031
FXUS61 KCTP 200115
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
915 PM EDT TUE MAY 19 2026
WHAT HAS CHANGED
* LITTLE THREAT FOR WIND GUSTS OVER 40 KTS EARLY TONIGHT ACROSS
NW PA WITH THE LINE OF SHRA/TSRA WELL IN ADVANCE OF A COLD
FRONT.
* INCREASING ODDS FOR A NOTICEABLY COOLER AND RATHER WET START
TO MEMORIAL DAY WEEKEND (LOWERED MAX TEMPS FOR SAT BY SEVERAL
DEG F WITH EXTENSIVE LOW CLOUDS, LLVL EASTERLY FLOW AND
PERIODS OF RAIN/DRIZZLE/RIDGE SHROUDING FOG.
KEY MESSAGES
1) SCATTERED STRONG THUNDERSTORMS ARE POSSIBLE ACROSS THE NW
MTNS EARLY TONIGHT, THEN ACROSS SOUTH CENTRAL PA AND THE LOWER
SUSQ VALLEY WEDNESDAY AFTERNOON
2) MAJOR COOLDOWN ARRIVES THURSDAY AND LASTS INTO MEMORIAL DAY
WEEKEND WITH WIDESPREAD SOAKING RAINFALL (OVER 1 INCH) LIKELY
FRIDAY AND SATURDAY
DISCUSSION
KEY MESSAGE 1: SCATTERED STRONG THUNDERSTORMS ARE POSSIBLE ACROSS
THE NW MTNS EARLY TONIGHT, THEN ACROSS SOUTH CENTRAL PA AND THE
LOWER SUSQ VALLEY WEDNESDAY AFTERNOON
SPC TRIMMED BACK ITS SLGT RISK AREA FOR SVR OUT OF NW PA WITH
ITS 0045Z UPDATE.
A WEAKENING LINE OF SHOWERS AND THUNDERSTORMS WILL BE MOVING
ACROSS OUR NW MTN ZONES BETWEEN 02-05Z WITH SOME WIND GUSTS OF
35-40 KTS POSSIBLE, MORE SO ACROSS THE REGION SOUTH OF ROUTE 6
WHERE THE BEST COMBINATION OF SFC BASED CAPE OVER 1000 J/KG AND
DCAPE OF ~1000 J/KG WILL EXIST.
ELSEWHERE ACROSS CENTRAL PA AND THE SUSQ VALLEY, EXPECT A PARTLY
TO MOSTLY CLOUDY AND RATHER MUGGY NIGHT WITH SFC TDS IN THE LOW
TO MID 60S IN MOST PLACES. MORE COMFORTABLE CONDITIONS WILL
OCCUR ACROSS THE NW MTNS WHERE RAIN-COOLED AIR AND SFC DEWPOINTS
ONLY AROUND 60F WILL BE FOUND.
DUAL TO MULTI-LAYERED CLOUDS WITH JUST SOME WIDELY SCATTERED
LIGHT SHOWERS WEDNESDAY MORNING WILL BE FOLLOWED BY A FEW
PERIODS OF SHOWERS IN THE EARLY-MID AFTERNOON, NEAR AND TO THE
NORTH OF I-80.
CONVECTIVE FOCUS SHIFTS TO SOUTH CENTRAL PA WEDNESDAY AFTERNOON
WITH NARROW PLUME OF WEAK TO MODERATE CAPE FCST AHEAD OF THE
AFOREMENTIONED COLD FRONT. STEEP LOW LEVEL LAPSE RATES MAY
SUPPORT A FEW INSTANCES OF STRONG TO SEVERE WINDS. THE MAGNITUDE
& LOCATION OF THE SEVERE THREAT WILL BE HIGHLY DEPENDENT ON
CFROPA TIMING AND AMOUNT OF CLOUD COVER. SPC MRGL RISK (LEVEL
1/5) COVERS THE SOUTHEAST HALF OF THE CWA WHERE MAX TEMPS ARE
FCST BTWN 80-90F.
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KEY MESSAGE 2: MAJOR COOLDOWN ARRIVES THURSDAY AND LASTS INTO
MEMORIAL DAY WEEKEND WITH WIDESPREAD SOAKING RAINFALL LIKELY
FRIDAY AND SATURDAY
RELIEF FROM THE EARLY SEASON HEAT WAVE ARRIVES IN EARNEST ON
THURSDAY WITH MAX TEMPS 20-30 DEGREES LOWER VS. WEDNESDAY ACROSS
THE SOUTHEAST HALF OF THE FORECAST AREA. STRONG HIGH PRESSURE
SLIDES FROM THE LOWER GREAT LAKES TO OFF THE NEW ENGLAND COAST
TO CLOSE OUT THE WEEK. MODEL DATA SHOWS THE HIGH CHANNELING
SOUTHWARD DOWN THE EAST-SIDE OF THE APPALACHIANS, SETTING UP A
COLD AIR DAMMING TYPE EVENT HEADING INTO MEMORIAL DAY WEEKEND.
