604
FXUS61 KCTP 060035
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
835 PM EDT MON MAY 5 2025
SYNOPSIS
* SLOW MOVING BANDS OF SHOWERS AND THUNDERSTORMS THIS EVENING COULD
PRODUCE LOCALIZED FLASH FLOODING, STRONG WINDS, AND HAIL.
* MORE SHOWERS/STORMS TUESDAY AND WEDNESDAY BEFORE AN UPPER LOW
FINALLY LOSES ITS GRIP ON PENNSYLVANIA.
* TRENDING COOLER THURSDAY AND FRIDAY WITH POTENTIAL FOR ANOTHER
BATCH OF HEAVY RAIN
NEAR TERM /UNTIL 6 AM TUESDAY MORNING/
UPPER LEVEL DIVERGENCE ASSOCIATED WITH AN APPROACHING VORT MAX
ON THE EAST SIDE OF A LARGE, SLOW MOVING UPPER LOW WILL MAINTAIN
CLUSTERS AND LINES OF HEAVY SHOWERS WITH EMBEDDED CONVECTION
THROUGH MUCH OF TONIGHT. A SEVERE THUNDERSTORM WATCH FOCUSED ON
CONVECTION IN MARYLAND AND VIRGINIA ALSO CLIPS FRANKLIN, ADAMS,
AND YORK COUNTIES, VALID THROUGH MIDNIGHT. CONFIDENCE IN SEVERE
WEATHER MAKING IT THIS FAR NORTH IS LOW, HOWEVER, WITH MLCAPE
SUB 1000 J/KG, DCAPE SUB 500 J/KG, AND EFFECTIVE SHEAR SUB 25
KTS. EFFECTIVE SHEAR WILL RISE A BIT AFTER MIDNIGHT, POTENTIALLY
BRINGING ABOUT MORE ORGANIZED CONVECTION (MORE OF A HEAVY RAIN
THREAT), BUT AT THE SAME TIME DECREASING INSTABILITY WILL LEAD
TO A DECREASING THREAT FOR SEVERE WEATHER.
WE WILL CONTINUE TO MONITOR THE THREAT FOR LOCALIZED FLOODING
OVERNIGHT. FLASH FLOOD WARNINGS HAVE BEEN ISSUED FOR PORTIONS
OF TIOGA AND BRADFORD COUNTIES WHERE MODERATE TO HEAVY
STRATIFORM RAIN OVER THE PAST FEW HOURS HAS PUSHED RAINFALL
TOTALS LOCALLY ABOVE 2 INCHES. THE THREAT AREA FOR RAPID ONSET
FLOODING WILL EXPAND BETWEEN 10 PM AND DAYBREAK AS THE NEXT
BATCH OF CONVECTION MOVES NORTH FROM MARYLAND, INTO CENTRAL PA
WITH THE HEAVIEST RAIN (A STRIPE OF 1.00-1.50 INCHES) EXPECTED
FROM FRANKLIN/ADAMS COUNTIES NORTH INTO MIFFLIN/CENTRE AND
FARTHER NORTH INTO POTTER/TIOGA. THE RISK OF FLOODING IS STILL
NOT HIGH ENOUGH TO WARRANT A FLOOD WATCH AT THIS TIME.
SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/
ACTIVE WEATHER WILL LIKELY CONTINUE TUESDAY/TUESDAY EVENING AS
THE CORE OF THE UPPER LOW MOVES INTO WESTERN PA. THIS WILL PUSH
THE HIGHEST INSTABILITY AND GREATEST CHANCE FOR SEVERE WEATHER
EAST INTO THE SUSQUEHANNA VALLEY. A MRGL RISK OF SEVERE WEATHER
IN PLACE EAST OF STATE COLLEGE AND NORTH OF I-76/PA TURNPIKE
INTO NY/NJ. RAINFALL AMOUNTS SHOULD BE LOWER ON TUESDAY COMPARED
TO TODAY, WITH ENSEMBLE MEAN ACCUMULATIONS LESS THAN 1 INCH.
