588
FXUS61 KPBZ 130016 AAB
AFDPBZ
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PITTSBURGH PA
816 PM EDT MON OCT 12 2026
WHAT HAS CHANGED
LITTLE CHANGE IN MESSAGING WITH LATEST ROUND OF MODEL GUIDANCE.
KEY MESSAGES
1) UNSEASONABLY WARM ON TUESDAY WITH NEAR-RECORD-HIGH
TEMPERATURE. RAIN CHANCES ON WEDNESDAY WITH STALLED FRONT.
2) BELOW-AVERAGE TEMPERATURES, RAIN WITH LOW-PROBABILITY SNOW
SHOWERS, AND GUSTY CONDITIONS EXPECTED WITH LARGE-SCALE
DISTURBANCE FRIDAY INTO SATURDAY.
DISCUSSION
KEY MESSAGE 1...
HEIGHT RISES ALOFT AND INCREASING WARM SWLY SURFACE FLOW
STARTING THIS EVENING (AS A WEAK SHORTWAVE TROUGH CROSSES NORTH
OF MICHIGAN) FAVORS DRY WEATHER AND RISING TEMPERATURE BY TUE
AFTERNOON. SHORTER PERIOD-OF-RECORD SITES LIKE NEW PHILADELPHIA
MAY SEE HIGHS THAT TIE/BREAK THE DAILY RECORD (20-30%
PROBABILITY) WHILE MOST OTHERS JUST EXPERIENCE HIGHS THAT ARE
10-15 DEG ABOVE THE DAILY AVERAGES.
SUBTLE EMBEDDED SHORTWAVE TROUGHS ALONG THE NORTHERN RIDGE
PERIPHERY WILL PUSH A COLD FRONT SWD INTO THE REGION ON WED
BEFORE THE BOUNDARY STALLS. SOME UNCERTAINTY REMAINS IN HOW FAR
SOUTH THE BOUNDARY REACHES BEFORE STALLING, BUT AT THIS TIME
APPEARS MOST LIKELY NEAR THE I-70 CORRIDOR. THIS WILL FAVOR A
TREND TOWARD SEASONABLE TEMPERATURE INTO THU WITH RAIN SHOWERS
MAINLY WED AFTERNOON/EVENING.
KEY MESSAGE 2...
ENSEMBLE FORECASTS ARE FAVORING THE DEVELOPMENT OF A NOTABLE
UPPER-LEVEL TROUGH THAT WILL DIVE SEWD THROUGH THE GREAT LAKES
REGION STARTING EARLY FRI MORNING AND INTO SAT, WITH CLUSTER
ANALYSIS FAVORING A MODESTLY STEEP BUT PROGRESSIVE
TROUGH/SURFACE LOW SYSTEM. THE MODEL MEAN PATTERN WOULD LEND TO
RAIN WITH POTENTIALLY ADVISORY-LEVEL WIND GUSTS (AND/OR GUSTY
WIND-DRIVEN SHOWERS) FRI, WANING PRECIPITATION WITH BREEZY BUT
LOW-IMPACT WIND GUSTS SAT, AND A LOW PROBABILITY (~10-15%
CHANCE) FOR LAKE-ENHANCED RAIN/SNOW SHOWERS SAT MORNING IN
NORTHWEST PA.
CURRENT GUIDANCE FAVORS WEST-CENTRAL PA TO HIGHER TERRAIN
LOCATIONS FOR WIND GUSTS THAT REACH WIND ADVISORY CRITERION
(GUSTS OF AT LEAST 46 MPH) WITH NON-ZERO PROBABILITY OF GUSTS
REACHING HIGH WIND WARNING THRESHOLD ALONG RIDGE LINES OF ERN
TUCKER COUNTY. HOWEVER, VARIANCE IN FRONTAL TIMING AND DEPTH OF
POST-FRONTAL MIXING ARE THE PRIMARY INDICATORS TO MONITOR IN
WHETHER WIND RISK BECOME MORE/LESS LIKELY IN THE DAYS AHEAD.
PREVIOUS DISCUSSION OF THE FIRST SNOWFLAKES OF THE YEAR (AND
EVEN ACCUMULATION) HAVE TAKEN A HIT IN THE PROBABILISTIC SPACE
DUE TO SOME COALESCENCE OF MODELED SYNOPTIC PATTERN OF A MORE-
PROGRESSIVE SYSTEM THAT BOTH LIMITS THE DEGREE OF COLD ADVECTION
AND DURATION OF IDEAL LAKE-EFFECT WIND DIRECTION. SNOW BIRDS
WILL WANT TO SEE ENSEMBLE TRENDS TOWARD A DEEPER, SLOWER TROUGH
(MAINLY SUGGESTED BY A HANDFUL OF CANADIAN ENSEMBLE MODEL
MEMBERS) IN ORDER TO RETURN HIGHER PROBABILITIES OF SEEING THE
FIRST FLAKES OF THE YEAR.
AVIATION /00Z TUESDAY THROUGH SATURDAY/
GENERALLY, CLEAR SKIES ARE FORECAST OVERNIGHT WITH A FEW PASSING
CLOUDS. LIGHT WINDS SHOULD PRECLUDE MANY FOG MENTIONS BUT
CHANCES INCREASE FOR FKL AND DUJ TO A 30% CHANCE AND 65% CHANCE
OF FOG RESPECTIVELY. GIVEN A SOUTHWEST WIND DIRECTION, OPTED TO
NOT MENTION AT FKL, BUT INCLUDE FOR DUJ (WITH POTENTIAL FOR
DENSE FOG) THROUGH DAYBREAK. ADDITIONALLY, THERE IS A LOW CHANCE
OF SOME MORNING SHOWERS PASSING THROUGH DUJ/FKL, BUT CHANCES
ONLY MAXIMIZE AT 30% FOR FKL AROUND 12Z.
INTO THE DAY TOMORROW, WIDS WILL GENERALLY GUST OUT OF THE
SOUTHWEST 20KTS TO 30KTS WITH PREVIALING VFR CONDITIONS.
OUTLOOK...
RAIN CHANCES RETURN WITH LOWER-PROBABILITY SHOWER POTENTIAL
WEDNESDAY MORNING, WITH A HIGHER PROBABILITY CHANCE OF
SHOWERS/STROMS INTO THE AFTERNOON. RESTRICTIONS SPREAD FROM
NORTH TO SOUTH DURING THE DAY. WIDESPREAD GUSTY WINDS HAVE
BECOME MORE CONFIDENT ON FRIDAY.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...KRAMAR/FRAZIER
AVIATION...MILCAREK
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