338
FXUS61 KPBZ 050136
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
836 PM EST THU DEC 4 2025
SYNOPSIS
HIGH PRESSURE WILL PROMOTE CLEARING SKIES AND LIGHT WIND WHICH,
COMBINED WITH EXISTING SNOW COVER, WILL RESULT IN OVERNIGHT
LOWS DIPPING INTO THE SINGLE DIGITS TO MID-TEENS. ADDITIONAL
LIGHT SNOW CHANCES AND BELOW- NORMAL TEMPERATURES SHOULD
CONTINUE INTO EARLY NEXT WEEK.
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/
KEY MESSAGES:
- NEAR-RECORD LOW TEMPERATURES FRIDAY MORNING
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AS FLOW ALOFT LIGHTENS AND BECOMES MORE ZONAL, SURFACE HIGH
PRESSURE WILL SLIDE OVER THE UPPER OHIO RIVER VALLEY OVERNIGHT.
SUBTLE SHORTWAVE MOVEMENT SOUTHEAST WITH A DEVELOPING LOW WILL
OFFER LITTLE MORE THAN CLOUD COVER POTENTIAL THROUGH FRIDAY
MORNING.
THE COMBINATION OF THE COLD AIR MASS, CLEARING SKIES, RESIDUAL
SNOWPACK AND LIGHT WIND CREATES HIGH CONFIDENCE IN IT BEING THE
COLDEST NIGHT OF THE SEASON AS TEMPERATURE FALLS INTO THE
SINGLE DIGITS (NORTH OF PITTSBURGH) TO TEENS. THIS PUTS DAILY
LOW RECORDS AT RISK OF BEING BROKEN FOR MOST OF THE REGION'S
CLIMATE SITES (SEE CLIMATE SECTION FOR SPECIFIC VALUES AT PLAY).
HOWEVER, THERE REMAINS A DECENT SPREAD IN POTENTIAL LOW
TEMPERATURES THAT CREATES UNCERTAINTY IN THOSE RECORDS FALLING,
IN SMALL PART DUE TO SOME LOCATIONS SEE ENOUGH WIND MIXING TO
LIMIT COOLING. MORE LIKELY, FOR AREAS NEAR/SOUTH OF I-70, THE
VARIABILITY IN THE OUTCOMES IS BEING DRIVEN BY THE POTENTIAL FOR
INCREASING MID TO HIGH LEVEL CLOUDS SOUTH OF PITTSBURGH FROM
THE SOUTHERN SHORTWAVE. AND FOR AREAS TO THE NORTH, THAT
VARIABILITY IS SIMILAR (I.E. EXTENT OF CLOUD COVERAGE) BUT
TETHERED TO SOME UNCERTAINTY IN THE EROSION OF LAKE ERIE
INFLUENCED STRATOCU.
SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/
KEY MESSAGES:
- NEAR-RECORD LOW TEMPERATURES FRIDAY MORNING.
- LOW CONFIDENCE IN SNOW FRIDAY.
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GENERALIZED ZONAL FLOW OVER THE OHIO VALLEY ON FRIDAY WILL BE
MARRED SLIGHTLY BY A FLAT MID-LEVEL WAVE, WITH A SURFACE
REFLECTION TRACKING ACROSS THE DEEP SOUTH. THE MOST LIKELY
SCENARIO REMAINS A ROUND OF LIGHT SNOW FOR THE WV RIDGES OF
UNDER AN INCH. THE TOTAL RANGE OF SCENARIOS RUN FROM A FAR
SOUTH STORM TRACK WITH NO SNOW AT ALL IN THE FORECAST AREA, TO
A PARTIAL RE-CURVE ALONG THE ATLANTIC COAST THAT COULD PUSH
LIGHT SNOW AS FAR NORTH AS PITTSBURGH, AND PROVIDE A FEW INCHES
TO THE RIDGES OF PRESTON/TUCKER COUNTIES. GIVEN THE PATTERN, THE
FORMER SEEMS LIKE A MORE REASONABLE OUTCOME THAN THE LATTER.
ANY SNOW WOULD DEPART BY SUNSET, LEAVING A DRY AND COLD FRIDAY
NIGHT.
LONG TERM /SATURDAY THROUGH THURSDAY/
KEY MESSAGES:
- BELOW NORMAL TEMPERATURES CONTINUE INTO EARLY NEXT WEEK.
