557
FXUS21 KWNC 161818
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT OCTOBER 16 2026
SYNOPSIS: LATER NEXT WEEK, MID-LEVEL LOW PRESSURE ALOFT AND AT THE SURFACE IS
FAVORED OVER THE CENTRAL AND SOUTHEASTERN CONTIGUOUS U.S. (CONUS). ALTHOUGH
THESE FEATURES ARE FORECAST TO WEAKEN HEADING INTO WEEK-2, THERE IS A LINGERING
RISK OF HEAVY PRECIPITATION OVER THE SOUTHERN PLAINS, ALONG WITH AN INCREASED
RISK OF HIGH WINDS OVER THE LOWER EASTERN SEABOARD EARLY IN WEEK-2. TOWARDS
THE MIDDLE OF WEEK-2, THE POTENTIAL RETURN OF MID-LEVEL LOW PRESSURE OFFSHORE
OF THE WEST COAST SUPPORTS AN INCREASED RISK OF HEAVY PRECIPITATION AND OTHER
WEATHER RELATED HAZARDS ACROSS THE WESTERN CONUS, HOWEVER MODEL DISAGREEMENT IN
REGARDS TO TIMING, COVERAGE AND STRENGTH OF THESE RISKS PRECLUDES ANY
CORRESPONDING HAZARDS AT THIS TIME.
HAZARDS
SLIGHT RISK OF HEAVY PRECIPITATION FOR PARTS OF THE SOUTHERN PLAINS, SAT, OCT
24.
SLIGHT RISK OF HIGH WINDS FOR PORTIONS OF THE MID-ATLANTIC AND THE SOUTHEAST,
SAT-MON, OCT 24-26.
DETAILED SUMMARY
FOR MONDAY OCTOBER 19 - FRIDAY OCTOBER 23:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
FOR SATURDAY OCTOBER 24 - FRIDAY OCTOBER 30: BY LATE NEXT WEEK, DYNAMICAL MODEL
500-HPA HEIGHT FORECASTS FROM THE ECENS AND GEFS ARE IN GOOD AGREEMENT
FEATURING AN AMPLIFIED RIDGE AXIS OVERSPREADING MUCH OF THE PLAINS AND
MISSISSIPPI VALLEY, BOOKENDED BY A PAIR OF MEAN TROUGHS WITH ONE LOCATED OVER
THE SOUTHWESTERN CONUS, AND THE OTHER DIGGING FAR SOUTH INTO FLORIDA AND THE
TROPICAL GULF AND CARIBBEAN. AS THE AMPLIFIED RIDGE CENTER PROGRESSES EASTWARD
ACROSS SOUTH-CENTRAL CANADA EARLY IN WEEK-2, MUCH OF THE ANOMALOUS TROUGHING IS
FAVORED TO WEAKEN, HOWEVER, THE ACCOMPANYING MEAN SURFACE LOW IN THE LEE OF
ROCKIES, AND ANOTHER SURFACE SYSTEM SITUATED OFFSHORE OF THE LOWER EASTERN
SEABOARD MAY BRING A LINGERING RISK OF UNSETTLED WEATHER OVER THESE TWO PARTS
OF THE COUNTRY EARLY IN THE PERIOD. LATER IN WEEK-2, THERE ARE SOME ENSEMBLE
INDICATIONS OF MID-LEVEL TROUGHING TO RELOAD OVER THE EASTERN PACIFIC, WHICH
COULD BRING A RENEWED RISK OF HEAVY PRECIPITATION OVER PARTS OF THE WESTERN
CONUS. DOWNSTREAM, MODELS GENERALLY MAINTAIN A POSITIVELY TILTED ORIENTATION OF
THE RIDGE AXIS, ALLOWING FOR A WEAKNESS IN THE HEIGHT FIELDS AND CYCLONIC FLOW
TO PERSIST ACROSS THE SOUTHEASTERN CONUS, SUPPORTIVE OF CONTINUED UNSETTLED
WEATHER ACROSS THE REGION.
ACROSS THE GREAT PLAINS, BOTH THE GEFS AND ECENS BOTH HIGHLIGHT THE MEAN
SURFACE LOW ACROSS THE CENTRAL AND NORTHERN HIGH PLAINS ON DAY 8 (OCT 24).
ALTHOUGH THIS SURFACE LOW IS EXPECTED TO SWIFTLY FILL-IN BY DAY 9 (OCT 25),
CONTINUED FRONTAL FORCING FURTHER SOUTH IS EXPECTED TO PROMOTE ENHANCED AND
POSSIBLY HEAVY PRECIPITATION ACROSS THE SOUTHERN PLAINS. BASED ON CONTINUED
SUPPORT IN BOTH RAW AND CALIBRATED PROBABILISTIC EXTREME TOOLS (PETS), A SLIGHT
RISK OF HEAVY PRECIPITATION REMAINS POSTED AND VALID THROUGH OCT 24 WITH ITS
COVERAGE SLIGHTLY SHIFTED WESTWARD WHERE THERE ARE INCREASED CHANCES FOR 3-DAY
AMOUNTS EXCEEDING AN INCH RELATIVE TO YESTERDAY. TIED TO THE WEAKENING OF BOTH
THE TROUGHING ALOFT AND THE SURFACE LOW, THERE IS A LESSENED RISK OF HEAVY HIGH
ELEVATION SNOW OVER THE INTERIOR WEST AND GUSTY WINDS OVER THE CENTRAL AND
NORTHERN PLAINS. WHILE THE ECENS MAINTAINS SOME RESIDUAL CYCLONIC FLOW OVER THE
INTERIOR WEST, THE GEFS AND CANADIAN ENSEMBLES ARE MORE ZONAL AND QUICKER TO
BRING CALMER AND DRIER CONDITIONS BY THE OUTSET OF THE OUTLOOK PERIOD, WHICH IS
SUPPORTED IN THE GEFS BASED SNOW WATER EQUIVALENT (SWE) AND WIND PETS.
