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   FOUS11 KWBC 171947   
   QPFHSD   
      
   Probabilistic Heavy Snow and Icing Discussion   
   NWS Weather Prediction Center College Park MD   
   247 PM EST Tue Feb 17 2026   
      
   Valid 00Z Wed Feb 18 2026 - 00Z Sat Feb 21 2026   
      
      
   ...Pacific & Interior Northwest...   
   Days 1-3...   
      
   An active pattern will continue through midweek as a series of   
   shortwaves rotate through a broad upper trough.  The closed low   
   currently centered off of the Washington-Oregon coast will translate   
   into an open wave, with the trough axis forecast to move inland   
   overnight.  While additional accumulations will be relatively light,   
   this transition will provide the necessary forcing and cold air to   
   support additional snow and drive snow levels lower through   
   Wednesday morning.   
      
   A brief period of shortwave ridging will support a lull in   
   precipitation on Wednesday.  During this time, expect a slight   
   rebound in snow levels before the next impulse arrives.   
      
   By Thursday, an upstream shortwave diving south from the British   
   Columbia coast will move inland.  While this feature will support an   
   uptick in regional precipitation, the more robust forcing and deeper   
   moisture are expected to focus from southeastern Oregon southward.   
   Low snow levels at the onset will be driven even lower by this   
   system, maintaining the threat of lowland snow accumulations.   
      
   Probabilities for additional accumulations exceeding 8 inches are   
   highest over the southern Oregon Cascades and the southern Oregon   
   coastal ranges above 2,000 ft.  Probabilities for accumulations over   
   an inch climb to over 30 percent for the Portland area Wednesday   
   into early Thursday.   
      
   Precipitation is expected to diminish by late Thursday as the trough   
   axis departs to the east.  Upper-level ridging will build in its   
   wake, likely persisting through late Friday - diminishing the   
   potential for widespread heavy snowfall.   
      
   ...California...   
   Days 1-3...   
      
   ...Multiple days of heavy, disruptive snowfall for the California   
   ranges...   
      
   Successive Pacific storms will funnel deep moisture into California   
   through midweek.  Heavy snow continues this evening as amplified   
   energy digs into the base of an upper trough moving onshore.  Heavy   
   snow will persist through the overnight into Wednesday along the   
   Sierra Nevada and southern California ranges.   
      
   Snow levels will plummet to 1,000 ft in far northern California,   
   2,500 ft in the Sierra Nevada, and 4,000-5,000 ft in the Transverse   
   Ranges tonight.  Rates are expected to diminish on Wednesday as the   
   leading wave moves east; however, snow levels will remain low,   
   supporting snow accumulations down to 1,000 ft in central California.   
      
   On Thursday, phasing shortwaves diving southeast into the state will   
   support additional moderate snow across most ranges, although   
   intensity will be less than previous days.   
      
   Storm total accumulations exceeding two feet are likely for the   
   northern Sierra Nevada above 3,000-4,000 ft and in the southern   
   Sierra above 4,000-5,000 ft - with several feet possible at the   
   highest elevations.  The WSSI-P continues to indicate widespread   
   Extreme impacts are likely for the central and southern Sierra   
   Nevada through into Wednesday before gradually diminishing.  At   
   least Moderate Impacts along the Sierra Nevada I-80 corridor are   
   expected to persist into Friday.   
      
   In Southern California, WPC probabilities indicate storm total   
   accumulations over a foot are highest in the Transverse and northern   
   Peninsular ranges above 6,000 ft.   
      
   Similar to the Northwest, upper ridging will provide a break in the   
   heavy snowfall threat beginning late Thursday and continuing into   
   Friday.   
      
   ...Intermountain West/Southwest to the Rockies...   
   Days 1-3...   
      
   Pacific moisture spilling over the Cascades and Sierra-Nevada will   
   provide a much-needed boost to the Intermountain and Rocky Mountain   
   snowpack.   
      
