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   FOUS11 KWBC 250741   
   QPFHSD   
      
   Probabilistic Heavy Snow and Icing Discussion   
   NWS Weather Prediction Center College Park MD   
   241 AM EST Sun Jan 25 2026   
      
   Valid 12Z Sun Jan 25 2026 - 12Z Wed Jan 28 2026   
      
      
   ...Ongoing major winter storm to bring crippling icing,=20   
   significant sleet, and heavy snow from the Southern Rockies/Plains=20   
   through the Southeast and up the Atlantic Coast into New England...   
      
   Meteorological Overview...   
   Forecast remains on track as a massive winter storm is underway   
   across a significant portion of the country, currently extending=20   
   from the southern Rockies to the Mid-Atlantic early this morning.   
   By the start of the forecast period (12z Sun), widespread moderate   
   to heavy snow, sleet, and freezing rain is expected to span from=20   
   New Mexico to New York and continue to primarily impact regions=20   
   from the Ohio/Tennessee valleys and Mid-Atlantic to New England   
   through the overnight hours tonight. This event is forecast to=20   
   gradually wane across New England and the Interior Northeast on=20   
   Monday.   
      
   The driver of this winter storm is the interaction of a northern=20   
   stream trough diving out of the north-central U.S. this morning   
   along with a few southern stream impulses ejecting from the   
   southern Rockies and Plains. As these features accelerate eastward   
   today and interact into a more amplified and larger trough over=20   
   the central CONUS tonight, impressive subtropical moisture will   
   continue spreading east/northeast both from the Pacific and the=20   
   Gulf, with IVT exceeding the 97.5th climatological percentile=20   
   according to NAEFS. The rich moisture from the south will accompany   
   strong 850-700mb WAA that results in classic over- running along=20   
   an area of 850-700mb FGEN stretching from atop the Mid-MS and OH/TN   
   VLY to the Mid- Atlantic this morning, reaching New England this=20   
   evening and then finally exiting the Atlantic Coast on Monday. In=20   
   addition to the classic overrunning/WAA precipitation, the=20   
   placement of the upper jet as it strengthens and pivots poleward,=20   
   will support intense bands of snowfall (cross sections suggest a=20   
   high threat for CSI and even potential CI within the strongest WAA)   
   which will support snowfall rates of 1-2+"/hr at times where it is   
   all snow, and intense sleet/freezing rain rates in mixed zones.   
      
   Farther to the east, the intense CAD (Cold Air Damming) signature=20=20   
   east of the Appalachians will only slightly retreat through   
   tonight. With rapid warming aloft due to increasing southerly 850mb   
   winds over 50 kts and subfreezing temperatures remaining in the=20   
   low- levels, sleet is expected to be as far north as southern MD by   
   12z this morning and continuing marching northward through the day   
   as far as the southern New England coastline. This will cut down on   
   snowfall totals along I-95 from Washington D.C. to NYC, and will   
   also increase the potential for ptype to turn towards dangerous   
   freezing rain by late this afternoon.   
      
   With intense IVT pushing PWs to above the 99th percentile, there   
   will be plentiful moisture to work with everywhere from the OH VLY   
   through New England. This will support heavy precipitation=20   
   accumulations regardless of p-type, so substantial impacts are=20   
   expected for a large swath of the nation. The heaviest snow is=20   
   expected from the Ohio Valley into the Northeast (more outlined=20   
   below). Farther south, crippling icing is expected for parts of=20   
   AR/LA/MS/TN early today, as well as the Carolinas and Virginia   
   through tonight, with exceptional sleet accumulations of several=20   
   inches progged in between the snow and ice from Arkansas through=20   
   Kentucky, and then for portions of the Mid- Atlantic as well.   
      
      
   Heavy Snow/Sleet...   
   Snow will be winding down across the Southern Plains and Mid-MS VLY   
   by 12z this morning, but continues just east through the OH VLY. This   
   still supports an long swath of >6" of snowfall from IN to ME and   
   an increasing potential for >18" across the Interior Northeast and   
   New England.   
      
   48-hr WPC probabilities (most snow occurring within the first=20   
   24-hr period), are high (>70%) for an additional 8"+ from central=20   
   OH through central ME and most of New England. Probabilities for=20   
   18"+ have increased and are 50-80% across Upstate NY through much=20   
   of New England as far north as central VT/NH. A heavy band of=20   
   snowfall on the NW side of the low and within the strengthening jet   
   streak will support 1+"/hr snowfall across the Ohio Valley through   
   this afternoon as reflected by the WPC prototype snowband tool.=20   
   With this band likely translating along its long axis, heavy=20   
   snowfall will have a temporal extent sufficient for more than 8=20   
   inches. Locally 15+ inches is possible across southern OH.=20   
      
   The heaviest snow from this event is likely across New England and   
   the Interior Northeast where p-type changes are not likely. This=20   
   is also where the longest duration of heavy snowfall within both=20   
   WAA banded structures and then potentially a more=20   
   pivoting/laterally translating band will develop as secondary low=20   
   pressure skirts off the Mid- Atlantic coast and just inside the=20   
   Benchmark (40N/70W). This will support a longer duration of=20   
   2+"/hr snowfall, and WPC 48-hr probabilities reach above 90% for=20   
   12+ inches, and locally as much as 2 feet is possible (especially=20   
   in the Worcester Hills, Berkshires, and Catskills, as well north of   
   Boston along the coastal front) where WPC probabilities for 24"=20   
   are 20-40%. WPC's Snowband Probability Tracker (SPT) using the 00z   
   HREF is very impressive for 1-2"+/hr rates around 18Z near=20   
   northern NJ and eventually across New England beginning around 21Z   
   and lasting across eastern New England until 06Z tonight.=20   
   Regarding coverage of heavy snow, this will be a widespread 12"+=20   
   snowfall event for most of southern and central New England as well   
   as central/northern PA.   
      
