075
FXUS21 KWNC 091923
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EST FEBRUARY 09 2026
SYNOPSIS: A MAJOR PATTERN CHANGE IS FORECAST OVER THE WEST LATER THIS WEEK AS A
STRONG AREA OF MID-LEVEL LOW PRESSURE DEVELOPS ALONG THE WEST COAST. FOLLOWING
A DRIER-THAN-NORMAL JANUARY AND START TO FEBRUARY, A TRANSITION TO A MUCH
WETTER, COLDER PATTERN IS LIKELY FOR THE WEST BY THIS WEEKEND. EARLY IN WEEK-2,
THE STRONG AREA OF MID-LEVEL LOW PRESSURE WILL LEAD TO AN INCREASED RISK OF
HEAVY PRECIPITATION, HIGH ELEVATION HEAVY SNOW, AND HIGH WINDS TO THE PACIFIC
NORTHWEST, CALIFORNIA, AND INTERIOR WEST. ENHANCED ONSHORE FLOW IS EXPECTED TO
SHIFT BACK TO THE NORTH TOWARDS THE PACIFIC NORTHWEST LATER IN WEEK-2. THERE IS
ALSO AN ELEVATED WINTER STORM RISK FROM THE NORTHERN TO CENTRAL GREAT PLAINS
NORTHEAST TO THE UPPER MISSISSIPPI VALLEY FROM FEB 17 TO 20.
HAZARDS
HIGH RISK OF HEAVY PRECIPITATION FOR COASTAL CALIFORNIA FROM THE BAY AREA
SOUTHWARD TO SOUTHERN CALIFORNIA, TUE, FEB 17.
HIGH RISK OF HEAVY SNOW FOR THE SIERRA NEVADA MOUNTAINS, TUE-WED, FEB 17-18.
MODERATE RISK OF HEAVY PRECIPITATION FOR COASTAL CALIFORNIA AND SOUTHWESTERN
OREGON, TUE-WED, FEB 17-18.
MODERATE RISK OF HEAVY SNOW FOR THE SIERRA NEVADA, KLAMATH MOUNTAINS, AND
SOUTHERN CASCADES, TUE-THU, FEB 17-19.
MODERATE RISK OF HEAVY SNOW FOR SOUTHWESTERN UTAH AND THE MOGOLLON RIM OF
ARIZONA, TUE-WED, FEB 17-18.
MODERATE RISK OF HIGH WINDS FOR THE DESERT SOUTHWEST, FOUR CORNERS, AND CENTRAL
TO SOUTHERN HIGH PLAINS, TUE-THU, FEB 17-19.
SLIGHT RISK OF HEAVY PRECIPITATION FOR THE PACIFIC NORTHWEST, CALIFORNIA, AND
PARTS OF THE SOUTHWEST, TUE-MON, FEB 17-23.
SLIGHT RISK OF HEAVY SNOW FOR THE CASCADES, KLAMATH, AND SIERRA NEVADA
MOUNTAINS, TUE-MON, FEB 17-23.
SLIGHT RISK OF HEAVY SNOW FOR THE INTERIOR WEST, TUE-FRI, FEB 17-20.
SLIGHT RISK OF HIGH WINDS FROM THE WEST COAST TO THE GREAT PLAINS, TUE-THU, FEB
17-19.
SLIGHT RISK OF HEAVY SNOW FOR THE CENTRAL TO NORTHERN PLAINS, UPPER MISSISSIPPI
VALLEY, AND GREAT LAKES, TUE-FRI, FEB 17-20.
SLIGHT RISK OF MUCH BELOW-NORMAL TEMPERATURES FOR SOUTHEASTERN ALASKA, TUE-MON,
FEB 17-23.
SLIGHT RISK OF MUCH BELOW-NORMAL TEMPERATURES FOR SOUTHWESTERN ALASKA, FRI-MON,
FEB 20-23.
FLOODING POSSIBLE FROM THE BAY AREA TO SOUTHERN CALIFORNIA.