THEREFORE, BOTH THE SLIGHT RISK OF HEAVY SNOW OVER THE ROCKIES, AND SLIGHT RISK
OF HIGH WINDS OVER THE PLAINS ARE REMOVED IN THE UPDATED OUTLOOK.
DOWNSTREAM, AN AREA OF ENHANCED PRECIPITATION AND ELEVATED WINDS ARE FAVORED
ASSOCIATED WITH AN AREA OF SURFACE LOW PRESSURE OVER THE WESTERN ATLANTIC WITH
HIGH PRESSURE TO THE NORTH OVER THE NORTHEAST NEXT WEEKEND. WHILE ANY WESTWARD
PROTRUSION OF A QUASI-STALLED FRONTAL ACTIVITY WOULD BRING ENHANCED
PRECIPITATION INTO COASTAL PORTIONS OF THE LOWER EASTERN SEABOARD, THE
UNCALIBRATED GEFS AND ECENS MAINTAIN THE HEAVIEST DAILY PRECIPITATION AMOUNTS
OFFSHORE EARLY IN WEEK-2, PRECLUDING ANY CORRESPONDING PRECIPITATION HAZARD.
GIVEN THE SYNOPTIC SETUP, HOWEVER, THERE IS THE POTENTIAL FOR STRENGTHENING
SURFACE PRESSURE GRADIENTS AND PERIODS OF ELEVATED WINDS, WHICH IS SUPPORTED BY
BOTH THE GEFS AND ECENS PETS DEPICTING INCREASED CHANCES FOR WIND SPEEDS
EXCEEDING THE 85TH PERCENTILE. THEREFORE A SLIGHT RISK OF HIGH WINDS IS POSTED
FOR THE LOWER EASTERN SEABOARD FOR OCT 24-26.
TOWARDS THE MIDDLE OF WEEK-2, A RELOADING TROUGH OFFSHORE OF THE WEST COAST IS
DEPICTED IN THE ENSEMBLES, BUT THE GEFS AND ECENS DIFFER IN REGARDS TO THE
STRENGTH, SHAPE, AND DEVELOPMENT TIMING OF THIS ANOMALOUS MID-LEVEL FEATURE. IN
RESPONSE TO MORE PACIFIC FLOW, PETS SHOW AN UPTICK IN SIGNALS IN PERCENTILE
SPACE (AT THE 85TH CLIMATOLOGICAL THRESHOLD), WITH THE GEFS FOCUSING THESE
SIGNALS OVER THE LOWER FOUR CORNERS AND THE ECENS FEATURING A MORE EXPANSIVE
COVERAGE INTO THE WEST COAST, INCLUDING SUPPORT FOR 3-DAY AMOUNTS EXCEEDING AN
INCH OVER NORTHERN CALIFORNIA. IN LIGHT OF THESE DIFFERENCES, DRIER SIGNALS IN
THE UNCALIBRATED TOOLS, AND GENERAL UNCERTAINTY AT THIS LEAD, NO HAZARDS ARE
ISSUED BUT A HEAVY PRECIPITATION POTENTIAL, AS WELL AS OTHER WEATHER RELATED
HAZARDS ASSOCIATED WITH A RELOADING TROUGH OVER THE WESTERN CONUS WILL CONTINUE
TO BE MONITORED IN UPCOMING OUTLOOKS.
UPSTREAM OF AN ANOMALOUS RIDGE AXIS EXTENDING INTO THE YUKON, SOUTHWESTERLY
FLOW AND A MEAN SURFACE LOW FAVORED TO THE NORTH OF THE ALEUTIANS SUPPORTS
ABOVE NORMAL PRECIPITATION FOR MUCH OF THE SOUTHERN MAINLAND AND THE SOUTHEAST
EARLY IN THE PERIOD. GOOD AGREEMENT EXISTS BETWEEN THE GEFS AND ECENS PETS
FEATURING INCREASED CHANCES FOR 3-DAY PRECIPITATION AMOUNTS AND WIND SPEEDS
EXCEEDING THE 85TH PERCENTILE ASSOCIATED WITH THIS PATTERN, HOWEVER ACTUAL
AMOUNTS AND WIND SPEEDS ARE NOT EXPECTED TO REACH HAZARD THRESHOLDS, RESULTING
IN NO CORRESPONDING HAZARDS AT THIS TIME.
FORECASTER: NICK NOVELLA
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