761
FXUS21 KWNC 191844
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT OCTOBER 19 2025
SYNOPSIS: STRONG LOW PRESSURE AT THE SURFACE AND MID-LEVELS IS FAVORED TO SHIFT
EASTWARD FROM THE NORTHEASTERN PACIFIC AND BRING AN ELEVATED RISK OF HAZARDOUS
WINDS, HEAVY PRECIPITATION, AND HIGH ELEVATION HEAVY SNOWFALL ACROSS THE
PACIFIC NORTHWEST DURING MOST OF WEEK-2, AND FOR NORTHERN AND CENTRAL
CALIFORNIA AT THE START OF THE PERIOD. THE PERSISTENCE OF ABOVE-NORMAL AND
POTENTIALLY HEAVY PRECIPITATION MAY LEAD TO FLOODING ACROSS PARTS OF THE
NORTHWEST. TIED TO THE EVOLUTION OF THE MID-LEVEL TROUGHING, SURFACE LOW
DEVELOPMENT IS FAVORED IN THE LEE OF THE ROCKIES, INCREASING CHANCES FOR HEAVY
PRECIPITATION ACROSS THE CENTRAL AND EASTERN CONTIGUOUS U.S. (CONUS) DURING THE
MIDDLE AND LATTER PORTIONS OF THE PERIOD. FOR PORTIONS OF THE EAST WHICH HAVE
SUSCEPTIBLE VEGETATION AND HAVE ALSO NOT EXPERIENCED THEIR FIRST FREEZE OR
FROST THIS SEASON, A SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES HAS BEEN
POSTED.
HAZARDS
MODERATE RISK OF HEAVY PRECIPITATION FOR A LARGE PORTION OF NORTHERN CALIFORNIA
NORTHWARD ACROSS SOUTHWESTERN OREGON, MON, OCT 27.
MODERATE RISK OF HIGH ELEVATION HEAVY SNOW OVER PORTIONS OF THE NORTHERN AND
CENTRAL SIERRA NEVADA, KLAMATH, AND SOUTHERN CASCADE MOUNTAINS, MON, OCT 27.
MODERATE RISK OF HEAVY PRECIPITATION OVER THE PACIFIC NORTHWEST, MON-SAT, OCT
27-NOV 1.
MODERATE RISK OF HIGH ELEVATION HEAVY SNOW OVER THE CASCADES, MON-FRI, OCT
27-31.
MODERATE RISK OF HIGH WINDS FOR WASHINGTON STATE, MON-WED, OCT 27-29.
MODERATE RISK OF HIGH WINDS FOR THE GENERAL VICINITY OF THE CENTRAL ROCKIES AND
CENTRAL PLAINS, MON-THU, OCT 27-30.
SLIGHT RISK OF HEAVY PRECIPITATION FOR MUCH OF NORTHERN AND CENTRAL CALIFORNIA
AND THE PACIFIC NORTHWEST, MON-SAT, OCT 27-NOV 1.
SLIGHT RISK OF HEAVY SNOW FOR THE SIERRA NEVADA, KLAMATH, AND CASCADE
MOUNTAINS, MON-SAT, OCT 27-NOV 1.
SLIGHT RISK OF HEAVY SNOW FOR PORTIONS OF THE NORTHERN INTERMOUNTAIN REGION,
AND NORTHERN AND CENTRAL ROCKIES, MON-TUE, OCT 27-28.
SLIGHT RISK OF HIGH WINDS FOR MUCH OF THE WESTERN, CENTRAL, AND NORTHERN CONUS,
MON-SAT, OCT 27-NOV 1.
SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES FOR PORTIONS OF THE GREAT LAKES,
OHIO AND TENNESSEE VALLEYS, APPALACHIANS, AND MID-ATLANTIC, MON, OCT 27.
SLIGHT RISK OF HEAVY PRECIPITATION FOR MUCH OF THE EASTERN HALF OF THE CONUS,
MON-SAT, OCT 27-NOV 1.
SLIGHT RISK OF HEAVY PRECIPITATION FOR SOUTHERN FLORIDA, WED-FRI, OCT 29-31.
SLIGHT RISK OF HIGH WINDS FOR THE SOUTHERN MAINLAND AND SOUTHEAST ALASKA,
MON-FRI, OCT 27-31.
FLOODING POSSIBLE ACROSS PARTS OF THE PACIFIC NORTHWEST AND NORTHERN CALIFORNIA.