DETAILED SUMMARY
FOR THURSDAY FEBRUARY 12 - MONDAY FEBRUARY 16:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR TUESDAY FEBRUARY 17 - MONDAY FEBRUARY 23: THE GEFS, ECENS, AND CMCE ARE
VERY CONSISTENT AND IN GOOD AGREEMENT THAT A 500-HPA TROUGH AMPLIFIES ALONG THE
WEST COAST THIS WEEKEND. THE PACIFIC NORTH AMERICAN (PNA) INDEX IS FORECAST TO
RAPIDLY BECOME NEGATIVE AND PERSIST IN THIS NEGATIVE PHASE THROUGH LATE
FEBRUARY. BY THE BEGINNING OF WEEK-2 (FEB 17), A HIGHLY AMPLIFIED 500-HPA
TROUGH (HEIGHT ANOMALIES OF -200 METERS) IS FORECAST TO EXTEND SOUTH TO
CALIFORNIA. THE ECENS REMAINS THE WETTEST MODEL SOLUTION AND DEPICTS GREATER
THAN A 20 PERCENT CHANCE THAT PRECIPITATION AMOUNTS EXCEED 2 INCHES ACROSS
SOUTHERN CALIFORNIA EARLY IN WEEK-2. DUE TO THIS CONSISTENT MODEL SIGNAL, A
HIGH RISK OF HEAVY PRECIPITATION CONTINUES FOR SOUTHERN CALIFORNIA ON FEB 17.
BASED ON 24-HOUR PRECIPITATION AMOUNTS FROM THE ECENS, GEFS, AND CMCE ALONG THE
GEFS PROBABILISTIC EXTREMES TOOL (PET), A MODERATE RISK OF HEAVY PRECIPITATION
IS VALID THROUGH FEB 18 AND COVERS THE ENTIRE COASTAL AREA OF CALIFORNIA AND
EXTENDS NORTH TO SOUTHWESTERN OREGON. SINCE THERE IS LIKELY TO BE MULTIPLE DAYS
OF HEAVY PRECIPITATION FROM THIS WEEKEND INTO EARLY NEXT WEEK, A FLOODING
HAZARD IS DESIGNATED FROM THE BAY AREA SOUTH TO SOUTHERN CALIFORNIA WHERE URBAN
AND/OR SMALL STREAM FLOODING MAY OCCUR. THE GEFS PET SUPPORTS A SLIGHT RISK OF
HEAVY PRECIPITATION (AT LEAST A 20 PERCENT CHANCE OF 3-DAY AMOUNTS EXCEEDING 1
INCH) THROUGHOUT CALIFORNIA, THE DESERT SOUTHWEST, AND PACIFIC NORTHWEST.
HOWEVER MODEL GUIDANCE, INCLUDING THE INTEGRATED VAPOR TRANSPORT TOOLS,
INDICATE THAT THE GREATEST RISK OF HEAVY PRECIPITATION SHIFTS TOWARDS NORTHERN
CALIFORNIA AND THE PACIFIC NORTHWEST BEGINNING ON FEB 20.
THE DEEP MID-LEVEL TROUGH IS LIKELY TO BRING HEAVY SNOW TO THE SIERRA NEVADA
MOUNTAINS WHERE THE ECENS AND GEFS DEPICT MORE THAN A 60 PERCENT CHANCE THAT
ACCUMULATIONS EXCEED ONE FOOT EARLY IN WEEK-2. BASED ON 24-HOUR PRECIPITATION
AMOUNTS FROM THESE ENSEMBLE MEAN SOLUTIONS, A HIGH RISK OF HEAVY SNOW IS VALID
ON FEB 17 AND 18. THE MODERATE RISK OF HEAVY SNOW GOES THROUGH FEB 19 AND ALSO
INCLUDES THE KLAMATH MOUNTAINS AND SOUTHERN CASCADES. SINCE BOTH THE ECENS AND
GEFS FAVOR A 500-HPA TROUGH PERSISTING OVER THE NORTHEASTERN PACIFIC THROUGH
THE END OF WEEK-2, A SLIGHT RISK OF HEAVY SNOW IS VALID FROM FEB 17-23 AND
EXTENDS FROM THE CASCADES SOUTH TO THE SIERRA NEVADA MOUNTAINS. DUE TO
ANOMALOUS MID-LEVEL TROUGH ALONG WITH SUPPORT FROM THE GEFS SNOW WATER
EQUIVALENT (SWE) TOOL, A MODERATE RISK OF HEAVY SNOW IS POSTED FOR THE MOGOLLON
RIM OF ARIZONA AND SOUTHWESTERN UTAH. A SLIGHT RISK OF HEAVY SNOW AT THE HIGHER
ELEVATIONS OF THE INTERIOR WEST WAS DISCONTINUED AFTER FEB 20TH AS 500-HPA
HEIGHTS ARE FORECAST TO RISE SLIGHTLY. THE MUCH SNOWIER LATTER HALF OF FEBRUARY
WILL BE WELCOMED ACROSS THE WEST AS SWE IS CURRENTLY BELOW 50% OF AVERAGE FOR
MUCH OF THE PACIFIC NORTHWEST, GREAT BASIN, AND CALIFORNIA.
