056
FXUS61 KPBZ 120545
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1245 AM EST MON JAN 12 2026
WHAT HAS CHANGED
POTENTIAL FOR SNOW HAS INCREASED LATE WEDNESDAY INTO THURSDAY
AFTER THE PASSAGE OF A COLD FRONT. A STRONG UPPER TROUGH AND A
DEVELOPING SURFACE WAVE WILL LIKELY HAVE AN IMPACT ON AMOUNTS,
BUT UNCERTAINTY REMAINS.
KEY MESSAGES
1) DRY TODAY AND TUESDAY
2) RAIN WEDNESDAY
3) RAIN CHANGING TO SNOW LATE WEDNESDAY, WITH SNOW LIKELY
OVERNIGHT WEDNESDAY AND THURSDAY
4) COLD WITH PERIODIC SNOW CHANCES LATE WEEK THROUGH NEXT
WEEKEND
DISCUSSION
KEY MESSAGE 1...
WEAK LOW LEVEL RIDGING WILL BUILD ACROSS THE REGION TODAY, WITH
DRY WEATHER EXPECTED. THE STRATOCU CLOUD LAYER IS EXPECTED TO
GRADUALLY ERODE FROM SW-NE WITH INCREASING SUBSIDENCE AND A
BACKING BOUNDARY LAYER FLOW.
DRY AND WARMER WEATHER IS EXPECTED TUESDAY, THOUGH CLOUD COVER
WILL INCREASE IN WARM ADVECTION AS A SHORTWAVE TROUGH, AND ITS
ASSOCIATED SURFACE COLD FRONT, APPROACH FROM THE UPPER MIDWEST.
KEY MESSAGE 2...
A DEEPENING TROUGH AND ASSOCIATED SURFACE COLD FRONT IS PROGGED
TO APPROACH THE GREAT LAKES AND UPPER OHIO VALLEY REGIONS ON
WEDNESDAY. INCREASING MOISTURE AND ASCENT IN SW FLOW AHEAD OF
THIS TROUGH WILL RESULT IN RAIN OVERSPREADING THE REGION TUESDAY
NIGHT THROUGH WEDNESDAY. AVERAGE ENSEMBLE BASED RAINFALL AMOUNTS
ARE CURRENTLY EXPECTED TO BE AROUND 1/4 OF AN INCH.
THE SURFACE FRONT IS EXPECTED TO BEGIN TO CROSS THE AREA LATE
WEDNESDAY AFTERNOON, AS THE UPPER TROUGH DEEPENS INTO AN UPPER
LOW ACROSS MICHIGAN AND WESTERN OHIO. CRITICAL THICKNESSES AND
MODEL SOUNDINGS INDICATE SOME POTENTIAL FOR A MIX OR CHANGEOVER
TO SNOW BY WEDNESDAY EVENING NORTH OF I-80.
KEY MESSAGE 3...
THE SURFACE FRONT IS EXPECTED TO SHIFT EAST OF THE AREA
WEDNESDAY NIGHT, AS A SURFACE WAVE DEVELOPS ALONG IT ACROSS THE
MID ATLANTIC REGION. AT THE SAME TIME, THE UPPER LOW IS PROGGED
TO DRIFT EAST ACROSS OHIO INTO PENNSYLVANIA WEDNESDAY NIGHT
THROUGH THURSDAY. RAIN IS EXPECTED TO CHANGE TO SNOW WEDNESDAY
EVENING, WITH ALL SNOW BY OVERNIGHT, IN COLD ADVECTION. THE
UPPER OHIO VALLEY REGION COULD ALSO BE IN CLOSE PROXIMITY TO THE
LEFT EXIT REGION OF A 250 MB JET, WHICH COULD ALSO ENHANCE
ASCENT WEDNESDAY NIGHT INTO THURSDAY.
WHILE UNCERTAINTY EXISTS IN THE DETAILS OF THE DEVELOPMENT OF
THIS SYSTEM, CURRENT NBM PROBABILITIES SHOW A LIKELY POTENTIAL
FOR SEVERAL INCHES OF SNOW ACROSS THE LAUREL HIGHLANDS AND
HIGHER TERRAIN OF NORTHERN WV. THERE IS ALSO A 50-60 PERCENT
PROBABILITY OF AT LEAST 1 INCH OF SNOW FOR THE LOWER ELEVATIONS.
INDIVIDUAL OPERATIONAL MODEL RUNS CONTINUE TO INDICATE VARYING
AMOUNTS OF SNOW ACROSS THE REGION THROUGH THIS PERIOD. STAYED
CLOSER TO ENSEMBLE BLENDS AND ENSEMBLE PROBABILITIES DURING THIS
PERIOD TO SMOOTH OUT SOME OF THESE DIFFERENCES. WILL MONITOR THE
DEVELOPMENT AND TRENDS WITH THIS SYSTEM OVER THE NEXT COUPLE OF
DAYS.
KEY MESSAGE 4...
MODEL ENSEMBLES INDICATE A LONGWAVE TROUGH WILL PERSIST ACROSS
THE EASTERN CONUS AT LEAST THROUGH THE WEEKEND/EARLY NEXT WEEK.
THIS WILL MAINTAIN COLDER THAN AVERAGE TEMPERATURES, WITH
PERIODIC SNOW CHANCES AS INDIVIDUAL SHORTWAVE ROTATE THROUGH THE
TROUGH.
AVIATION /06Z MONDAY THROUGH FRIDAY/
KEY MESSAGES...
1) WIDESPREAD MVFR RETURNS OVERNIGHT THROUGH EARLY MONDAY
2) VFR AND BREEZY SOUTHWEST WINDS RETURN MONDAY LATE MORNING AND
AFTERNOON
3) NEXT ROUND OF RESTRICTIONS AND PRECIPITATION IN THE FORECAST
OCCUR TUESDAY NIGHT INTO WEDNESDAY
------------------------------------------------------------
STRATOCU WITH MVFR CEILINGS PREVAILS TO START THE 06Z TAF CYCLE
AND CONTINUES THROUGH EARLY MONDAY MORNING. THE LOW CLOUD DECK
SCATTERS AND LIFTS LATE MORNING THROUGH AFTERNOON. VFR PREVAILS
THEREAFTER THROUGH THE REMAINDER OF THE TAF PERIOD.
SOUTHWEST WINDS WILL BE BREEZY MONDAY MORNING AND AFTERNOON,
WITH GUSTS TO AROUND 25 KNOTS POSSIBLE. GUSTS CEASE MONDAY
EVENING BUT WINDS DON'T GO CALM OVERNIGHT, INSTEAD REMAINING
AROUND 5-10 KNOTS OUT OF THE SOUTH-SOUTHWEST.
OUTLOOK...
VFR PREVAILS TUESDAY ALONG WITH AFTERNOON WINDS OUT OF THE
SOUTH-SOUTHWEST GUSTING TO 20-25 KNOTS. RESTRICTIONS AND PRECIP
CHANCES RETURN TUESDAY NIGHT AND WEDNESDAY AS THE NEXT LOW
PRESSURE SYSTEM IMPACTS THE REGION.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...WM
AVIATION...CERMAK
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