283
FXUS61 KPBZ 222338
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
738 PM EDT TUE APR 22 2025
SYNOPSIS
PRECIPITATION CHANCES REMAIN LOW THROUGH LATE THURSDAY UNDER
HIGH PRESSURE. SHOWER AND THUNDERSTORM CHANCES INCREASE FRIDAY
INTO SATURDAY. ABOVE AVERAGE TEMPERATURES EXPECTED INTO THE
WEEKEND.
NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/
KEY MESSAGES:
- DRY AND QUIET WEATHER INTO EARLY WEDNESDAY
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7:30PM UPDATE: NO MAJOR CHANGES MADE DURING THIS FORECAST
PERIOD.
PREVIOUS UPDATE:
CLEAR SKY AND LIGHT WINDS OVERNIGHT SHOULD GIVE US OUR COOLEST
NIGHT IN SEVERAL DAYS. HOWEVER, LOW TEMPERATURES ARE STILL
LIKELY TO BE NEAR/SLIGHTLY ABOVE AVERAGE FOR THIS TIME OF YEAR
WITH AN ENHANCED RIDGE AXIS OVER THE EAST COAST.
SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/
KEY MESSAGES:
- DRY WEATHER THROUGH THURSDAY
- WARMING TEMPERATURES BOTH WEDNESDAY AND THURSDAY
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SUBTLE 500MB HEIGHT RISES ARE EXPECTED WEDNESDAY AS A DISJOINTED
UPPER RIDGE SLIDES ACROSS SOUTHERN ONTARIO. THIS WILL RETURN A
WARMING TREND TO THE REGION, HELPING TO KICK OUR HIGH
TEMPERATURES BACK UP TO AROUND 10 DEGREES ABOVE AVERAGE.
FURTHER 500MB HEIGHT RISES ARE EXPECTED DURING THE DAYTIME ON
THURSDAY AS THE SOUTHERN PORTION OF THIS DISJOINTED UPPER RIDGE
STRENGTHENS OVER US. HIGH TEMPERATURES ARE EXPECTED TO SURGE
PAST 80 DEGREES FOR MUCH OF THE AREA (LARGELY OVER 60% CHANCE
SOUTH OF I-80 AND LARGELY OVER 90% CHANCE SOUTH OF I-70). NBM
PROBABILITIES FOR 85 DEGREES OR MORE ARE ALSO NOTABLE, WITH SOME
HOT SPOTS BETWEEN 40- 60+% MAINLY TIED TO THE RIVER VALLEYS
SOUTH OF I-70. SOME OF THESE PROBABILITIES SNEAK INTO THE
GREATER PITTSBURGH AREA AS WELL. HELPING THIS, NBM MEAN CLOUD
COVER IS PRETTY SCANT AND EVEN A REASONABLE CLOUDIEST SCENARIO
(90TH PERCENTILE) STILL HAS LARGE SWATHS OF THE REGION LARGELY
CLOUD FREE.
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/
KEY MESSAGES:
- INCREASING SHOWER CHANCES LATE WEEK INTO SATURDAY
- TROUGH SPEED WILL DETERMINE TIMING OF RETURN TO ABOVE AVERAGE
TEMPS
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AN UPPER TROUGH IS EXPECTED TO BE MOVING EASTWARD THROUGH THE
CENTRAL CONUS ON THURSDAY. INCREASING MOISTURE AND WARM
ADVECTION AHEAD OF THIS TROUGH RETURNS SHOWER CHANCES TO THE
AREA THURSDAY NIGHT. THE ASSOCIATED SURFACE FRONT IS EXPECTED TO
TRACK ACROSS THE UPPER OHIO VALLEY REGION FRIDAY AND FRIDAY
NIGHT WITH SHOWERS AND THUNDERSTORMS POSSIBLE. CLUSTERED
ENSEMBLES BRING THE UPPER TROUGH THROUGH THE REGION SATURDAY BUT
DIFFER ON THE EXACT TIMING DUE TO A SIGNAL FOR A POSSIBLY
WEAKER TROUGH. SHOWERS ARE EXPECTED TO SHUT OFF FROM WEST TO
EAST AS THE TROUGH EXITS THE REGION.
500MB HEIGHTS ARE EXPECTED TO BE ON THE RISE AGAIN SUNDAY
RETURNING DRY WEATHER AND WARMING TEMPERATURES. THE DEGREE TO
WHICH WE WARM REMAINS IN QUESTION AS CLUSTERED ENSEMBLES FAVOR
STUBBORNNESS FROM OUR PRIOR TROUGH IN EXITING THE EASTERN
SEABOARD AS A STRONG RIDGE BUILDS ACROSS THE CENTRAL CONUS. A
MORE STUBBORN, SLOWER TROUGH FAVORS A COOLER END TO THE WEEKEND.
THE CENTRAL CONUS RIDGE TRANSLATES EASTWARD TO BEGIN NEXT WEEK
AND WILL LIKELY BRING DRY WEATHER, LARGELY CLEAR SKIES AND
ABOVE AVERAGE TEMPERATURES.
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
HIGH PRESSURE WILL DOMINATE WITH HIGH CONFIDENCE VFR CONDITIONS
THROUGH WEDNESDAY. SOME PASSING CIRRUS WILL CONTINUE OVERNIGHT
TONIGHT WITH MOISTURE STREAMING OVERHEAD. WIND WILL TURN LIGHT
AND VARIABLE OVERNIGHT.
SKIES WILL BE MOSTLY CLEAR ON WEDNESDAY AND, WITH WEAK FLOW
ALOFT AND A LIGHT PRESSURE GRADIENT UNDER THE HIGH, WIND WILL
AGAIN BE 5 KNOTS OR LESS EVEN WITH MIXING AND GRADUALLY VEER
FROM SOUTHEASTERLY AROUND TO WESTERLY THROUGH THE DAY.
OUTLOOK...
WEAK SHORTWAVE MOVEMENT NORTH OF THE REGION MAY AID DECAYING
CONVECTION TO REACH FKL/DUJ LATE WEDNESDAY EVENING.
SHOWER AND THUNDERSTORM CHANCES WITH RISING RESTRICTION
PROBABILITIES WILL ACCOMPANY THE PASSAGE OF A LOW PRESSURE
SYSTEM STARTING LATE THURSDAY NIGHT INTO SATURDAY MORNING. THERE
IS HIGH CONFIDENCE IN VFR AND DRY WEATHER DEVELOPING BY SUNDAY
UNDER DRIER NORTHWEST FLOW AND BUILDING HIGH PRESSURE.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
SYNOPSIS...HEFFERAN
NEAR TERM...HEFFERAN
SHORT TERM...AK
LONG TERM...AK
AVIATION...FRAZIER/MLB
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