043
FXUS21 KWNC 181949
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EST NOVEMBER 18 2025
SYNOPSIS: MID-LEVEL LOW PRESSURE CENTERED OVER THE INTERIOR WEST AT THE
BEGINNING OF WEEK-2 IS PREDICTED TO REBUILD BY THE END OF WEEK-2. WITH STRONG
MID-LEVEL HIGH PRESSURE OVER THE HIGHER LATITUDES OF WESTERN NORTH AMERICA,
THIS PATTERN FAVORS COLD ARCTIC AIR SINKING SOUTH FROM THE WESTERN HALF OF
CANADA INTO THE WESTERN CONTIGUOUS U.S. (CONUS), LEADING TO INCREASED CHANCES
FOR MUCH BELOW NORMAL TEMPERATURES FOR THE NORTHWESTERN AND CENTRAL CONUS.
ENHANCED ODDS FOR HIGH WINDS ACROSS THE GREAT PLAINS WOULD RESULT IN COLDER
WIND CHILL TEMPERATURES. AN INCREASED RISK OF HEAVY SNOW IS ANTICIPATED FOR
HIGH ELEVATIONS INITIALLY FOR THE CASCADES, KLAMATH MOUNTAINS, AND SIERRA
NEVADA, SHIFTING TO THE ROCKIES AND UTAH TO FINALLY THE UPPER MIDWEST.
HAZARDS
SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES FOR PARTS OF INLAND AREAS OF THE
PACIFIC NORTHWEST AND NORTHERN GREAT BASIN, WED-THU, NOV 26-27.
SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES FOR PARTS OF THE GREAT PLAINS AND
NORTHERN ROCKIES, THU-TUE, NOV 27-DEC 2.
SLIGHT RISK OF HEAVY SNOW FOR THE CASCADES, THU-TUE, NOV 27-DEC 2.
SLIGHT RISK OF HEAVY SNOW FOR THE KLAMATH MOUNTS AND SIERRA NEVADA, FRI-TUE,
NOV 28-DEC 2.
SLIGHT RISK OF HEAVY SNOW FOR PARTS OF THE ROCKIES AND UTAH, FRI-TUE, NOV
28-DEC 2.
SLIGHT RISK OF HEAVY SNOW FOR PARTS OF THE NORTHERN AND CENTRAL PLAINS, UPPER
MISSISSIPPI VALLEY, AND GREAT LAKES REGION, SAT-TUE, NOV 29-DEC 2.
SLIGHT RISK OF HIGH WINDS ACROSS THE GREAT PLAINS, WED-TUE, NOV 26-DEC 2.
SLIGHT RISK OF HIGH WINDS FROM THE COPPER RIVER IN ALASKA TO NORTHERN PORTIONS
OF SOUTHEASTERN ALASKA, NOV 26-NOV 29.
DETAILED SUMMARY
FOR FRIDAY NOVEMBER 21 - TUESDAY NOVEMBER 25:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR WEDNESDAY NOVEMBER 26 - TUESDAY DECEMBER 02: MID-LEVEL RIDGING OVER ALASKA
AND THE NORTHEASTERN PACIFIC CONTINUES TO BE PREDICTED, CONTRIBUTING TO A
DEEPENING MID-LEVEL TROUGH DOWNSTREAM OVER THE WESTERN CONUS. THE ECENS
ENSEMBLE MEAN CONTINUES TO INDICATE A MORE AMPLIFIED TROUGH CENTERED FURTHER
WEST (OVER THE GREAT BASIN) COMPARED TO THE GEFS (OVER THE ROCKIES). TROUGHING
ACROSS THE WEST AT THE BEGINNING OF WEEK-2 IS ANTICIPATED TO SHIFT EASTWARD TO
THE CENTRAL CONUS BY DAY 9 (NOV 27). AS THIS TROUGH MOVES EASTWARD ACROSS THE
NORTHERN TIER, AMPLIFIED TROUGHING IS PREDICTED TO RE-DEVELOP ACROSS THE WEST
AROUND DAY 9 (NOV 29).