   Following a warm start, snow levels will drop into the valleys as   
   the leading shortwave moves inland on Wednesday.  A brief lull is   
   expected on Thursday, except for Nevada and the Four Corners region,   
   where the next shortwave will bring the threat for heavy mountain   
   snow into Friday.   
      
   Probabilities for storm total amounts over a foot exceed 70 percent   
   for several areas including the high elevations of the Nevada   
   mountains, the southern Utah mountains, the northern Arizona plateaus   
   to the central Mogollon Rim, and much of the central Rockies -   
   particularly the northern Utah and western Colorado ranges.   
      
      
   ...Northern Plains & Upper Great Lakes...   
   Days 1-2...   
      
   Current WV satellite imagery indicates a well-defined shortwave   
   trough navigating through the Rockies with a broad, diffluent axis   
   positioned downstream over the Northern Plains to Upper Midwest.   
   As this trough migrates northeast into the Northern Plains, the   
   expectation is for the trough to become negatively tilted and   
   expand eastward across the Northern Plains through the Upper   
   Midwest. At the surface, the development and subsequent maturation   
   of an area of low pressure will occur as the surface reflection   
   materializes and strengthens thanks to its positioning within the   
   LFQ of a strengthening subtropical jet streak arcing from the   
   Desert Southwest to the Great Lakes. This low is then expected to   
   move very slowly through Wednesday before gradually filling over   
   the western Great Lakes Thursday night, leading to an eventual end   
   of the storms impacts within the D1-2 time frame.   
      
   As this low tracks slowly eastward, it will interact with   
   impressive IVT surging above the 99th climatological percentile   
   into Minnesota according to NAEFS and global ensemble depictions, a   
   testament to a deep moisture feed that this storm will be able to   
   tap into when maturing over the Upper Midwest. The accompanying   
   moisture and theta-e ridge axis will then wrap cyclonically around   
   the system and lift into a pronounced TROWAL. The associated   
   synoptic lift, aided by increasing WAA, will expand precipitation   
   across the northern tier of the CONUS from far eastern MT through   
   the western Great Lakes. Periods of heavy snow are likely as   
   strongly sloped FGEN driving omega into the TROWAL supports heavy   
   precipitation rates. The most impressive ascent appears to   
   intersect the DGZ, so despite this being subjectively elevated   
   (nearing 500 mb), it will support heavy snow rates and dynamic   
   cooling into a column that is initially too warm to support snow.   
   However, once precipitation changes to snow, it will become heavy,   
   supported by the WAA/FGEN beneath the TROWAL and accompanying CSI   
   evident in cross-sections, supporting rates that will likely exceed   
   1"/hr at times (>70% chance). These intense rates will be   
   accompanied by strong and gusty winds, resulting in widespread   
   moderate impacts (40-80% chance) from ND through the Arrowhead of   
   MN. It is in this swath of the Upper Midwest where there are   
   moderate-to-high chances (50-90%) for snowfall totals >6",   
   including as far east as the northern shores of MI's Upper   
   Peninsula. The biggest change from the previous forecast was an   
   increase in the probabilities for >6" across the Arrowhead of   
   Minnesota where a broad area of >90% probability exists with >80%   
   for over 12".   
      
   Lower probabilities exist for some localized areas of northern ND   
   and northern MN that could see totals approach 12", but it is the   
   MN Arrowhead that will likely be the area of highest impact with   
   regards to snow totals for the event. At least 1-2 feet of snow   
   with totals topping 24" increasingly likely from Two Harbors to   
   Grand Portage and points inland along the MN-61 state highway that   
   parallel's the North Shore of Lake Superior. The WSSI-P continues   
   to show elevated chances (40-70%) for locally Major Impacts   
   (considerable disruptions; dangerous driving conditions and   
   widespread closures) driven heavily by the snow amounts forecast   
   across the area.   
      
