the   
   Transverse Ranges. Snow will continue to fall across the state's   
   mountain ranges into Wednesday, but diminishing in intensity   
   considerably by sunrise.   
      
   California's mountain ranges welcome the snow, although it will   
   come down fast and furious both tomorrow and Tuesday. Through the   
   end of this discussion's timeframe (00Z Thu), multiple feet of   
   snow are forecast above 5,000ft along the Sierra Nevada. WPC   
   probabilities show high chances (>70%) for >30" of snow along   
   Donner Pass through 00Z Thursday and more snow still to come. The   
   WSSI shows a large swath of Extreme Impacts (Substantial   
   disruptions to daily life; extremely dangerous travel or impossible   
   driving conditions, extensive closures) for elevations generally   
   above 6,000ft, although some Extreme impacts as low as 5,000ft are   
   possible. Major to locally Extreme impacts are showing up in the   
   peaks of the San Gabriel and San Bernadino mountains, with mostly   
   Moderate-to-Major Impacts (increasingly more disruptive to travel   
   jumping from Moderate to Major). Note that there are also Minor to   
   locally Moderate Impacts along I-5 around Mount Shasta, signifying   
   potential travel delays for I-5 in the more elevated terrain of   
   northern CA.   
      
      
   ...Intermountain West...   
   Days 1-3...   
      
   Pacific moisture ahead of the longwave upper trough off the West   
   Coast will spill over the Cascades and Sierra Nevada and reach many   
   ranges across the Intermountain West today and into the upcoming   
   week. With a lack of a frigid airmass ahead of this healthy   
   moisture source, snow will largely be confined to many of the   
   taller mountain peaks that sorely need beneficial snowpack. The   
   heaviest snowfall will reside in the Bitterroots, the Lewis Range,   
   Sawtooth, and the Blue Mountains. Farther south, most   
   accumulations in the Great Basin, the Wasatch, Uinta, Mogollon Rim,   
   and CO/NM Rockies will be on the lighter side. The peaks around   
   Zion Nat'l Park on north along the Wasatch sport high (>70%)   
   chances of 72-hour snow totals for snowfall totals over a foot   
   through Wednesday. Monday will be the quietest day with most   
   mountain ranges into eastern Washington, Oregon, Idaho, and western   
   Montana seeing 1-4" of snowfall through tomorrow.   
      
   On Tuesday, the highly anomalous upper-low off the Pacific NW coast   
   will help to usher the initial upper low over southern CA east into   
   the Intermountain West, causing widespread height falls and a   
   larger footprint of Pacific moisture to track through the Rockies.   
   Snow levels will lower to the valley floors in western Mt and   
   northern ID, with some light snow possible even in the Salt Lake   
   City area. Still, the lack of a frigid airmass at the surface will   
   keep the bulk of the heavy snow in the mountains with ranges such   
   as the Wasatch, Bear River, Tetons, Uinta, and Wind River seeing   
   locally heavy snowfall along their peaks. Many of the CO Rockies   
   will also receive snowfall, but the heavier amounts >8" will be   
   confined to elevations above 9,000ft.   
      
   72-hour WPC probabilities show high chances (>70%) for snowfall   
   totals >8" for most of the Intermountain West's ranges, but the   
   locally heavier total's (>12") are most likely to occur in the   
   peaks of the Lewis Range, the Bitterroots, Sawtooth, Blue, Bear   
   River, Wasatch, and Uinta.   
      
      
   ...Upper Midwest & Great Lakes...   
   Day 3...   
      
   By 00Z Wednesday, the remnant yet vigorous negatively tilted   
   trough that was originally over southern CA late Monday will race   
   across the Rockies to the Dakotas. It will project excellent 500mb   
   PVA over the northern High Plains. The ECMWF SATs shows a roaring   
   150kt 200mb jet streak (wind speeds topping the 99.5 climatological   
   percentile) over the Southwest will place its divergent left-exit   
   region over the Great Plains. With the aid of lee-side downsloping   
   and low-level WAA across the Plains, an exceptionally deep surface   
   low will form over southern MT that reaches as low as 980mb Tuesday   
   morning, or MSLP values that are below the 1st climatological   
   percentile. As WAA ahead of the warm front reaches across the Upper   
   Midwest, strong isentropic ascent will ensue as the warm/moist air   
   runs into a colder/drier air-mass over northern ND and northern   
   MN. Precipitation initially starting as rain Tuesday afternoon will   
   changeover to snow over northeast MT, northern ND, and as far east   
   as the MN Arrowhead Tuesday night. Meanwhile, from northern MN and   
   northern WI to the northern tier of Michigan's Mitten, the   
   overrunning setup would favor a wintry mix of sleet and freezing   
   rain Tuesday night and into Wednesday morning. WPC probabilities   
   have increased and now show moderate chances (40-60%) for moderate   
   impacts (hazardous driving conditions requiring extra caution while   
   driving) due to ice accretion in parts of Michigan's Upper   
   Peninsula and extending to the northern tip of the mitten.   
   Accumulations in these areas could approach a quarter of an inch.   
      
   There remains a high degree of uncertainty in the storm track, as   
   well as when the transition to snow would occur. Snow beneath the   
   strengthening TROWAL over northeast MT and northern ND would   
   perhaps not only support heavy snow, but the impressive strength of   
   the cyclone itself would foster blowing snow on its northern and   
   western flanks. In terms of snowfall, the forecast probabilities   
   have dramatically increased. In portions of the MN Arrowhead,   
   chances are moderate-to-high (60-80%) for >8" of snowfall through   
   00Z Thu. Most of far northeast MT, northern ND, and northern MN   
   have moderate chances (50-70%) for >4" of snowfall, but this is an   
   area where any minor change in duration or placement in the   
   deformation axis could result in notable changes to the snowfall   
   forecast. Regardless, the pressure gradient will be tight enough to   
   where all of these areas have high chances (>80%) for Minor   
   Impacts (per WSSI-P) due to some combination of snowfall amounts of   
   blowing snow through the day on Wednesday.   
      
      
   ...Northeast...   
   Day 1...   
      
   The latest high-resolution guidance continues to favor areas   
   from southeast PA across the Delaware River and into NJ and as far   
   east as Long Island for light snowfall. WSSI-P values have   
   decreased in this area to only a 10% chance of minor impacts in   
   this region. Most expected snow totals are minor and likely to   
   range between a coating-2" from southeast PA (with elevation) on   
   east through central NJ, whereas the NYC metro forecasts have   
   dropped below an inch. Snow should peak in intensity over the next   
   several hours and conclude tomorrow morning.   
      
      
   Wegman/ Mullinax   
      
      
      
      
      
      
   $$   
      
   = = =   
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