   In addition, with the intense WAA, a warm nose aloft (generally   
   800-700mb) will gradually create a warm nose above 0C shifting   
   through the Mid-Atlantic. The cold depth below this warm nose=20   
   appears to be in many places above the 75th-90th percentile for=20   
   freezing rain, indicating primary sleet for these interior areas=20   
   as p-type transition occurs, with significant sleet accumulations=20   
   of multiple-inches expected. This will result in tremendous impacts   
   to travel in these areas.   
      
   The WSSI shows widespread Major Impacts (considerable disruptions   
   to daily life: dangerous to impossible driving conditions,=20   
   widespread closures, and disruptions to infrastructure) from the=20   
   OH VLY to New England. Every major market along the I-95=20   
   metropolitan corridor (Washington D.C. to Boston and even as far=20   
   north as Portland, ME) are expecting major impacts due to snow   
   amounts. The D.C/Baltimore area on north to Philly and NYC are=20   
   likely to see some inclusion of sleet and potentially some freezing   
   rain, but it will still result in significant impacts when=20   
   accounting for heavy snowfall that is expected to exceed warning=20   
   criteria (5-6"). Gusty winds increasing with the developing=20   
   surface low off the Mid-Alantic coast may also lead to a brief=20   
   period of near-blizzard conditions across eastern New England,=20   
   including Boston, late tonight. A reminder that bitterly cold=20   
   temperatures will follow in wake of this storm through the middle=20   
   of next week throughout the eastern U.S., so snow/sleet impacts=20   
   will linger for many days even after precipitation ends.   
      
   Freezing Rain...   
   The most lasting impact will come as a result of significant to=20   
   locally catastrophic ice accumulations due to prolonged periods of=20   
   freezing rain. Just like the swath of >6" of snowfall, the areal=20   
   coverage of impactful freezing rain remains expansive across the=20   
   Mid- South, where the event concludes by midday today and a=20   
   secondary area east of the Cumberland Gap from northern GA through=20   
   central VA and southern MD, including much of the Carolinas. In=20   
   these regions, at least 0.25" of total ice is expected to be=20   
   widespread, with a more narrow corridor embedded within of at least   
   an additional 0.5" (30-60%), highest today across the NC Piedmont   
   into south-central VA. This amount of freezing rain can create   
   widespread power outages and tree damage, as well as treacherous to   
   impossible travel at times.   
      
   For LA, MS, TN, ice accumulation is "additional" beyond what will=20   
   occur before 12Z (6am CST), so local amounts above 1" are actually   
   expected to be much more widespread than the very low=20   
   probabilities suggest for solely today's precipitation. The=20   
   greatest additional icing after 12Z today is located across the=20   
   Mid- Atlantic, where up to 0.5" is possible. With very cold weather   
   in place, this will become a life- threatening situation where=20   
   freezing rain amounts are highest (including the Lower MS VLY and=20   
   Mid-South) with potentially impossible travel due to downed trees=20   
   and power lines.   
      
      
   Key Messages for this system are linked below (Key Message 2).   
   Key messages for the widespread extreme cold are linked below as   
   well (Key Message 1).   
      
      
   ...Great Lakes...   
   Days 2-3...   
      
   Broad cyclonic flow will persist across the east, but an embedded   
   shortwave within this trough will dig out of Alberta Monday night   
   and then cross the Great Lakes from northwest to southeast during   
   Tuesday. This will enhance CAA, leading to another round of lake   
   effect snow (LES), although the duration and intensity of this   
   event should be modest overall, some moderate accumulations are   
   still expected beginning D2-3 and lingering beyond this forecast=20   
   period. LES from Lake Erie should be minimal as that lake is now=20   
   ice covered according to GLERL and should continue to see ice   
   thicken with very cold temperatures in place, but elsewhere, WPC=20   
   probabilities are high for 4+ inches near the Tug Hill Plateau.   
      
      
   Snell/Weiss   
      
      
      
      
   ...Winter Storm Key Messages are in effect. Please see current=20   
    Key Messages below...   
      
   https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late=   
   stKeyMessage_1.png__;!!DZ3fjg!9sseXzdxj0AGHqtE9PxBDvpaCHTgyf0kBlV0VQClBi97u=   
   cbSjEzZJILpGM3a97dsD08_MPYg2KvCXzcmJFn55hXmNHY$=20   
      
   https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/key_messages/Late=   
   stKeyMessage_2.png__;!!DZ3fjg!9sseXzdxj0AGHqtE9PxBDvpaCHTgyf0kBlV0VQClBi97u=   
   cbSjEzZJILpGM3a97dsD08_MPYg2KvCXzcmJFn5V8ppWtM$=20   
      
      
      
   $$   
      
   =3D =3D =3D   
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