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Winter

WPC’s winter severity index and its chances of snow and ice, and NWS’s winter and cold alerts. WPC draws for the lower 48.

NWS winter alerts / WPC selected map / WPC discussion: feeds current

NWS winter alerts: Feed current; checked .

WPC selected map: Feed current; checked .

WPC discussion: Feed current; checked .

Checked means retrieved, not newly issued. Each graphic retains its issue, observation, initialization or valid time. Site publishing status is separate.

Snow on the ground — NOHRSC pictures and retained history. Source analysis with qualified metadata times; separate from WPC’s winter forecasts and NWS warnings.

Chance of Moderate winter impacts or worse, Day 6, the 24 hours to 14 Nov 12:00Z

WPC: “WSSI does not depict official warnings and should always be used in context with official NWS forecasts and warnings.”

WPC’s WSSI-P chance

  • 5–10%
  • 10–20%
  • 20–30%
  • 30–40%
  • 40–50%
  • 50–60% highest in the lower 48
  • 60–70%
  • 70–80%
  • 80–90%
  • 90–95%
  • 95% or more
WPC’s probabilistic WSSI (WSSI-P), Moderate impacts or worse, valid to , WPC’s forecast from . Data: NOAA/NWS/WPC. The chance of at least that level of impact in the 24 hours, from WPC’s ensemble of forecasts. Each band runs to the next: a place lies in one. WPC described WSSI-P as experimental in 2022; its page carries no such label today.

Winter across the lower 48

Severity index (WSSI), overall

Day 1Moderate Impacts
Day 2Major Impacts
Day 3Major Impacts
Days 1–3Major Impacts

What drives it, Days 1–3: Snow amount: Minor Impacts, Snow load: Major Impacts, Ice accumulation: Winter Weather Area and Blowing snow: Major Impacts.

Chance of snow and ice

Day 1Day 2Day 3
At least 4 inches of snowHigh, 70%+High, 70%+High, 70%+
At least 8 inches of snowHigh, 70%+under 10%under 10%
At least 12 inches of snowunder 10%under 10%under 10%
At least a quarter inch of iceunder 10%under 10%under 10%

Each level is the highest WPC has drawn anywhere. WSSI’s levels and WPC’s chances are two products on two scales: a Moderate impact is not a Moderate chance.

Twelve NWS winter and cold alerts in the country: Winter Storm Watch and Frost Advisory.

NWS winter and cold alerts in the country

Twelve alerts in the country, in force or to come, by event as NWS names them.

Snow and ice

Winter Storm Watch 4
  1. Winter Storm Watch Not yet in effect From until East Turnagain Arm; Portage; Southern Kenai Mtns; Interior Kenai Peninsula; Turnagain Pass; West Prince William Sound & WhittierNWS Anchorage AK · NWS’s alert
  2. Winter Storm Watch Not yet in effect From until Thompson PassNWS Anchorage AK · NWS’s alert
  3. Winter Storm Watch Not yet in effect From until ErnestineNWS Anchorage AK · NWS’s alert
  4. Winter Storm Watch Not yet in effect From until Municipality of Skagway; Haines Borough and KlukwanNWS Juneau AK · NWS’s alert

