365
FXUS61 KPBZ 121028
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
528 AM EST FRI DEC 12 2025
SYNOPSIS
DRY CONDITIONS RESUME TODAY AS HIGH PRESSURE BRIEFLY TAKES
CONTROL. WIDESPREAD SNOW RETURNS SATURDAY WITH THE HIGHEST
ACCUMULATION RATES DURING THE EVENING AND OVERNIGHT INTO SUNDAY,
ESPECIALLY ALONG AND SOUTH OF THE INTERSTATE 70 CORRIDOR. BELOW
NORMAL TEMPERATURES CONTINUE INTO NEXT WEEK.
NEAR TERM /THROUGH TONIGHT/
KEY MESSAGES:
- MAINLY DRY TODAY
- CONTINUED BELOW NORMAL TEMPERATURES
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LATEST RADAR IMAGERY SHOWS DIMINISHING RETURNS UNDER INCREASING
SUBSIDENCE AS RIDGING MOVES IN ACROSS THE REGION. WITH THAT AND
AFTER REVIEW OF LATEST SURFACE OBSERVATIONS AND AREA WEBCAMS,
HAVE CANCELLED THE WINTER WEATHER ADVISORY FOR
VENANGO/CLARION/FOREST/JEFFERSON. WHILE SNOW WILL LIKELY STILL
BE OBSERVED, ANY FURTHER ACCUMULATION WILL BE MINIMAL AS THE
BOUNDARY LAYER FAILS TO EXTEND THROUGH THE DGZ BASED ON LATEST
SOUNDINGS. A SHORTWAVE WILL CROSS THE LOWER GREAT LAKES
OVERNIGHT INTO EARLY SATURDAY, RESULTING IN LIGHT SNOW CHANCES
BUT MINIMAL ACCUMULATION.
SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/
KEY MESSAGES:
- DISTURBANCE FORECAST TO PRODUCE IMPACTFUL SNOW SOUTH OF I-70.
- BELOW NORMAL TEMPERATURES PERSIST.
- WINTER STORM WATCH: SATURDAY AFTERNOON TO SUNDAY AFTERNOON.
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THE MAIN CONCERN WILL BE A DISTURBANCE ARRIVING SATURDAY AFTERNOON.
CURRENTLY, THE LOW IS WITHIN A PROGRESSIVE UPPER-LEVEL TROUGH AND
WILL QUICKLY MOVE FROM CENTRAL CANADA SOUTHEASTWARD INTO THE OHIO
VALLEY BY SATURDAY EVENING. THE MAIN BAND SEEMS TO LINE ALONG AND
JUST SOUTH OF THE I-70 CORRIDOR. THIS AREA HAS A 70%-80% PROBABILITY
FOR 24 HOUR SNOWFALL ACCUMULATIONS GREATER THAN 5 INCHES, WITH
WARNING CRITERIA AMOUNTS NEAR 50%-60%. DUE TO THE COLD/DRY AIR, THE
SNOW IS EXPECTED TO BE DRY AND FLUFFY. THE MAIN IMPACT WINDOW FAVORS
SATURDAY EVENING INTO SUNDAY MORNING WITH THE POTENTIAL FOR LONGER
DURATION IN THE HIGHER TERRAIN DUE TO POST-TROUGH ENVIRONMENT (SEE
SECTION BELOW).
VARIATIONS EXIST IN THE NORTH TO SOUTH ORIENTATION OF THE AXIS OF
HEAVIER SNOW (LIKELY TO BE AIDED BY A STRENGTHENING MID-LEVEL JET).
A WINTER STORM WATCH WAS ISSUED FOR THE POTENTIAL OF IMPACTFUL
SNOWFALL ACCUMULATIONS. AREAS OUTSIDE THE WATCH COULD STILL SEE
ADVISORY-LEVEL CRITERIA SNOW WHICH MAY NECESSITATE FUTURE HEADLINES
PENDING INCREASED CONFIDENCE OF AREAL COVERAGE.