COLD ARCTIC AIR IS ANTICIPATED TO SINK SOUTHWARD FROM WESTERN CANADA AT THE
BEGINNING OF THE PERIOD, INITIALLY BRINGING MUCH BELOW NORMAL TEMPERATURES TO
THE NORTHWEST, SHIFTING TO THE GREAT PLAINS BY NOV 27. A SLIGHT RISK OF MUCH
BELOW NORMAL TEMPERATURES IS POSTED FOR INLAND AREAS OF THE PACIFIC NORTHWEST
AND NORTHERN GREAT BASIN, NOV 26-27, AND FOR THE GREAT PLAINS, NOV 27-DEC 2.
THERE ARE DIFFERENCES AMONG THE PETS OF WHERE AND WHEN THE LOWEST TEMPERATURES
OCCUR, SO A BROAD AREA IS HIGHLIGHTED WITH THE MUCH BELOW NORMAL TEMPERATURE
HAZARD ACROSS THE GREAT PLAINS. THE GEFS, ECENS, AND CANADIAN PROBABILISTIC
EXTREMES TOOLS (PET) GENERALLY INDICATE AT LEAST A 20% CHANCE OF MINIMUM
TEMPERATURES FALLING TO THE LOWEST 15TH CLIMATOLOGICAL PERCENTILE AND BELOW 20
DEG F ACROSS MANY PARTS OF THE HIGHLIGHTED AREAS. ADDITIONALLY, A SLIGHT RISK
OF HIGH WINDS IS DESIGNATED FOR THE GREAT PLAINS THROUGHOUT WEEK-2, WHICH COULD
SUPPORT COLDER WIND CHILL TEMPERATURES.
A SERIES OF SURFACE LOWS AND FRONTS ARE PREDICTED TO DEVELOP ACROSS THE WESTERN
CONUS ASSOCIATED WITH THE SERIES OF MID-LEVEL TROUGHS, SUPPORTING INCREASED
LIKELIHOOD FOR ENHANCED SNOWFALL FOR VARIOUS AREAS. A SLIGHT RISK OF HEAVY
SNOW IS POSTED FOR THE CASCADES, NOV 27-DEC 2, FOLLOWED BY THE KLAMATH
MOUNTAINS, SIERRA NEVADA, ROCKIES AND UTAH, NOV 28-DEC 2. A SLIGHT RISK OF
HEAVY SNOW IS CONTINUED FOR PARTS OF THE NORTHERN AND CENTRAL PLAINS, UPPER
MISSISSIPPI VALLEY, AND GREAT LAKES REGION, NOV 29-DEC 2, AS SURFACE LOWS ARE
ANTICIPATED TO TRACK FROM THE CENTRAL CONUS TO THE GREAT LAKES REGION.
UNCALIBRATED ENSEMBLES SHOW INCREASED CHANCES FOR SOME OF THESE AREAS RECEIVING
GREATER THAN 4 INCHES OVER A 3-DAY PERIOD (GREATER THAN 6 INCHES LOCALLY).
ANTICIPATED GUSTY WINDS COMBINED WITH SNOWFALL COULD SUPPORT BLOWING SNOW AND
RESULTING DECREASED VISIBILITY, ESPECIALLY ACROSS PARTS OF THE NORTHERN AND
CENTRAL PLAINS DURING THE THANKSGIVING TRAVEL PERIOD. THERE COULD BE SOME WRAP
AROUND LAKE EFFECT SNOW ACROSS THE SOUTHERN GREAT LAKES BUT DIFFICULT TO
DETERMINE AT THIS TIME.
SURFACE LOW PRESSURE OVER THE GULF OF ALASKA COMBINED WITH ADJACENT SURFACE
HIGH PRESSURE OVER BRITISH COLUMBIA AND THE YUKON MAY LEAD TO A TIGHT PRESSURE
GRADIENT ALONG COASTAL PORTIONS OF SOUTH-CENTRAL AND SOUTHEASTERN ALASKA. THIS
PATTERN MAY BE FAVORABLE FOR GAP WINDS IN CHANNELS IN SOME OF THESE AREAS
DURING THANKSGIVING TRAVEL. THEREFORE A SLIGHT RISK OF HIGH WINDS IS DESIGNATED
FROM THE COPPER RIVER IN ALASKA TO NORTHERN PORTIONS OF SOUTHEASTERN ALASKA,
NOV 26-29.
FORECASTER: MELISSA OU
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