THE THREAT FOR SEVERE WEATHER APPEARS TO DECREASE WEDNESDAY AS
THE SLOW MOVING UPPER LOW GRADUALLY FILLS IN AND THE CENTER
MOVES ACROSS THE EASTERN THIRD OF THE STATE IN THE AFTERNOON,
WITH PRECIP LIKELY COMING TO AN END ACROSS THE BULK OF CENTRAL
PA BY WED AFTERNOON OR EARLY EVENING. UPSLOPE/LAKE ENHANCED
SHOWERS MAY LINGER A BIT LONGER IN THE NORTHWEST MOUNTAINS WITH
NORTHWEST FLOW BUILDING IN BEHIND THE DEPARTING LOW.
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/
UPPER LOW WILL BE GETTING KICKED OUT BY A LONG WAVE TROUGH
SWINGING DOWN FROM THE GREAT LAKES VERY EARLY IN THE PERIOD.
DRIER AIR ON THURS SHOULD KEEP SHRA FROM BEING AS NUMEROUS AND
CERTAINLY AS STRONG/RAINY AS THE EARLY WEEK SHOWERS/STORMS.
30-50 POPS SHOULD BE OK FOR THURS-THURS EVENING. THIS UPPER
TROUGH SHOULD BE PROGRESSING THRU BUT MAY ALSO SLOW DOWN JUST
AFTER IT PASSES OUR LONGITUDE. THUS, WE WILL HAVE TO LINGER A
LOW CHC POP ON FRI-FRI NIGHT. WEAK HIGH PRESSURE WILL THEN MOVE
IN FOR THE WEEKEND. WE MAY STILL HOLD ONTO A 20 POP FOR THOSE
DAYS THOUGH. SEE NO REASONS TO STRAY FROM THE NBM GUIDANCE ON
THE WHOLE. MINOR TWEAKS ONLY TO MAKE POPS AND QPF MATCH UP.
AVIATION /00Z TUESDAY THROUGH SATURDAY/
VARIABLE CEILINGS, THOUGH GENERALLY MVFR TO VFR CONDITIONS,
ACROSS CENTRAL PA AS UPPER LOW SPINS OVER THE OHIO VALLEY,
BRINGING MOIST SE FLOW AND INCREASING AMOUNTS OF SHOWERS ALONG
WITH SCATTERED THUNDERSTORMS. CURRENTLY IN A LULL FROM
THUNDERSTORM ACTIVITY WITH JUST RAIN SHOWERS ACROSS THE
AIRSPACE. ANOTHER WAVE OF MORE WIDESPREAD SHOWERS / SCATTERED
THUNDERSTORMS WILL LIFT NORTH ACROSS THE AIRSPACE BETWEEN 01-06Z
THIS EVENING, ACCOMPANIED BY A DROP IN CEILINGS PRODUCING
WIDESPREAD IFR CONDITIONS THAT WILL LINGER INTO EARLY TUES.
BEST ESTIMATE IS THE AOO/UNV/JST WILL HAVE BEST CHANCE OF
SEEING A TSRA WITH GUSTY WINDS AND SMALL HAIL AND OR HEAVY RAIN
IN THIS TIME PERIOD AS A DEVELOPING LINE OF STORMS LIFTS NWD
FROM MD?VA AIRSPACE.
CONDITIONS LOOK TO IMPROVE ONLY SLIGHTLY ON TUE, BUT AFTER A
SHORT BREAK IN THE WET WEATHER, ADDITIONAL SHOWERS/TSTMS
EXPECTED IN THE AFTERNOON/EVENING WITH CONTINUED RESTRICTIONS.
OUTLOOK...
TUE...FREQUENT RAIN SHOWERS; SOME LOCALLY HEAVY WITH PROLONGED
SUB-VFR CONDITIONS. CHANCE OF TSRA/CB.
WED-FRI...SHOWERS BECOME MORE SCATTERED WITH HIGHER CHANCES IN
THE AFTERNOON/EVENING HOURS. RESTRICTIONS POSSIBLE.
SAT...NO SIG WX.
CTP WATCHES/WARNINGS/ADVISORIES
NONE.
SYNOPSIS...BANGHOFF/COLBERT
NEAR TERM...BANGHOFF/COLBERT
SHORT TERM...LAMBERT/BANGHOFF
LONG TERM...DANGELO
AVIATION...GARTNER/RXR
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page