   Additionally, with the pronounced WAA rotating around the surface   
   low, an area of freezing rain is also expected, especially from   
   near Duluth, MN eastward across northern WI and into northern MI   
   where the warm nose will be most prevalent while surface temps   
   remain sub-freezing. This sets the stage for a freezing rain/icing   
   event that could last for over 24 hours in parts of northern WI and   
   northern MI. WPC probabilities are moderate (40-80%) for at least   
   1/10 inch of ice, with locally more than a quarter inch possible,   
   most likely across the tip of Michigan's Mitten, mainly areas east   
   of Grand Traverse Bay.   
      
      
   ...Northeast...   
   Day 2...   
      
   There has been very little change to the overall synoptic evolution   
   anticipated for the D2 time frame across the Northeastern U.S. A   
   strong surface low moving slowly across the Dakotas/Minnesota   
   Wednesday will remain entrenched within an elongated mid-level   
   trough extending into the Mid- Atlantic states. Vorticity lobes   
   downstream of this wave will spread northeast from the Mid-Atlantic   
   states into the Northeast, before getting sheared to the east as   
   mid-level flow becomes strongly confluent south of the secondary   
   shortwave energy crossing Maine and Nova Scotia. The resultant mid-   
   level PVA and divergence will overlap with a narrow ribbon of   
   impressive low- level WAA to produce a stripe of heavy   
   precipitation from Upstate NY through southern/central New England.   
      
   This precipitation will expand eastward from the Great Lakes   
   Wednesday morning, then exiting off the New England coast by   
   Thursday morning. Guidance is now coming into better agreement on   
   the placement over 925-850mb layer-averaged FGEN zone over the   
   southern tier of NY, that is favoring a swath of snow just north   
   of the FGEN band. Thermally, the antecedent column is marginal to   
   support wintry precipitation, and it appears any significant   
   snowfall accumulation will be contained both to higher elevations   
   above 1,000 ft, and to where the most intense dynamic cooling can   
   overwhelm the above- freezing low levels. The most significant   
   accumulations are most likely from upstate NY into western VT where   
   conditional instability into a DGZ is just supportive enough to   
   generate locally heavy rates.   
      
   This is reflected by WPC probabilities that reach as high as   
   10-40% for 4+ inches of snow, especially in the Adirondacks and   
   Greens, with moderate probabilities (40-70%) for >2 inches   
   covering much of central New England and the northern half of   
   upstate NY. It is important to note that the WSE mean snowfall for   
   much of this area remains below the maximum values, so some   
   locally higher amounts are probable where any banding persists.   
   South of this axis of moderate to heavy snow, a corridor of icing   
   exceeding 0.1" is possible (30-50% chance) from the southern shore   
   of Lake Ontario with low chances (10-30%) for over one-quarter   
   inch.   
      
      
   ...Central Plains...   
   Day 2-3...   
      
   Wednesday night, a potent shortwave trough ejecting out of the   
   Central Rockies will take on a negative tilt as it heads into the   
   Central Plains. To the north of the 500mb vort max, strong 700mb   
   Q-vector confluence will focus a narrow area of strong vertical   
   velocities, coinciding with a pronounced TROWAL forming over the   
   Sand Hills of NE and southern SD early Thursday morning. While   
   there is lingering spread in guidance regarding the placement of   
   this band as it forms as far west as eastern WY and tracks as far   
   east as the MO River Valley Thursday evening, most guidance agrees   
   the impressive synoptic-scale support aloft (left-exit region of a   
   250mb jet streak over head) and strong SErly 850mb WAA will   
   support heavy snowfall rates. Latest WPC probabilities show   
   moderate chances (40-80%) for >4" of snow from eastern WY on east   
   along the NE/SD border and into southeast SD. It is worth noting   
   there are low chance probabilities (10-40%) for >8" of snowfall in   
   northwestern NE and along the southwest SD border. Given the   
   strong dynamics and banding potential, these are the kind of setups   
   where seeing snowfall totals are low chance over 48 hours out, but   
   are very much within reason. Residents in the Central Plains   
   should monitor the forecast from their local WFO closely in the   
   coming days.   
      
      
   Mullinax/Kleebauer/Pereira   
      
      
      
   $$   
      
   = = =   
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