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HawaiiSite status

Winter

WPC’s winter severity index and its chances of snow and ice, and NWS’s winter and cold alerts in Hawaii. 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.

Winter Storm Severity Index: Blowing snow, Days 1–3

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

Hawaii is outside WPC’s winter products, which are drawn for the conterminous states alone. NWS’s alerts below still cover it.

WPC’s WSSI levels

  • Winter Weather Area
  • Minor Impacts
  • Moderate Impacts
  • Major Impacts
  • Extreme Impacts
WPC’s Winter Storm Severity Index, blowing snow, Days 1–3, valid to , issued . Data: NOAA/NWS/WPC. The impact a winter storm’s forecast snow, ice and wind may have on daily life, from WPC’s reading of the National Digital Forecast Database: not a warning, and not a chance.

Winter in Hawaii

WPC’s winter severity index and its chances of snow and ice are drawn for the conterminous states alone, so nothing of theirs is shown for Hawaii. That is not a forecast of no snow.

No NWS winter or cold alert in Hawaii.

NWS winter and cold alerts in Hawaii

No winter storm, blizzard, ice, snow squall, lake-effect, freezing fog, cold or freeze watch, warning or advisory in Hawaii.

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 for Hawaii, winter

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.

Sierra Nevada into the Intermountain West & Four Corners Day 2-3

An impressive full-latitude upper trough, represented by NAEFS height anomalies falling below the 10th percentile along most of the Pacific Coast, will gradually pivot eastward into early next week. Downstream of this deepening trough, a subtropical jet streak will amplify and surge northeast, with downstream diffluence overlapping with intensifying mid-level divergence to produce robust deep layer ascent across the Southwest and Intermountain West this weekend.

Moisture embedded within a pronounced IVT plume (peak IVT above 500 kg/m/s from the West-WRF centered over the Southwest) will lift into the increasing ascent, resulting in widespread precipitation D2 and D3 from southern CA through the Northern Rockies. The WAA accompanying the IVT will push snow levels to 9000-10000 ft across the Intermountain West (slightly lower 8000 ft in ID/MT), keeping most of the precipitation rain. However, accumulating snow is likely in the higher elevations, with periodic lowering of snow levels to 7000-9000 ft (near the NBM 10th percentile, varying with location) thanks to steep lapse rates aloft and some enhanced ascent through 700-600mb fgen and upslope forcing.

Some light snow is possible D1, but in general accumulating snow will occur primarily on D2 and D3. During this time, the higher elevations of the Sierra will be favored for the heaviest accumulation, with a 60% chance of at least 12 inches, with local maxima approaching 2 feet. Additional heavy snow exceeding 6 inches is likely (>60%) across the higher elevations of the Sawtooth of ID, the Uintas of UT, and the San Juans of CO, where locally 12+" is possible. All of this snow will likely be comprised of less- than-climatological SLR, leading to substantial snow load impacts (20-50% chance of at least moderate impacts due to snow load from the WSSI-P.

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

Weiss

The whole discussion, as WPC wrote it
Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
210 PM EDT Thu Oct 29 2026

Valid 00Z Fri Oct 30 2026 - 00Z Mon Nov 02 2026

...Sierra Nevada into the Intermountain West & Four Corners...
Day 2-3...

An impressive full-latitude upper trough, represented by NAEFS
height anomalies falling below the 10th percentile along most of
the Pacific Coast, will gradually pivot eastward into early next
week. Downstream of this deepening trough, a subtropical jet streak
will amplify and surge northeast, with downstream diffluence
overlapping with intensifying mid-level divergence to produce
robust deep layer ascent across the Southwest and Intermountain
West this weekend.

Moisture embedded within a pronounced IVT plume (peak IVT above 500
kg/m/s from the West-WRF centered over the Southwest) will lift
into the increasing ascent, resulting in widespread precipitation
D2 and D3 from southern CA through the Northern Rockies. The WAA
accompanying the IVT will push snow levels to 9000-10000 ft across
the Intermountain West (slightly lower 8000 ft in ID/MT), keeping
most of the precipitation rain. However, accumulating snow is
likely in the higher elevations, with periodic lowering of snow
levels to 7000-9000 ft (near the NBM 10th percentile, varying with
location) thanks to steep lapse rates aloft and some enhanced
ascent through 700-600mb fgen and upslope forcing.

Some light snow is possible D1, but in general accumulating snow
will occur primarily on D2 and D3. During this time, the higher
elevations of the Sierra will be favored for the heaviest
accumulation, with a 60% chance of at least 12 inches, with local
maxima approaching 2 feet. Additional heavy snow exceeding 6 inches
is likely (>60%) across the higher elevations of the Sawtooth of
ID, the Uintas of UT, and the San Juans of CO, where locally 12+"
is possible. All of this snow will likely be comprised of less-
than-climatological SLR, leading to substantial snow load impacts
(20-50% chance of at least moderate impacts due to snow load from
the WSSI-P.

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

Weiss

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.