DETAILED SUMMARY
FOR WEDNESDAY OCTOBER 22 - SUNDAY OCTOBER 26:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR MONDAY OCTOBER 27 - SUNDAY NOVEMBER 02: THE WEEK-2 HAZARDS PERSPECTIVE
REMAINS ON TRACK TODAY WITH MUCH OF THE OUTLOOK FOCUSING ON POTENTIAL
ATMOSPHERIC RIVER (AR) ACTIVITY OVER THE WESTERN CONUS, AND A LOW PRESSURE
SYSTEM PREDICTED OVER THE CENTRAL AND EASTERN CONUS, WITH BOTH PRODUCING
MULTIPLE WEATHER RELATED HAZARDS OF ELEVATED RISK. EARLY IN WEEK-2, A MID-LEVEL
TROUGH AXIS IS FORECAST NEAR THE WEST COAST, WITH THE PACIFIC JET DIRECTED AT
SOUTHERN OREGON AND NORTHERN CALIFORNIA. SLIGHT AND MODERATE RISKS OF HEAVY
PRECIPITATION AND HIGH ELEVATION HEAVY SNOW ARE POSTED FOR CENTRAL AND NORTHERN
PARTS OF THE WEST COAST STATES DURING DIFFERENT PORTIONS OF THE FORECAST
PERIOD. AS THIS BROAD AREA OF PACIFIC MOISTURE MOVES INLAND, THERE IS A SLIGHT
RISK OF HEAVY SNOW ACROSS THE NORTHERN AND CENTRAL ROCKIES, WITH THE BEST
CHANCE BEING ON OCT 27-28. THE AREAS OF PREDICTED HEAVY PRECIPITATION
(LOW-ELEVATION RAIN) AND MOUNTAIN SNOW ARE INDICATED BY THE 0Z GEFS AND 0Z
ECENS MODEL SOLUTIONS, THE GEFS AND ECENS INTEGRATED VAPOR TRANSPORT (IVT)
TOOLS, AND THE PROBABILISTIC EXTREME TOOLS (PETS). THE LATTER FAVORS SLIGHT
(20-40 PERCENT) AND MODERATE (40-60 PERCENT) CHANCES OF EXCEEDING THE
CLIMATOLOGICAL 85TH PERCENTILE AND 1-INCH (LIQUID EQUIVALENT). HIGH WINDS
(20-25 MPH OR GREATER) ARE FORECASTED BY THE 0Z ECENS AND 0Z GEFS MODEL
SOLUTIONS, AND THEIR RESPECTIVE PETS, TO INFLUENCE MOST OF THE WEST, RESULTING
IN SLIGHT AND MODERATE RISKS OF HIGH WINDS BEING POSTED TODAY. IN ADDITION, A
FLOOD RISK CONTINUES FOR THE PACIFIC NORTHWEST AND NORTHWESTERN CALIFORNIA,
ASSOCIATED WITH THIS AR-FUELLED PULSE OF MOISTURE. TODAY'S MODEL RUNS PREDICT
THE MOISTURE ASSOCIATED WITH THIS AR WILL REACH ITS MOST SOUTHERN EXTENT
(CENTRAL CALIFORNIA) AT THE BEGINNING OF THE WEEK-2 FORECAST PERIOD, FOLLOWED
BY A NORTHWARD SHIFT IN THE PACIFIC JET AND ACCOMPANYING PRECIPITATION INTO THE
PACIFIC NORTHWEST, WITH EASING IMPACTS ACROSS CALIFORNIA. AT THE SAME TIME, THE
TROUGH AXIS IS FORECAST TO SHIFT FARTHER INLAND, AND MID-LEVEL HEIGHTS BEGIN TO
RISE OVER THE SOUTHWESTERN CONUS.
SHORTWAVE ENERGY EMBEDDED WITHIN THE GENERAL WESTERLY FLOW MOVING OVER THE
ROCKIES IS FORECAST TO DIG SOUTHEASTWARD ACROSS THE GREAT PLAINS, ACCOMPANIED
BY BROAD LEESIDE TROUGHING. A SURFACE LOW PRESSURE CENTER INITIALLY OVER THE
VICINITY OF THE DAKOTAS IS PREDICTED TO TRANSLATE EASTWARD ACROSS THE UPPER
MIDWEST, GREAT LAKES REGION, AND NORTHEAST, ALONG WITH ITS ACCOMPANYING FRONTS.