EARLIER SHIFTS NOTED, "WE MAY NOT BE BEARISH ENOUGH ON DAYTIME
TEMPERATURES." DID TRIM MAX TEMPS SATURDAY DOWN BY 4-5 DEG F
GIVEN THE THICK CLOUDS, MODERATELY STRONG EAST-SERLY LLVL FLOW
AND PERIODS OF SOAKING RAIN THAT WILL DAMPEN AT LEAST THE START
OF THE HOLIDAY WEEKEND. WPC 48HR QPF AMOUNTS ARE QUITE WET WITH
A WIDESPREAD 1-2.5 INCHES FCST FROM 12Z FRIDAY TO 12Z SUNDAY.
AVIATION /00Z WEDNESDAY THROUGH SUNDAY/
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR THIS HOT AFTERNOON.
WINDS HAVE BECOME GUSTY WITH DAYTIME HEATING AND RIDGING
BUILDING FROM OUR SOUTH, GUSTS COULD REACH UP TO 25KTS.
CONVECTION IS ALREADY BEING OBSERVED OVER THE SOUTHWESTERN
AIRFIELDS, BUT FORCING IS WEAK MAKING COVERAGE AND STRENGTH OF
THESE STORMS UNCERTAIN FOR THE REMAINDER OF TODAY. INSTABILITY
IS HIGH ENOUGH THAT ANY STORM THAT DOES DEVELOP WILL LIKELY
CONTAIN LIGHTNING UNTIL AFTER SUNDOWN. THE MOST LIKELY AIRFIELDS
TO BE IMPACT BY THESE STORMS THROUGH 00Z WILL BE JST AND AOO.
TONIGHT, THE LOW PRESSURE SYSTEM OVER THE GREAT LAKES WILL
APPROACH FROM THE NORTHWEST. THIS WILL CAUSE CEILINGS TO LOWER
AND BRING ADDITIONAL RAIN CHANCES FROM NORTHWEST TO SOUTHEAST
FOR THE DAY ON WEDNESDAY. MVFR CEILINGS ARE LIKELY AHEAD OF THE
COLD FRONT AT BFD, JST, AOO, UNV, AND IPT. THE ONLY SITE LIKELY
TO EXPERIENCE IFR CEILINGS WILL BE BFD EARLY TOMORROW MORNING,
ELSEWHERE SHOULD REMAIN MVFR OR BETTER.
LASTLY, LLWS MENTIONS WERE INCLUDED AT OUR NORTHERN TERMINALS
(KBFD/KIPT) THROUGH THE EVENING/OVERNIGHT HOURS AS 900 MB WINDS
INCREASE TO AROUND 40 KTS DUE TO PRESSURE GRADIENT BETWEEN LOW
PRESSURE OVER SOUTHERN CANADA & BERMUDA HIGH OVER THE WESTERN
ATLANTIC.
OUTLOOK...
WED...RESTRICTIONS PROBABLE THROUGH WEDNESDAY NIGHT WITH
WIDESPREAD SHOWERS/STORMS ALONG CFROPA.
THU...LINGERING SHOWERS ACROSS S PA, RESTRICTIONS POSSIBLE.
FRI...RESTRICTIONS LIKELY WITH RAIN MOVING IN FROM SOUTH TO
NORTH, LASTING INTO FRI NIGHT.
SAT-SUN...RESTRICTIONS LIKELY WITH RAIN.
CLIMATE
THE FOLLOWING CLIMATE SITES ACROSS CENTRAL PENNSYLVANIA SET NEW
DAILY HIGH TEMPERATURE RECORDS FOR MAY 18TH:
* A RECORD HIGH TEMPERATURE OF 92 DEGREES WAS SET IN ALTOONA,
BREAKING THE PREVIOUS RECORD OF 91 DEGREES INITIALLY SET BACK
IN 1962. THIS RECORD WAS TIED TWO TIMES PREVIOUSLY, BACK IN
1996 AND 2017.
* A RECORD HIGH TEMPERATURE OF 86 DEGREES WAS SET IN BRADFORD,
BREAKING THE PREVIOUS RECORD OF 85 DEGREES SET BACK IN 1962.
** NOTE: THE HIGH TEMPERATURE FOR STATE COLLEGE WILL BE REPORTED
AROUND 7AM ON 5/19. THIS IS DUE TO THE STATE COLLEGE CO-OP
OBSERVATIONS RUNNING 7AM-7AM. THUS, TODAY'S (5/18) HIGH
TEMPERATURE WILL BE REPORTED IN TOMORROW'S (5/19) OBSERVATION.
THIS RECORD, FOR REFERENCE, IS 92 DEGREES SET IN 1962.
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ABNORMALLY WARM TEMPERATURES WILL CONTINUE ON MAY 19TH, THUS
MULTIPLE SITES COULD CHALLENGE DAILY RECORD HIGH TEMPERATURES.
DAILY MAXIMUM HIGH TEMPERATURES FOR MAY 19TH:
* HARRISBURG: 95F SET IN 1962
* WILLIAMSPORT: 96F IN IN 1996
* ALTOONA: 92F SET IN 1996
* BRADFORD: 85F SET IN 1962
* STATE COLLEGE: 92F SET IN 1934, TIED IN 1996.
CTP WATCHES/WARNINGS/ADVISORIES
NONE.
WHAT HAS CHANGED...LAMBERT/STEINBUGL/BAUCO
KEY MESSAGES...LAMBERT/STEINBUGL/BAUCO
DISCUSSION...LAMBERT/STEINBUGL/BAUCO
AVIATION...BOWEN
CLIMATE...BEATY
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