232
FXUS61 KPBZ 140550
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
150 AM EDT MON SEP 14 2026
WHAT HAS CHANGED
CONFIDENCE IN LATER ARRIVAL TIME OF THE NEXT RAIN CHANCE BY
MIDWEEK IS A BIT HIGHER. NO OTHER SIGNIFICANT CHANGES.
KEY MESSAGES
1) DRY WEATHER IS EXPECTED INTO TUESDAY NIGHT. COOLER
TEMPERATURES TODAY AND TONIGHT, THEN A WARMUP TUESDAY.
2) WARM AND HUMID CONDITIONS RETURN WEDNESDAY AND THURSDAY,
ALONG WITH RAIN CHANCES.
DISCUSSION
KEY MESSAGE 1...
A FEW ISOLATED SHOWERS REMAIN ALONG THE WINDSHIFT/LEADING EDGE
OF DRIER AIR, WHICH IS CURRENTLY WORKING INTO THE RIDGES. THE
MAIN SHORTWAVE TROUGH AXIS ROTATES THROUGH THIS MORNING, WHICH
WILL BE FOLLOWED BY 500MB RIDGING THROUGH TUESDAY. ISOLATED
PATCHES OF FOG ARE POSSIBLE THIS MORNING DUE TO THE MOIST
GROUND, BUT DECREASING DEWPOINTS AND LINGERING LIGHT MIXING MAY
TEND TO LIMIT THIS SOMEWHAT.
CROSSING SURFACE HIGH PRESSURE WILL THEN PROVIDE DRY WEATHER
TODAY INTO AT LEAST TUESDAY EVENING. LINGERING LOWER HEIGHTS
ALOFT WILL SUPPORT HIGH TEMPERATURES SOME 5 TO 8 DEGREES BELOW
NORMAL TODAY. WITH THE SURFACE HIGH OVERHEAD TONIGHT, A CLEAR
AND SEASONABLY COOL NIGHT IS FORECAST, WITH LOWS IN THE 40S
EXPECTED IN THE RIDGES AND NORTH OF US-422. TEMPERATURES CLIMB
BACK ABOVE NORMAL TUESDAY IN 850MB WARM ADVECTION BEHIND THE
DEPARTING HIGH.
KEY MESSAGE 2...
THE NEXT CHANCE OF PRECIPITATION NOW APPEARS A BIT MORE LIKELY
TO HOLD OFF UNTIL LATE TUESDAY NIGHT OR WEDNESDAY MORNING, AS
THE NEXT SHORTWAVE TROUGH SKIRTS THE NORTHERN GREAT LAKES. ENSEMBLE
CLUSTERS SHOW SOME AGREEMENT IN KEEPING ELEVATED, QUASI-ZONAL
500MB HEIGHTS OVER THE OHIO VALLEY. THIS MAY HELP TO HANG AN
ASSOCIATED SURFACE FRONT CLOSER TO THE SHORES OF THE EASTERN
GREAT LAKES INTO THURSDAY BEFORE IT POTENTIALLY GETS A SOUTHWARD
PUSH. MACHINE-LEARNING GUIDANCE CONTINUES TO SUGGEST LOWER-END
SEVERE AND FLOODING THREATS.
THE HIGH HEIGHTS SHOULD ALSO KEEP TEMPERATURES ABOVE NORMAL,
AND WITH LOW-LEVEL SOUTHWEST FLOW PUSHING DEWPOINTS WELL INTO
THE 60S TO AROUND 70, AN INCREASE IN HEAT STRESS IS POSSIBLE.
PROBABILISTIC HEATRISK GUIDANCE SHOWS 50-90% CHANCES FOR
MODERATE (LEVEL 2 OF 4) OR HIGHER NEAR AND SOUTH OF PITTSBURGH
WEDNESDAY, AND CWA- WIDE ON THURSDAY. TEMPERATURES MAY THEN COOL
SLIGHTLY FRIDAY BEHIND THE FRONT.
AVIATION /04Z MONDAY THROUGH FRIDAY/
DRIER AIR IS ADVANCING TOWARDS THE RIDGES AS OF 06Z, ALONG WITH
A WIND SHIFT. AHEAD OF THIS BOUNDARY, A BRIEF PERIOD OF PATCHY
FOG AND MVFR/IFR CEILINGS IS POSSIBLE AT LBE AND MGW, BEFORE
IMPROVEMENT TO VFR WITH THE ARRIVAL OF DRIER AIR. ELSEWHERE,
OUTSIDE OF SOME PATCHY MVFR STRATOCUMULUS, VFR SHOULD PREVAIL AS
WELL. PATCHY FOG MAY BE HELD IN CHECK BY A LINGERING PRESSURE
GRADIENT AHEAD OF THE APPROACHING SURFACE HIGH, AS WELL AS
FALLING DEWPOINTS.
PAST SUNRISE, VFR SCATTERED CUMULUS IS FORECAST DURING THE
AFTERNOON, ALONG WITH NORTHERLY WIND AROUND 10 KNOTS. A CLEAR
AND CALM NIGHT IS EXPECTED AS A SURFACE HIGH CENTER CROSSES THE
REGION. JUST AFTER THE TAF PERIOD, A ROUND OF VALLEY FOG MAY SET
UP AS TEMPERATURES COOL INTO THE MID 40S TO THE LOWER 50S.
OUTLOOK...
OUTSIDE OF MORNING VALLEY FOG, VFR IS EXPECTED INTO TUESDAY
NIGHT UNDER HIGH PRESSURE. SHOWER AND THUNDERSTORM CHANCES
INCREASE FROM N-S LATE WEDNESDAY INTO LATE THURSDAY WITH THE
APPROACH AND PASSAGE OF A COLD FRONT. VFR SHOULD RETURN FRIDAY
AS THE FRONT EXITS AND HIGH PRESSURE BUILDS IN.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...CL
AVIATION...CL/LUPO
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page