828
FXUS61 KPBZ 201135
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
735 AM EDT FRI MAR 20 2026
WHAT HAS CHANGED
QPF HAS TRENDED UP QUICKLY FOR THE FRIDAY RAINFALL WITH A MORE
CONVECTIVE ELEMENT RAISING TOTALS TO BETWEEN 0.25-0.75 INCHES
FOR MUCH OF THE REGION. HIGH TEMPERATURES ROSE SOME ON SUNDAY,
GIVEN A LATER FRONTAL PASSAGE AND MORE PRE-FRONTAL HEATING
THROUGHOUT THE DAYLIGHT HOURS SUNDAY.
KEY MESSAGES
1) THUNDERSTORM AND SEVERE WEATHER POTENTIAL FRIDAY AND SUNDAY.
2) WARMING TREND OVER THE COMING DAYS BEFORE A SUNDAY NIGHT
COLD FRONT.
DISCUSSION
KEY MESSAGE 1...
A TROUGH IN THE LARGELY WEST-NORTHWESTERLY UPPER-LEVEL FLOW PUSHES
A SURFACE LOW OVER THE NORTHWESTERN GREAT LAKES INTO THE
NORTHEAST. CURRENTLY, ENSEMBLES ARE INDICATING A WEAKER ROUND
OF SHOWERS/THUNDERSTORMS DURING THE EARLY AFTERNOON, AHEAD OF
THE FRONT. THERE IS AN INDICATION OF DAYTIME SURFACE HEATING
BEHIND IT SUPPLYING SOME MODERATELY WEAK INSTABILITY ON THE
ORDER OF 200-300 J/KG WHICH COULD LIMIT THUNDERSTORM DEVELOPMENT.
HOWEVER, IF THE CAPE IS COMBINED WITH VEERING WIND PROFILES AND
AMPLE DEEP LAYER SHEAR, THIS COULD ALLOW FOR SOME CELLULAR
STRUCTURES TO DEVELOP. EVEN THOUGH THERE IS LOW-LEVEL HODOGRAPH
CURVATURE, TORNADOES REMAIN A LOW PROBABILITY DUE TO UNCERTAINTY
WITH THUNDERSTORM DEVELOPMENT IN THE EVENING. SPC HAS RELEASED
A DAY 1 MARGINAL RISK (LEVEL 1 OUT OF 5) FOR SEVERE THUNDERSTORMS
TODAY.
WITH A MORE CONVECTIVE LOOK TO THE PRECIPITATION QPF
EXPECTATIONS ARE BETWEEN 0.10-0.50 INCHES. ENSEMBLES ARE
INDICATING HIGHER TOTALS ALONG THE RIDGES AND DECREASING
WESTWARD. HOWEVER, LOCALLY HIGHER TOTALS ARE POSSIBLE IN
HEAVIER SHOWERS AND THUNDERSTORMS. DESPITE THE UPTICK, LITTLE
IMPACT IS EXPECTED FROM THIS QPF.
A SECOND TROUGH AND ASSOCIATED SURFACE FRONT RETURN RAIN
CHANCES TO THE REGION SUNDAY-SUNDAY NIGHT. AMPLE HEATING IN
MOIST SOUTHERLY FLOW AHEAD OF THE FRONT SETS THE STAGE FOR
STORMS ONCE AGAIN AND THE MACHINE LEARNING MODELS ARE PROJECTING
SOME RISK OF SEVERE WEATHER. THE OVERNIGHT TIMING OF THE FRONT
AND A NOTABLE HIGH BIAS EARLY THIS SEASON IN THE MACHINE
LEARNING MODELS ACROSS OUR REGION BRING SOME QUESTION AS TO HOW
REAL A THREAT THIS WILL BE. SPC NOW HAS A MARGINAL RISK OUT FOR
MOST OF WESTERN PA AND NORTHERN WV WITH MOST OF EAST/CENTRAL
OHIO IN A SLIGHT RISK (LEVEL 2 OUT OF 5).
KEY MESSAGE 2...
SUBTLE HEIGHT RISES ACROSS THE REGION PAIRED WITH OVER 3 DAYS
OF GENERAL WAA AT 850 MB AND A LARGELY SOUTHERLY SURFACE FLOW
SUPPORT HIGH TEMPERATURES RISING EACH DAY THROUGH THE WEEKEND.
TODAY AND TOMORROW, TEMPERATURES ARE EXPECTED TO BE AROUND 5-10
DEGREES ABOVE NORMAL.
BY SUNDAY AFTERNOON, 850 MB TEMPERATURES ARE SET TO CLIMB AS
HIGH AS 15C. THIS COMBINED WITH A BREEZY SOUTHWESTERLY FLOW
AHEAD OF THE IMPENDING COLD FRONT WILL ALLOW HIGH TEMPERATURES
ACROSS MUCH OF THE AREA TO PUNCH INTO THE 70S, WITH UPPER 60S
NORTH OF I-80. PROBABILITIES FOR HIGH TEMPERATURES OVER 75
DEGREES F IS GREATER THAN 65% FOR PITTSBURGH AND AREAS TO ITS
SOUTHWEST. HIGH TEMPERATURES ON SUNDAY COULD BE AS MUCH AS
20-25 DEGREES ABOVE AVERAGE.
A COLD FRONT SWEEPS THE REGION SUNDAY NIGHT, WITH COOLER HIGH
PRESSURE FILTERING IN BEHIND IT. HIGH TEMPERATURES RETURN TO
NEAR NORMAL VALUES BUT CAN FALL ON THE ORDER OF 20-30 DEGREES
FROM SUNDAY TO MONDAY.
AVIATION /12Z FRIDAY THROUGH TUESDAY/
LIGHT AND VARIABLE WINDS ARE EXPECTED THROUGH 14Z ACROSS ALL
TERMINALS. SFC MIXING OF STRONGER WINDS ALOFT THAT WILL LEAD TO
GUSTY CONDITIONS LATE MORNING THROUGH EARLY EVENING AHEAD OF AN
APPROACHING COLD FRONT FROM THE SOUTHWEST/SOUTH.
THE PROBABILITY OF RAIN AND THUNDERSTORMS INCREASES BETWEEN 18Z
AND 20Z AS THE FRONT TRACKS ACROSS LAKE ERIE AND VENTURES SOUTH.
ANY INITIAL FORMATION IS MORE LIKELY AS A RAIN SHOWER. HIGHER,
BUT CONDITIONAL CHANCES OF SEVERE FALL MOSTLY IN THE 20Z TO 00Z
WIND OW AND SOUTH OF BVI. PERIODS OF LOW VIS AND MVFR CIGS ARE
EXPECTED WITH PASSING CONVECTION.
IN THE WAKE OF THE COLD FRONT, EXPECT CIGS TO DECREASE TO MVFR
AND POTENTIALLY IFR WITH RESIDUAL BOUNDARY LAYER MOISTURE.
PROBABILITIES OF IFR ARE HIGHEST AT FKL AND DUJ.
OUTLOOK...
VFR CIGS RETURN LATE MORNING SATURDAY. A FRONTAL PASSAGE SUNDAY
COULD RETURN STRONG THUNDERSTORMS TO THE REGION DURING THE
AFTERNOON.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...LUPO/AK
AVIATION...HEFFERAN/MILCAREK
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