LONG TERM /SUNDAY THROUGH THURSDAY/
KEY MESSAGES:
- MUCH COLDER WITH SNOW CHANCES INTO MONDAY MORNING
- WARMER WITH RAIN RETURNING FOR THE SECOND HALF OF THE WEEK
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MODEL ENSEMBLES INDICATE A DEEP UPPER TROUGH WILL CROSS THE REGION
SUNDAY FOLLOWING THE DISTURBANCE SATURDAY. THIS COMBINE WITH COLD
WNW/NW FLOW ACROSS THE GREAT LAKES, WILL MAINTAIN SNOW CHANCES
ACROSS THE REGION (MAINLY LAKE EFFECT SNOW SHOWERS). MODEL ENSEMBLE
850 MB TEMPS DROP TO -17C TO -19C THROUGH THE DAY, WITH HIGH
TEMPERATURES ONLY REACHING BETWEEN 15F TO 20F RANGE. WITH WIND GUSTS
UP TO 30-35 MPH DURING THE DAY, WIND CHILL IS EXPECTED TO BE IN THE
SINGLE DIGITS TO AS LOW AS -15F IN THE HIGHER TERRAIN OF WV. SUNDAY
NIGHT'S LOW TEMPERATURES ARE EXPECTED TO BE IN THE TEENS AS THE WIND
EASES.
SNOW CHANCES SHOULD TAPER OFF MONDAY AS LOW-LEVEL RIDGING BUILDS IN,
AND WARM ADVECTION BEGINS. DRY WEATHER IS THEN EXPECTED THROUGH MID-
WEEK AS THE FLOW ALOFT BECOMES ZONAL, AND TEMPERATURES MODERATE. A
TROUGH EMBEDDED IN THE ZONAL FLOW IS PROGGED TO APPROACH AND CROSS
THE REGION WEDNESDAY NIGHT THROUGH THURSDAY NIGHT, WITH
PRECIPITATION CHANCES RETURNING. MAINLY RAIN IS EXPECTED, WITH 850
MB TEMPERATURES PROGGED AT +3 TO +6 DEG C.
AVIATION /09Z FRIDAY THROUGH TUESDAY/
KEY MESSAGES:
- PATCHY MVFR IN SCATTERED SNOW NORTH OF KPIT OVERNIGHT.
- POSSIBLE HIGH MVFR, BUT LARGELY VFR OVER THE COURSE OF THE
DAY
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SNOW SHOWERS WILL DIMINISH OVERNIGHT UNDER INCREASING
SUBSIDENCE AND SFC HIGH PRESSURE APPROACHING FROM THE WEST.
CONTINUED COLD- AIR ADVECTION, HOWEVER, WILL MAINTAIN AN
ENVIRONMENT FAVORABLE FOR STRATOCU THRU MUCH OF TONIGHT, WITH
OCCASIONAL MVFR CIGS POSSIBLE.
RELATIVELY LIGHT WINDS EXPECTED THROUGH THE DAY WITH CROSSING
HIGH PRESSURE AND A RELAXED PRESSURE GRADIENT
OUTLOOK...
AN ADVANCING COLD FRONT WILL CONTINUE POTENTIAL FOR FLIGHT
RESTRICTIONS AMID SNOW SHOWERS LATER ON SATURDAY, WITH
WIDESPREAD RESTRICTIONS AND ACCUMULATING SNOWFALL SAT NIGHT INTO
SUN MORNING AT MOST TERMINALS AS A STRONG UPPER-LEVEL TROUGH
CROSSES THE UPPER OHIO VALLEY. SCATTERED SNOW SHOWERS WITH
OCCASIONAL RESTRICTIONS ARE POSSIBLE MON AMID COLD NWLY FLOW.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY
AFTERNOON FOR PAZ029-031-073>076.
OH...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY
AFTERNOON FOR OHZ059-068-069.
WV...WINTER STORM WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY
AFTERNOON FOR WVZ003-004-012-021-509>514.
SYNOPSIS...88
NEAR TERM...88
SHORT TERM...FRAZIER/LUPO
LONG TERM...WM/LUPO
AVIATION...88
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