THIS STORM SYSTEM WILL HAVE AMPLE MOISTURE TO WORK WITH, AS SURFACE HIGH
PRESSURE OFF THE EAST COAST BRINGS ATLANTIC AND GULF MOISTURE INTO THE MIDDLE
OF THE LOWER 48 STATES. THOUGH THE ECENS PET IS MORE ROBUST WITH ITS
PRECIPITATION FORECAST COMPARED TO THE GEFS PET, A SLIGHT RISK OF HEAVY
PRECIPITATION IS STILL FAVORED ACROSS MOST OF THE EASTERN HALF OF THE CONUS,
OCT 27-NOV 1. MUCH OF THIS REGION CAN EXPECT PRECIPITATION AMOUNTS RANGING FROM
0.5-INCH TO 1.5 INCHES. ADDITIONALLY, THIS STORM WARRANTS SLIGHT (OCT 27-NOV 1)
AND MODERATE (OCT 27-30) RISKS FOR HIGH WINDS OVER MUCH OF THE CENTRAL AND
NORTHERN CONUS (WIND SPEEDS GREATER THAN THE 85TH HISTORICAL PERCENTILE AND AT
LEAST 20-25 MPH).
A SLIGHT RISK AREA FOR HEAVY PRECIPITATION IS POSTED FOR SOUTHERN FLORIDA, OCT
29-31. ACCORDING TO MODEL GUIDANCE, A WIDESPREAD BLOB OF CLOUDINESS AND
PRECIPITATION IS EXPECTED TO DEVELOP OVER THE WESTERN CARIBBEAN SEA DURING THIS
TIME. THE NATIONAL HURRICANE CENTER IS MONITORING THE POTENTIAL FOR TROPICAL
CYCLOGENESIS IN THIS REGION. WHETHER OR NOT THIS LARGE, COHERENT REGION OF
MOISTURE DEVELOPS INTO A NAMED STORM (I.E., TROPICAL STORM OR HURRICANE),
MOISTURE IS PREDICTED TO STREAM OUTWARD FROM THE WESTERN CARIBBEAN SEA ACROSS
SOUTHERN FLORIDA AND OUT OVER THE WESTERN ATLANTIC.
EARLY IN WEEK-2, RESIDUAL COLD AIR IS EXPECTED TO BE IN PLACE ACROSS THE EAST.
THE PRIMARY IMPACT WOULD BE ITS EFFECT ON SUSCEPTIBLE VEGETATION THIS LATE IN
THE GROWING SEASON, IN AREAS THAT HAVE NOT YET EXPERIENCED THEIR FIRST FREEZE
OR FROST. THE ECENS AND GEFS PETS FORECAST MINIMUM TEMPERATURES LOWER THAN 40
DEGREES F ACROSS AREAS OF VULNERABLE VEGETATION AS DETERMINED BY THE MIDWESTERN
REGIONAL CLIMATE CENTER, WHICH AT THE VERY LEAST COULD PRODUCE AREAS OF
SCATTERED FROST. THEREFORE, A SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES
REMAINS POSTED FOR ONE MORE DAY, OCT 27, AND INCLUDES PARTS OF THE OHIO AND
TENNESSEE VALLEYS, APPALACHIANS, AND MID-ATLANTIC. LATER IN WEEK-2, ONCE THE
SIGNIFICANT STORM SYSTEM DESCRIBED EARLIER MOVES THROUGH THIS AREA,
NORTHWESTERLY WINDS WILL USHER IN MORE COLD AIR, WHICH MAY BRING NEAR-FREEZING
TEMPERATURES TO SOME LOCATIONS.
OVER ALASKA, A SLIGHT RISK OF HIGH WINDS REMAINS POSTED FOR THE SOUTHERN
MAINLAND AND SOUTHEAST ALASKA, BUT HAS BEEN EXTENDED THROUGH OCT 31. THIS IS
CONSISTENT WITH PET GUIDANCE, ESPECIALLY THE ECENS PET, WITH WIND SPEEDS
EXCEEDING THE 85TH HISTORICAL PERCENTILE, AND AT LEAST 40 MPH. THIS IS ALSO
REASONABLE GIVEN STRONG MID-LEVEL LOW PRESSURE OVER THE NORTHEASTERN PACIFIC.
FORECASTER: ANTHONY ARTUSA
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