285
FXUS61 KCTP 290806
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
406 AM EDT WED APR 29 2026
WHAT HAS CHANGED
* ADDED +FG AOA 2000FT ACROSS THE WESTERN/NORTHERN ALLEGHENIES
* ADDED AREAS OF FROST THURSDAY-SATURDAY NIGHT
KEY MESSAGES
1) WET WEDNESDAY WITH WIDESPREAD DRENCHING RAINFALL AND A FEW
STRONG THUNDERSTORMS POSSIBLE IN SOUTHWEST PA
2) CHILLY PATTERN FOR THE END OF APRIL WITH FROST/FREEZE RISK
THROUGH THE FIRST WEEKEND OF MAY
DISCUSSION
KEY MESSAGE 1: WET WEDNESDAY WITH WIDESPREAD DRENCHING RAINFALL
AND A FEW STRONG THUNDERSTORMS POSSIBLE IN SOUTHWEST PA
EXTENSIVE LOW CLOUDS AND RIDGE-SHROUDING/LOCALLY DENSE FOG
ACROSS CPA THIS MORNING. WE ADDED +FG AT ELEVATIONS AOA 2000FT
BASED ON BLEND OF ASOS/RWIS DATA WITH VISIBILITY 0.5-1KFT.
DRENCHING RAINFALL IS EXPECTED TO EXPAND FROM SOUTHWEST TO
NORTHEAST THROUGH THE AFTERNOON AND EVENING BEFORE TAPERING OFF
AND SHIFTING TO THE EAST LATE TONIGHT INTO EARLY THURSDAY
MORNING. RAIN MAY BE HEAVY AT TIMES PARTICULARLY ACROSS THE NW
ALLEGHENIES WITH >1" AMOUNTS POSSIBLE BASED ON HREF/REFS PMM
QPF SIGNAL. WHILE LARGELY BENEFICIAL ESPECIALLY IN D1-D2 DROUGHT
AREAS IN THE FAR SOUTHEAST PART OF THE CWA, SOME ROADWAY
PONDING OR MINOR LOW LYING/POOR DRAINAGE RUNOFF ISSUES ARE
POSSIBLE.
SPC HAS MAINTAINED A LEVEL 1/5 MRGL RISK SWO OVER SOUTHWEST PA,
BUT THE LACK OF INSTABILITY CONTINUES TO CAST CONSIDERABLE
UNCERTAINTY IN THE DEVELOPMENT OF STRONG STORMS. SECONDARY LOW
FORMATION ALONG/SOUTH OF THE MD LINE SUGGESTS GREATEST SEVERE
STORM RISK IS PROBABLY FARTHER TO THE SOUTH INTO THE WARM
SECTOR OVER WV/VA.
--------------------------------------------------------------
KEY MESSAGE 2: CHILLY PATTERN FOR THE END OF APRIL WITH
FROST/FREEZE RISK THROUGH THE FIRST WEEKEND OF MAY
SEVERAL DISTURBANCES ROTATING AROUND A PERSISTENT UPPER LEVEL
CLOSED LOW CENTERED OVER ONTARIO AND QUEBEC WILL HELP TO
REINFORCE BROADLY DEEP TROUGHING ACROSS THE EASTERN U.S. INTO
NEXT WEEK. THIS PATTERN WILL KEEP CONDITIONS COOL AND UNSETTLED
WITH TEMPERATURES BELOW SEASONAL NORMS. CHILLY NIGHTTIME LOWS
WILL ALSO LEAD TO FROST AND FREEZE CONCERNS THURSDAY-SATURDAY
NIGHT. THE GROWING SEASON IS NOW ACTIVE ACROSS ALL CPA ZONES.
AVIATION /07Z WEDNESDAY THROUGH SUNDAY/
A MIXTURE OF MVFR TO IFR CEILINGS ARE ALREADY BEING OBSERVED
OVER WESTERN PENNSYLVANIA. CEILINGS WILL GRADUALLY DETERIORATE
AREAWIDE LATER TONIGHT INTO WEDNESDAY, WITH IFR/LIFR LIKELY
EVERYWHERE ACROSS WEST AND CENTRAL PA (BFD, JST, AOO, UNV) AND
MVFR FAVORED AT IPT, MDT, AND LNS. THERE IS SOME UNCERTAINTY IN
THE ONSET OF CEILING RESTRICTIONS ACROSS THE REGION, AND LOWER
CEILINGS MAY WORK INTO THE SOUTHEAST EARLIER THAN CURRENTLY
CONVEYED IN THE TAF PACKAGE. THERE IS ALSO SOME POTENTIAL FOR
REDUCED VISIBILITY IN LOW CLOUDS/FOG, ESPECIALLY ACROSS THE
WEST. WHETHER THIS WILL MANIFEST IN SIMPLY LOW CEILINGS OR IN
REDUCED VISIBILITY REMAINS A BIT UNCLEAR. BUT IFR/LIFR
RESTRICTIONS ARE EXPECTED REGARDLESS.
MORE WIDESPREAD SHOWERS, AND PERHAPS SOME THUNDERSTORMS, WILL
OVERSPREAD THE AREA ON WEDNESDAY FROM SOUTHWEST TO NORTHEAST.
VISIBILITY RESTRICTIONS ARE LIKELY (MVFR/IFR) AS CEILINGS REMAIN
LOW. THE BEST CHANCE FOR THUNDER WILL BE IN SOUTHERN PA, FIRST
AFFECTING JST AND THEN POTENTIALLY EXTENDING EAST TOWARD MDT AND
LNS LATER IN THE AFTERNOON/EVENING. MENTIONS OF TSRA HAS NOT
BEEN MADE IN THIS TAF PACKAGE AS THERE IS STILL TOO MUCH
UNCERTAINTY REGARDING THE TIMING OF THE MORE ACTIVE SHOWERS.
CONFIDENCE IS HIGH IN LITTLE TO NO VFR CONDITIONS FOR WEDNESDAY.
A MENTION OF NO SCHEDULED AMENDMENTS HAS BEEN ADDED FOR KAOO AND
KJST AS THERE IS A DATA FLOW PROBLEM FROM THE METAR TO US, BUT
WE CAN CALL INTO THE SITE FOR THE CURRENT METAR.
OUTLOOK...
WED...MVFR/IFR FAVORED DUE TO LOW CLOUD CEILINGS & RAIN
OVERSPREADING THE REGION. -TSRA POSSIBLE SOUTH.
THU...VFR/MVFR IN THE MORNING AS RAIN ENDS WEST TO EAST,
BECOMING VFR IN THE AFTERNOON.
FRI-SAT...MAINLY VFR WITH BRIEF RESTRICTIONS POSSIBLE IN
SHOWERS.
SUN...RESTRICTIONS POSSIBLE NORTHWEST IN -RA AND POSSIBLY SOME
-SN.
CTP WATCHES/WARNINGS/ADVISORIES
NONE.
WHAT HAS CHANGED...STEINBUGL
KEY MESSAGES...STEINBUGL
DISCUSSION...STEINBUGL
AVIATION...BANGHOFF/BOWEN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page