413  
FXUS21 KWNC 011800  
PMDTHR  
US HAZARDS OUTLOOK  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD  
300 PM EDT NOVEMBER 01 2025  
 
SYNOPSIS: MID-LEVEL LOW PRESSURE FORECAST OVER THE NORTHEASTERN PACIFIC FAVORS  
AN INCREASED RISK OF HEAVY PRECIPITATION, HIGH ELEVATION SNOWFALL, AND HIGH  
WINDS OVER PORTIONS OF THE NORTHWESTERN CONTIGUOUS U.S. (CONUS) AND  
SOUTHEASTERN ALASKA DURING WEEK-2. ADDITIONAL SHORTWAVE ENERGY IS PREDICTED TO  
TRAVERSE THE NORTHERN TIER OF THE CONUS DURING THE PERIOD FAVORING ENHANCED  
CHANCES FOR HIGH WINDS AND HEAVY PRECIPITATION OVER THE NORTHEAST AND HIGH  
WINDS IN THE GREAT PLAINS. INCREASING MODEL SPREAD REDUCES FORECAST CONFIDENCE  
DURING THE SECOND HALF OF WEEK-2.  
 
HAZARDS  
 
SLIGHT RISK OF HEAVY PRECIPITATION ACROSS PORTIONS OF THE PACIFIC NORTHWEST AND  
NORTHERN CALIFORNIA, SUN-WED, NOV 9-12.  
 
SLIGHT RISK OF HEAVY PRECIPITATION ACROSS NEW ENGLAND, SUN, NOV 9.  
 
SLIGHT RISK OF HEAVY SNOW ACROSS PORTIONS OF THE CASCADES, SUN-WED, NOV 9-12.  
 
SLIGHT RISK OF HEAVY SNOW ACROSS PORTIONS OF THE NORTHERN ROCKIES, SUN-WED, NOV  
9-12.  
 
SLIGHT RISK OF HIGH WINDS ACROSS PORTIONS OF THE PACIFIC NORTHWEST AND NORTHERN  
CALIFORNIA, SUN-WED, NOV 9-12.  
 
SLIGHT RISK OF HIGH WINDS ACROSS PORTIONS OF THE GREAT LAKES, APPALACHIANS,  
MID-ATLANTIC, AND NORTHEAST, SUN-MON, NOV 9-10.  
 
SLIGHT RISK OF HIGH WINDS ACROSS PORTIONS OF THE PLAINS AND THE UPPER AND  
MIDDLE MISSISSIPPI VALLEY, SUN-TUE, NOV 9-11.  
 
DETAILED SUMMARY  
 
FOR TUESDAY NOVEMBER 04 - SATURDAY NOVEMBER 08:  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP  
 
FOR SUNDAY NOVEMBER 09 - SATURDAY NOVEMBER 15: THE 0Z GEFS, ECENS, AND CMCE  
MODELS REMAIN IN FAIR AGREEMENT REGARDING TROUGHING ACROSS THE NORTHEASTERN  
PACIFIC PERSISTING INTO WEEK-2. THE MODELS HAVE DIFFERENCES IN THE TIMING AND  
INTENSITY OF VARIOUS SHORTWAVE TROUGHS AND RIDGES ALONG THE WEST COAST. THIS  
INCREASES THE UNCERTAINTY OF THE STRENGTH AND TIMING OF ANY ENHANCED ONSHORE  
FLOW. NEVERTHELESS, TOOLS ARE CONSISTENT FOR PERIODS OF ENHANCED PRECIPITATION  
AND COASTAL HIGH WINDS THROUGH THE FIRST HALF OF WEEK-2. BOTH THE GEFS AND  
ECENS PROBABILISTIC EXTREMES TOOLS (PETS) INDICATE AT A 20-30 PERCENT CHANCE  
3-DAY PRECIPITATION TOTALS EXCEED THE 85TH CLIMATOLOGICAL PERCENTILE AND 1.5  
INCHES EARLY IN WEEK-2, WITH CHANCES DECREASING LATER IN THE PERIOD. THE ECENS  
INTEGRATED VAPOR TRANSPORT (IVT) TOOL CONTINUES TO INDICATE ENHANCED  
PROBABILITIES OF IVT VALUES EXCEEDING 250 KG/M/S THROUGH ABOUT DAY-11 (NOV 12),  
WHILE THE GEFS IVT HAS A WEAKER SIGNAL EARLY IN THE PERIOD BEFORE A RESURGENCE  
TOWARDS THE MIDDLE OF WEEK-2. THIS IS CONSISTENT WITH THE ECENS, AND ALSO THE  
CMCE, SHOWING A STRONGER RIDGE ACROSS THE INTERIOR WEST PERSISTING THROUGH THE  
MIDDLE OF THE PERIOD WITH A MORE PROGRESSIVE GEFS WITH A SHORTWAVE TROUGH AXIS  
OVER THE INTERIOR WEST EARLY IN WEEK-2. BASED ON THE ABOVE GUIDANCE, THERE IS  
ENOUGH SUPPORT TO MAINTAIN THE SLIGHT RISK FOR HEAVY PRECIPITATION ACROSS THE  
PACIFIC NORTHWEST AND NORTHERN CALIFORNIA THROUGH NOV 12. ANY HEAVY  
PRECIPITATION IS LIKELY TO LEAD TO INCREASED STREAMFLOWS AND POSSIBLY ISOLATED  
URBAN FLOODING WITHIN THE HIGHLIGHTED PRECIPITATION AREA.  
 