- MORE WINTER WEATHER POTENTIAL.
-------------------------------------------------------------------
THE TROUGHING PATTERN CONTINUES THROUGH THE EXTENDED PERIOD,
CONTINUING THE TREND OF BELOW-NORMAL TEMPERATURES. PERIODIC
SHORTWAVES WITHIN THE LONGWAVE PATTERN WILL PROVIDE SEVERAL
CHANCES FOR SNOW THROUGH THE PERIOD. AT THIS TIME THERE IS NOT A
SIGNAL FOR ANY LARGE EVENT, BUT IN ANY CASE, THERE IS GENERALLY
A 20 TO 50 PERCENT CHANCE ACCORDING TO THE NBM OF A TOTAL SNOW
ACCUMULATION OF ONE INCH OR MORE THROUGH THE PERIOD. THE HIGHEST
CHANCES OF ANY ACCUMULATIONS WOULD BE FOR THE PA/WV RIDGES, AND
THE LOWEST WOULD BE IN EASTERN OHIO. A REINFORCEMENT OF COLD
TEMPERATURES APPEARS LIKELY; MAXIMUM VALUES IN THE 30S
SATURDAY/SUNDAY HAVE A 70 PERCENT CHANCE OR GREATER OF FALLING
BELOW FREEZING ON MONDAY.
MID-TO-LATE WEEK TEMPERATURE UNCERTAINTIES WOULD BE MORE TIED
TO AMPLITUDE UNCERTAINTY OF THE SEMI-PERSISTANT EASTERN TROUGH.
A STRONGER PREVAILING TROUGH WOULD ALLOW FOR COOLER CONDITIONS,
WITH HIGHER CHANCES OF LOW-QPF SNOWFALL. A WEAKER TROUGH WOULD
LIKELY CORRELATE TO WARMER CONDITIONS WITH HIGHER QPF POTENTIAL
IN MIXED PRECIPITATION EVENTS.
AVIATION /01Z FRIDAY THROUGH TUESDAY/
KEY MESSAGES:
- SNOW IS ENDING
- CLEARING IS EXPECTED TONIGHT WITH MUCH COLDER TEMPERATURES
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LOCATIONS SHOULD REMAIN VFR THROUGH THE NIGHT WITH THE EXCEPTION OF
FKL AND DUJ. A TEMPO WAS USED TO SHOW FLUCTUATION BETWEEN MVFR
AND VFR THROUGH LATE THIS EVENING AS THE HREF PROBABILITIES
STILL GIVE A 50%-60% PROBABILITY OF CEILINGS AT/UNDER 3000 FT.
WINDS WILL BECOME CALM OVERNIGHT.
TOMORROW, WINDS WILL BE LIGHT AS THEY SHIFT TO OUT OF THE
SOUTHWEST. MVFR CEILING RESTRICTIONS LIKELY WITH A LOW PRESSURE
SYSTEM PASSING TO THE SOUTH. THERE IS SOME UNCERTAINTY IF PIT,
HLG, AND FKL WILL SEE SOME CEILINGS LOWER THAN 2000 FT FOR MORE
THAN A COUPLE OF HOURS.
OUTLOOK...
RESTRICTIONS ARE LIKELY TO PERSIST INTO SATURDAY AND
SUNDAY WITH A CROSSING COLD FRONT. ON SUNDAY, ANOTHER SNOW SHOWER
EVENT WILL MAKE MVFR AND IFR RESTRICTIONS POSSIBLE.
CLIMATE
AT LEAST FOUR OF OUR CLIMATE SITES HAVE A CHANCE TO CHALLENGE
RECORD LOW TEMPERATURES FOR DECEMBER 5 ON FRIDAY MORNING. TWO
OTHER SITES ARE LESS LIKELY TO APPROACH THEIR RECORD LOWS.
CURRENT 12/5 FORECAST
SITE RECORD LOW LOW
---- ---------- ------------
PITT INTL 12 (1976) 11
MORGANTOWN 11 (1974) 16
DUBOIS 10 (1991) 7
WHEELING 12 (1944) 13
ZANESVILLE 3 (1957) 11
NEW PHILADELPHIA 2 (1966) 8
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
SYNOPSIS...CL/88
NEAR TERM...FRAZIER
SHORT TERM...CL/88
LONG TERM...CL/88
AVIATION...LUPO
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