Cold and freeze

Frost Advisory 8
  1. Frost Advisory Not yet in effect From until Marion; Lamar; Fayette; Winston; Walker; Blount; Etowah; Calhoun; Cherokee; Cleburne; Pickens; Tuscaloosa; Jefferson; Shelby; St. Clair; Talladega; Clay; Randolph; Sumter; Greene; Hale; Perry; Bibb; Chilton; Coosa; Tallapoosa; Chambers; Marengo; Dallas; Autauga; Lowndes; Elmore; Montgomery; Macon; Bullock; Lee; Russell; Pike; BarbourNWS Birmingham AL · NWS’s alert
  2. Frost Advisory Not yet in effect From until Dade; Walker; Catoosa; Whitfield; Murray; Fannin; Gilmer; Union; Towns; Chattooga; Gordon; Pickens; Dawson; Lumpkin; White; Floyd; Bartow; Polk; Paulding; Haralson; CarrollNWS Peachtree City GA · NWS’s alert
  3. Frost Advisory Not yet in effect From until Lauderdale; Colbert; Franklin; Lawrence; Limestone; Madison; Morgan; Marshall; Jackson; DeKalb; CullmanNWS Huntsville AL · NWS’s alert
  4. Frost Advisory Not yet in effect From until Ripley; Dearborn; Ohio; Switzerland; Carroll; Gallatin; Boone; Kenton; Campbell; Owen; Grant; Pendleton; Bracken; Robertson; Mason; Lewis; Franklin; Pickaway; Ross; Hamilton; Clermont; Brown; Highland; Adams; Pike; SciotoNWS Wilmington OH · NWS’s alert
  5. Frost Advisory Not yet in effect From until Fleming; Montgomery; Bath; Rowan; Estill; Powell; Menifee; Rockcastle; Jackson; Pulaski; Laurel; Wayne; McCreary; Whitley; Knox; Bell; Harlan; Elliott; Morgan; Johnson; Wolfe; Magoffin; Floyd; Lee; Breathitt; Knott; Owsley; Perry; Clay; Leslie; Letcher; Martin; PikeNWS Jackson KY · NWS’s alert
  6. Frost Advisory Not yet in effect From until Orange; Washington; Scott; Jefferson; Dubois; Crawford; Perry; Harrison; Floyd; Clark; Hancock; Breckinridge; Meade; Ohio; Grayson; Hardin; Bullitt; Jefferson; Oldham; Trimble; Henry; Shelby; Franklin; Scott; Harrison; Spencer; Anderson; Woodford; Fayette; Bourbon; Nicholas; Nelson; Washington; Mercer; Jessamine; Clark; Larue; Marion; Boyle; Garrard; Madison; Butler; Edmonson; Hart; Green; Taylor; Casey; Lincoln; Logan; Warren; Simpson; Allen; Barren; Monroe; Metcalfe; Adair; Russell; Cumberland; ClintonNWS Louisville KY · NWS’s alert
  7. Frost Advisory Not yet in effect From until Choctaw; Washington; Clarke; Wilcox; Monroe; Conecuh; Butler; Crenshaw; WayneNWS Mobile AL · NWS’s alert
  8. Frost Advisory Not yet in effect From until Greenup; Carter; Boyd; Lawrence; Lawrence; Dickenson; Buchanan; Wayne; Cabell; Lincoln; Putnam; Kanawha; Mingo; Logan; Boone; Clay; McDowell; WyomingNWS Charleston WV · NWS’s alert

NWS issues most winter alerts by forecast zone; a zone is a county or part of one. A Snow Squall Warning is drawn by NWS around the squall. NWS’s warnings on the Live map Storm Mode

WPC’s heavy snow and icing discussion

WPC’s Probabilistic Heavy Snow and Icing Discussion, issued , for to . WPC’s words, as written. Data: NOAA/NWS/WPC.

Washington Cascades Days 1-3

A couple of cold fronts will bring periods of snow to the higher Cascades this morning and again late Monday into Tuesday, mainly above 5000ft. This will affect Washington Pass/SR-20 (5476ft) which is still open. The probability of at least 4 inches of snow tomorrow into Tuesday is about 10-20% before milder air changes the snow over to rain there by Tuesday afternoon.

The probability of significant ice across the CONUS is less than 10 percent.

Fracasso

The whole discussion, as WPC wrote it
Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
142 AM EST Sun Nov 8 2026

Valid 12Z Sun Nov 08 2026 - 12Z Wed Nov 11 2026

...Washington Cascades...
Days 1-3...

A couple of cold fronts will bring periods of snow to the higher
Cascades this morning and again late Monday into Tuesday, mainly
above 5000ft. This will affect Washington Pass/SR-20 (5476ft) which
is still open. The probability of at least 4 inches of snow
tomorrow into Tuesday is about 10-20% before milder air changes the
snow over to rain there by Tuesday afternoon.


The probability of significant ice across the CONUS is less than
10 percent.


Fracasso

Not an official warning service. Warnings and watches are the National Weather Service’s, outlooks and reports the Storm Prediction Center’s and the Weather Prediction Center’s (Data: NOAA/NWS, NOAA/SPC, NOAA/WPC). When a warning is issued for you, act on it, and use weather.gov or a NOAA Weather Radio for where you are.