A SLIGHT RISK FOR HIGH WINDS IS ALSO POSTED OVER COASTAL AREAS OF THE PACIFIC  
NORTHWEST AND NORTHWESTERN CALIFORNIA, WHERE THE GEFS AND ECENS PETS DEPICT AT  
LEAST A 20 PERCENT CHANCE WIND SPEEDS EXCEED 25-MPH, ALONG WITH AN ENHANCED  
SIGNAL FOR WIND SPEEDS EXCEEDING 40-MPH JUST OFFSHORE. LASTLY, SLIGHT RISKS FOR  
HEAVY SNOW ARE POSTED ACROSS THE CASCADES AND NORTHERN ROCKIES. SIGNALS IN THE  
MODELS ARE MARGINAL, BUT 24-HOUR AMOUNTS EXCEEDING 4-INCHES ARE POSSIBLE, WITH  
HIGHER TOTALS FAVORED OVER THE NORTHERN CASCADES. THE AFOREMENTIONED WIND AND  
SNOW HAZARDS ARE VALID THROUGH NOV 12.  
 
THERE IS MORE UNCERTAINTY FURTHER EAST. THE TIMING AND PLACEMENT OF MULTIPLE  
SHORTWAVE TROUGHS OVER THE CENTRAL AND EASTERN CONUS IS DIFFERENT BETWEEN THE  
GEFS, ECENS, AND CMCE AND DIFFICULT TO PLACE. INITIALLY, AN AREA OF LOW  
PRESSURE IS FORECAST TO BE OVER OR NEAR THE NORTHEAST. THE ECENS IS A BIT  
SLOWER WITH THIS FEATURE MAINTAINING HIGH WINDS AND A HEAVY PRECIPITATION  
CHANCES OVER THE GREAT LAKES AND NORTHEAST UNTIL DAY 8. MEANWHILE, MOST OF THE  
GEFS SIGNAL HAS ALREADY MOVED OFFSHORE BY THE START OF WEEK-2. IN DEFERENCE TO  
CONTINUITY, HAVE MAINTAINED A SLIGHT RISK OF HEAVY PRECIPITATION OVER NEW  
ENGLAND FOR NOV 9. A BROADER SLIGHT RISK OF HIGH WINDS IS FORECAST FOR THE  
GREAT LAKES AND NORTHEAST FOR NOV 9-10 AS WINDS MAY REMAIN ELEVATED FOLLOWING A  
FRONTAL PASSAGE.  
 
MEANWHILE, THE GEFS FAVORS BRINGING ANOTHER SHORTWAVE TROUGH INTO THE ROCKIES  
AND SPINNING UP AN AREA OF LOW PRESSURE IN THE LEE OF THE ROCKIES. THE GEFS PET  
AND RAW ENSEMBLE GUIDANCE SUPPORT A RELATIVELY BROAD SLIGHT RISK OF HIGH WINDS  
ACROSS MUCH OF THE PLAINS. THE ECENS AND THE ECENS AI RAW GUIDANCE IS NOT AS ON  
BOARD WITH THIS SOLUTION AS THE MEAN ENSEMBLE GUIDANCE DOES NOT SUPPORT A  
SHORTWAVE TROUGH EARLY IN THE PERIOD. HOWEVER, THERE IS SOME SUPPORT FROM THE  
ECENS PET FOR WIND SPEEDS EXCEEDING THE 85TH PERCENTILE. THEREFORE, A SLIGHT  
RISK OF HIGH WINDS IS POSTED FOR NOV 9-11.  
 
ACROSS ALASKA, PERIODS OF HIGH WINDS AND LOCALLY HEAVY PRECIPITATION ARE  
POSSIBLE OVER THE SOUTHEAST ASSOCIATED WITH ANOMALOUS MID-LEVEL TROUGHING OVER  
THE NORTHEASTERN PACIFIC AND BERING SEA. HOWEVER PETS SHOW PRECIPITATION  
AMOUNTS AND WIND SPEEDS LIKELY REMAINING BELOW HAZARD THRESHOLDS.  
 
FORECASTER: RYAN BOLT  
 

 
 
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