THE HIGH AMPLITUDE 500-HPA TROUGH ALSO SUPPORTS A SLIGHT RISK OF HIGH WINDS
WITH A LARGE SPATIAL AREA FROM THE WEST COAST TO THE GREAT PLAINS. A MODERATE
RISK OF HIGH WINDS IS POSTED FOR THE DESERT SOUTHWEST, FOUR CORNERS REGION, AND
CENTRAL TO SOUTHERN HIGH PLAINS WHERE THE ECENS DEPICTS MORE THAN A 40% CHANCE
THAT WINDS GUST ABOVE 40MPH. MODEL SOLUTIONS FAVOR LEESIDE CYCLOGENESIS ACROSS
EASTERN COLORADO ON FEB 18 WHICH WOULD BRING GUSTY WINDS AND ELEVATE WILDFIRE
DANGER FOR THE CENTRAL AND SOUTHERN HIGH PLAINS.
THE LONGWAVE PATTERN WOULD FAVOR MULTIPLE LOW PRESSURE SYSTEMS TO DEVELOP
ACROSS THE HIGH PLAINS WITH A SUBSEQUENT NORTHEASTWARD TRACK TO THE UPPER
MIDWEST DURING MID TO LATE FEBRUARY. ON FEB 17 AND 18 AND THEN A FEW DAYS
LATER, THE ECENS AND GEFS DEPICT LOW PRESSURE SYSTEMS TRACKING THROUGH THE
UPPER MISSISSIPPI VALLEY. TO THE NORTHWEST OF ANY LOW PRESSURE TRACK, THERE IS
AN ELEVATED RISK OF A WINTER STORM ACROSS THE NORTHERN AND CENTRAL PLAINS INTO
THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES. BASED ON PATTERN RECOGNITION AND
THE GEFS SWE TOOL (20-40% CHANCE OF 3-DAY AMOUNTS TO EXCEED THE 85TH PERCENTILE
AND 0.5 INCH, LIQUID EQUIVALENT), A SLIGHT RISK OF HEAVY SNOW IS POSTED FROM
THE NORTHERN AND CENTRAL GREAT PLAINS NORTHEAST TO THE UPPER MISSISSIPPI VALLEY
AND GREAT LAKES. THE INITIAL LOW AT THE BEGINNING OF WEEK-2 IS EXPECTED TO TAKE
A MORE NORTHERN TRACK THROUGH MINNESOTA AND NORTHERN WISCONSIN, WHILE ANY
SECONDARY LOW LATER IN WEEK-2 WOULD PROBABLY SHIFT MORE SOUTH ACROSS NEBRASKA,
IOWA, AND SOUTHERN WISCONSIN.
DUE TO THE AMPLIFIED 500-HPA RIDGE TO THE WEST OF THE BERING STRAIT AND
ANOMALOUS NORTHERLY FLOW, BELOW-NORMAL TEMPERATURES ARE LIKELY THROUGHOUT
ALASKA FROM FEB 17-23. BASED ON THE GEFS AND ECENS PETS (> 20% CHANCE OF
MINIMUM TEMPERATURES IN THE LOWEST 15TH PERCENTILE), A SLIGHT RISK OF MUCH
BELOW-NORMAL TEMPERATURES IS POSTED FOR SOUTHEASTERN ALASKA DURING THE ENTIRETY
OF WEEK-2. GAP WINDS WOULD RESULT IN DANGEROUSLY COLD WIND CHILL VALUES. THE
ECENS DEPICTS THE AMPLIFIED 500-HPA RIDGE STRENGTHENING AND SHIFTING WEST TO
EASTERN SIBERIA LATER IN WEEK-2 WHICH WOULD FAVOR MUCH BELOW-NORMAL
TEMPERATURES TO EXPAND WEST INTO SOUTHWESTERN ALASKA. THEREFORE, A SLIGHT RISK
OF MUCH BELOW-NORMAL TEMPERATURES IS POSTED FOR THAT AREA BEGINNING ON FEB 20.
OVER HAWAII, THE FORECAST PATTERN CONTINUES TO BE FAVORABLE FOR KONA LOW
DEVELOPMENT INTO THE LATTER HALF OF FEBRUARY. THE GEFS PET DEPICTS A 20 TO 40
PERCENT CHANCE THAT 3-DAY PRECIPITATION AMOUNTS EXCEED THE 85TH PERCENTILE FOR
THE ENTIRE ISLAND CHAIN FROM FEB 17-23.
FORECASTER: BRAD PUGH
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