914
FXUS61 KPBZ 101801
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
101 PM EST SAT JAN 10 2026
WHAT HAS CHANGED
CONFIDENCE IN SUNDAY MORNING SNOW BANDS AND SQUALLS CONTINUES TO
INCREASE AS A STRONG UPPER TROUGH CROSSES THE REGION. SNOWFALL
AMOUNTS IN THE RIDGES WILL BE HIGHER THAN THE LOWLANDS, AND
CONFIDENCE IN AT LEAST 3 INCHES HAS INCREASED ENOUGH TO WARRANT A
WINTER WEATHER ADVISORY FOR THE PENNSYLVANIA AND WEST VIRGINIA
RIDGES. WIND GUSTS ARE ALSO LIKELY TO EXCEED WIND ADVISORY
CRITERIA IN EASTERN TUCKER COUNTY.
KEY MESSAGES
1) RAIN CONTINUES TODAY AND THIS EVENING
2) SNOW RETURNS SUNDAY WITH POSSIBLE SQUALLS IN THE MORNING
3) GUSTY WIND SUNDAY WITH ADVISORY LEVEL GUSTS POSSIBLE IN EASTERN
TUCKER COUNTY
4) COLDER, MORE SEASONABLE TEMPERATURES WITH RAIN AND SNOW INTO
NEXT WEEK
DISCUSSION
KEY MESSAGE 1...
BROAD ASCENT BENEATH DIFFLUENT MID-LEVEL FLOW AND ALONG A PASSING
WARM FRONT HAS DRIVEN A SHIELD OF LIGHT TO MODERATE RAIN ACROSS THE
AREA INTO THIS AFTERNOON. EXPECT THIS WILL CONTINUE INTO TONIGHT AS
UPPER JET ASCENT OVERSPREADS AND A COLD FRONT SWEEPS THROUGH KEEPING
SYNOPTIC FORCING IN PLACE WITH SUFFICIENT MOISTURE. RAINFALL TOTALS
THROUGH TONIGHT WILL BE HIGHEST SOUTH OF PITTSBURGH WITH A 60-80%
CHANCE OF >0.5", HIGHEST ACROSS NORTHERN WV. NORTH OF PITTSBURGH,
TOTALS WILL SIT IN THE QUARTER TO HALF AN INCH RANGE WITH LESS THAN
A 40% CHANCE OF EXCEEDING 0.5". DRIER AIR WILL SETTLE IN IN THE MID-
LEVELS BEHIND THE COLD FRONT TONIGHT AND SHALLOW THE DEPTH OF THE
MOISTURE GIVING WAY TO A DRIER OVERNIGHT TIMEFRAME WITH SOME LIGHT
SHOWERS/DRIZZLE PERHAPS PERSISTING.
KEY MESSAGE 2...
AS COLDER AIR FILTERS IN SUNDAY MORNING, RAIN WILL TRANSITION TO
SNOW AFTER SUNRISE. THE CORE OF THE MID-LEVEL COLD AIR WILL SETTLE
IN AS A TROUGH/CLOSED LOW ROTATES THROUGH AND STEEPENS LOW LEVEL
LAPSE RATES. QUICK MOVING SNOW BANDS/SNOW SQUALLS ARE THUS LIKELY TO
DEVELOP ALONG A PRE-FRONTAL SURFACE TROUGH WITH PVA AIDING IN
ASCENT. THE MORE BROAD NATURE OF THE FORCING POINTS TOWARD A MORE
CELLULAR MODE TO THE BANDS, COHERENT ALONG THE PRE-FRONTAL TROUGH,
AS OPPOSED TO A DEFINED SQUALL LINE LIKE WE SAW ON NEW YEAR'S EVE.
MODEL CROSS SECTIONS SUGGEST ENHANCED OMEGA AND CONDITIONALLY
UNSTABLE LAPSE RATES WITHIN A SATURATED DGZ POINTING TOWARD THE
POTENTIAL FOR SLRS TO BE A BIT ABOVE THE NBM MEAN. WHERE EXACTLY
HEAVIER BANDS WILL BE IS DIFFICULT TO PINPOINT, BUT MOST CAMS
SUGGEST SOUTH OF US-422 TO NORTHERN WEST VIRGINIA WILL BE THE
LATITUDINAL EXTENT. HREF QPF SUGGESTS ONE POTENTIAL ENHANCED SWATH
ALONG AND SOUTH OF I-70 WITH ANOTHER, LESS DEFINED ONE, FARTHER
NORTH HOVERING AROUND PITTSBURGH METRO. SO, IT'S LIKELY IN THOSE TWO
AREAS THAT THERE'S THE MOST POTENTIAL FOR OVERPERFORMING AMOUNTS.
MOST WILL SEE A QUICK DUSTING TO HALF AN INCH OR SO, BUT VERY
LOCALIZED AMOUNTS ESPECIALLY WHERE BANDS PERSIST COULD REACH AS HIGH
AS 3". GIVEN LITTLE CONFIDENCE IN EXACTLY WHERE THIS MAY BE, AND THE
LIMITED SPATIAL EXTENT ANYWAY, HAVE REFRAINED FROM WINTER WEATHER
HEADLINES IN THE LOWLANDS. WHAT ALSO REMAINS A BIT UNCERTAIN IS ROAD
SURFACE TEMPERATURES, AND THUS HOW EFFICIENT ACCUMULATION MAY BE,
WITH HIGHS ON SATURDAY REACHING INTO THE UPPER 50S AND MOST OF THE
AREA BEING ABOVE FREEZING FOR THE PREVIOUS 48-60 HOURS. EVEN IF
SURFACES ARE A BIT WARM TO START, HEAVIER RATES WOULD LIKELY
OVERCOME THE WARM GROUND ANYWAY AND RESULT IN A QUICK BURST OF
ACCUMULATION AND REDUCTION TO VISIBILITY.
UPSLOPE FLOW WITH A WEST-NORTHWEST WIND WILL BE SUFFICIENT FOR
HIGHER SNOWFALL TOTALS AS PER USUAL IN THE RIDGES WITH MORE
PERSISTENT SNOW OUTSIDE OF THE MORNING BANDS AND AFTERNOON LAKE
EFFECT. NBM MEAN TOTALS IN EASTERN TUCKER AND PRESTON SIT AROUND 3-
4", WHICH IS A BIT SURPRISING GIVEN ITS TENDENCY TO UNDERDO THE
TERRAIN DRIVEN SNOW. HREF, ASSUMING A 10:1 SLR, HAS A SIMILAR 2-3"
WHICH IS LIKELY ON THE LOW SIDE WITH SLRS CLOSER TO 18:1. FOR THOSE
REASONS, HAVE ISSUED A WINTER WEATHER ADVISORY FOR EASTERN TUCKER,
EASTERN PRESTON, AND THE RIDGES OF WESTMORELAND AND FAYETTE WHERE
CONFIDENCE IN AT LEAST 3" IS HIGH; THE CHANCE OF HITTING WARNING
CRITERIA SNOW IS LOW, AND THE BEST SHOT WOULD BE THE WV RIDGES. THE
DEPTH OF THE MOISTURE WILL GRADUALLY SHRINK INTO THE EVENING AND
SNOW GROWTH WILL BECOME LESS EFFICIENT, BUT STILL THINK THAT ENOUGH
OROGRAPHIC EFFECTS AND REMNANT SHALLOW MOISTURE WILL BE ENOUGH TO
MAINTAIN FLURRIES AND LIGHT SNOW SHOWERS WITH MINOR ADDITIONAL
ACCUMULATION.
FINALLY, LAKE EFFECT SNOW WILL TURN ON AS A REINFORCING SURFACE
BOUNDARY CROSSES IN THE EARLY AFTERNOON HOURS. THIS LOOKS TO BE OF
THE STEADY LIGHT TO MODERATE VARIETY AND NOT POSE A THREAT FOR
ADDITIONAL HEAVY LAKE EFFECT BANDS WITH TOO MUCH DIRECTIONAL SHEAR,
BUT STILL, A BROAD 1-2" IS POSSIBLE ALONG AND NORTH OF I-80.
KEY MESSAGE 3...
THE OTHER THREAT OF SUNDAY WILL BE GUSTY WIND. THE GRADIENT WILL
TIGHTEN AS THE SURFACE TROUGHS MOVE THROUGH, AND EFFICIENT MIXING
WITH STEEPENED LAPSE RATES WILL ALLOW FOR TAPPING INTO A 40-45 KNOT
LOW LEVEL JET. THE PROBABILITY OF REACHING WIND ADVISORY CRITERIA IS
LOW FOR MOST OF THE AREA, AND PEAK GUSTS ARE LIKELY TO BE IN
THE 35- 40 MPH RANGE. FOR EASTERN TUCKER COUNTY, HOWEVER, THE
PROBABILITY IS QUITE HIGH AT 90+%. CAN'T ENTIRELY RULE OUT THE
HIGHEST ELEVATIONS IN THE COUNTY REACHING HIGH WIND WARNING
CRITERIA, BUT THAT THREAT LOOKS TO BE VERY LOCALIZED, SO HAVE
GONE AHEAD WITH A WIND ADVISORY TO COVER THE WIND THREAT.
KEY MESSAGE 4...
NORTHWEST FLOW REESTABLISHES NEXT WEEK WITH GENERAL TROUGHINESS
PLAGUING THE EAST COAST AND ROUNDS OF SHORTWAVES DIVING THROUGH THE
GREAT LAKES BY MID-WEEK. THIS WILL PROVIDE MORE SEASONABLE
TEMPERATURES THAN WHAT WE'VE BEEN SEEING SO FAR SINCE THE CALENDAR
FLIPPED TO 2026. A DEEPER WAVE LOOKS TO DIVE THROUGH SOMETIME LATE
TUESDAY AND WEDNESDAY AS A SURFACE LOW DEVELOPS WELL OFF TO OUR
NORTH AND RETURNS PRECIPITATION CHANCES. THIS MAY COME IN THE FORM
OF RAIN AND SNOW... RAIN INITIALLY WITH SUFFICIENT WARMER AIR IN
PLACE BEFORE TRANSITIONING TO SNOW WITH MUCH COLDER, BELOW-NORMAL,
TEMPERATURES SIGNALED IN LONGER RANGE ENSEMBLES.
AVIATION /18Z SATURDAY THROUGH THURSDAY/
KEY MESSAGES...
1) WIDESPREAD RESTRICTIONS AND SHOWERS RETURN THIS AFTERNOON AND
INTO THE EVENING WITH CROSSING LOW PRESSURE AND ASSOCIATED FRONT
3) WESTERLY WIND SHIFT OVERNIGHT AND TRANSITION TO SCATTERED
SNOW SUNDAY.
------------------------------------------------------------
LOW PRESSURE LIFTING UP THE EASTERN SEABOARD TODAY RETURNS
WIDESPREAD RAIN SHOWERS AND CIG RESTRICTIONS TO THE REGION LATER
THIS MORNING AND INTO THE AFTERNOON FROM SOUTH TO NORTH. LATEST
ENSEMBLE GUIDANCE SHOWS A 70-80% PROBABILITY OF IFR CIGS. MODEL
SOUNDINGS SHOW CIGS SHOULD LIFT SHORTLY AFTER FRONTAL PASSAGE,
BUT INTERMITTENT IFR VIS RESTRICTIONS WILL BE POSSIBLE WITH POST
FRONTAL SNOW ON SUNDAY WITH STRONG COLD ADVECTION. GUSTS
BETWEEN 20-30KTS WILL PERSIST THROUGH THE TAF PERIOD AFTER
FRONTAL PASSAGE.
OUTLOOK...
VFR RETURNS MONDAY AND WILL LIKELY CONTINUE UNTIL LATER TUESDAY
INTO WEDNESDAY WHEN RESTRICTIONS RETURN AS THE NEXT LOW PRESSURE
SYSTEM IMPACTS THE REGION.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...WINTER WEATHER ADVISORY FROM 8 AM SUNDAY TO 1 AM EST MONDAY
FOR PAZ074-076.
OH...NONE.
WV...WINTER WEATHER ADVISORY FROM 8 AM SUNDAY TO 1 AM EST MONDAY
FOR WVZ512-514.
WIND ADVISORY FROM 8 AM SUNDAY TO 1 AM EST MONDAY FOR WVZ514.
DISCUSSION...MLB
AVIATION...88
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