761
FXUS61 KCTP 240840
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
440 AM EDT FRI JUL 24 2026
WHAT HAS CHANGED
NO SIGNIFICANT CHANGES OTHER THAN FOCUSING THE GREATEST PROBS
FOR SHOWERS/TSRA MONDAY AFTERNOON THROUGH TUESDAY.
KEY MESSAGES
1) PLEASANT/DRY PATTERN WITH COMFORTABLY LOW DAYTIME HUMIDITY
CONTINUES INTO THE LAST WEEKEND OF JULY.
2) TURNING MORE HUMID WITH SEVERAL ROUNDS SHOWERS AND THUNDERSTORMS
NEXT WEEK. PERHAPS A FEW STRONG STORMS WITH HEAVY RAIN AT
TIMES.
DISCUSSION
KEY MESSAGE 1: PLEASANT/DRY PATTERN WITH COMFORTABLY LOW DAYTIME
HUMIDITY CONTINUES INTO THE LAST WEEKEND OF JULY.
SURFACE HIGH PRESSURE EXTENDING FROM THE LOWER GREAT LAKES TO
THE NEW ENGLAND STATES WILL BRING ANOTHER SEVERAL DAYS OF VERY
PLEASANT MID SUMMER CONDITIONS WITH ABUNDANT SUNSHINE TODAY AND
A MIX OF SUN AND CLOUDS FOR SATURDAY AND SUNDAY.
WHILE THERE COULD BE ONE OR TWO HIGHLY ISOLATED SHOWERS OR
A THUNDERSTORM OVER THE REGION LATE THIS WEEKEND (MAINLY OVER
WESTERN PORTIONS OF THE STATE), THE AIRMASS REMAINS QUITE DRY.
HIGH TEMPERATURES TODAY AND SATURDAY WILL RANGE FROM THE MID TO
UPPER 70S ACROSS THE HIGHER TERRAIN, TO THE LOW 80S IN THE
CENTRAL AND SOUTHERN VALLEYS.
KEY MESSAGE 2: TURNING MORE HUMID WITH SEVERAL ROUNDS OF SHOWERS
AND THUNDERSTORMS NEXT WEEK. PERHAPS A FEW STRONG STORMS LATE
MONDAY AND TUESDAY AFTERNOON/EVENING.
HIGHLY DIFFLUENT NORTHWESTERLY FLOW ACCENTUATED BY A FEW
SHORTWAVES DROPPING SOUTHEAST ACROSS THE GREAT LAKES REGION
WILL LEAD TO AN INCREASING PROBABILITY FOR SHOWERS AND
THUNDERSTORMS. THE HIGHEST CHANCE FOR CONVECTION WILL COME
MONDAY AFTERNOON AND EVENING AND AGAIN ON TUESDAY AS A FAIRLY
COMPACT, BUT POTENT MID AND UPPER LEVEL SHORT WAVE DIGS SE AND
AMPLIFIES SIGNIFICANTLY AS IT REACHES OUR LONGITUDE.
THE INITIAL ROUND OF SHRA/TSRA WILL TRACK SE ALONG A SLOW-MOVING
WARM FRONT AND COULD BE ON THE STRONG TO SEVERE SIDE LATE
MONDAY/MON EVENING ACROSS PARTS OF CENTRAL AND WESTERN PA
WPC HAS A BROAD LEVEL 1/4 MARGINAL EXCESSIVE RAIN RISK FOR
D5/MONDAY JULY 27 THAT COVERS MOST OF CPA.
SFC LOW TRACKING FROM LAKE SUPERIOR ON MONDAY AND DEEPENING BY
ABOUT 6 MB (TO AROUND 995 MB) BY THE TIME IT REACHES LAKE
ONTARIO AT 18Z TUESDAY WILL HELP TO FOCUS TSRA IN PA DURING THE
DAY TUESDAY ALONG, AND AHEAD OF A SURFACE COLD FRONT (THAT WILL
BE OVER NW PA LATE TUESDAY MORNING WITH A WELL-DEFINED LEE
TROUGH EXTENDING DOWN THE SUSQ AND DELAWARE VALLEYS TUES
AFTERNOON/EARLY EVENING).
AVIATION /07Z FRIDAY THROUGH TUESDAY/
VFR CONDITIONS ARE GENERALLY EXPECTED THROUGHOUT THE 06Z TAF
PACKAGE WITH HIGH (> 90%) CONFIDENCE AT ALL AIRFIELDS OUTSIDE OF
BFD WHERE SOME LOWER VISIBILITY RESTRICTIONS WILL BE POSSIBLE
IN THE 08-12Z FRIDAY TIMEFRAME. CURRENT ECONUS NIGHTTIME
MICROPHYSICS OUTLINES THE TYPICAL DENDRITIC VALLEY FOG DUE TO
CLEAR SKIES AND CALM WINDS DESPITE THE RELATIVELY DRY AIR MASS
FOR THIS TIME OF THE YEAR. DEWPOINT DEPRESSION AT BFD REMAIN
STOUT AT 2F; HOWEVER, SEEING INCREASING COVERAGE OF FOG AROUND
THE ENTIRE TAF SITE. AT THIS TIME, THE BULK OF LOWER VISIBILITY
RESTRICTIONS WILL LIKELY STAY *JUST* OUTSIDE OF THE TERMINAL
WITH SOME VICINITY FOG LIKELY BEGINNING TO MAKE WAY OVER THE
NEXT HOUR OR TWO. RECENT GLAMP MODEL GUIDANCE DOES OUTLINE IFR
VISIBILITIES BUT COULD SEE MVFR BEING A SLIGHTLY MORE LIKELY
OUTCOME AT THIS TIME GIVEN THAT VISIBILITIES APPEAR TO BE
VERIFYING CLOSER TO THE MINIMUM HREF MEMBERS AS OF 2AM. IF THIS
VERIFIES, VISIBILITIES NEAR-OR-BELOW 2SM WILL BE POSSIBLE
BETWEEN 09-11Z BEFORE RAPID IMPROVEMENT TOWARDS VFR OCCURS BY
13Z FRIDAY.
AFTER 13Z FRIDAY, VFR CONDITIONS ARE VIRTUALLY CERTAIN ACROSS
ALL OF CENTRAL PENNSYLVANIA'S TERMINALS. HIGH CLOUDS AND LIGHT
WINDS ARE EXPECTED THROUGHOUT THE DAY WITH SOME LOWER-LEVEL
CLOUDS PROGGED BY MODEL GUIDANCE ALONG THE RIDGETOPS, THUS HAVE
OUTLINED SOME SCATTERED LOWER-LEVEL CLOUDS AT JST/AOO WHERE THIS
IS MOST LIKELY TO BE OBSERVED. SKIES CLEAR OUT WITH LIGHT WINDS
TRENDING TOWARDS CALM TOWARDS THE END OF THE 06Z TAF PACKAGE,
WHICH WILL BRING SOME POTENTIAL FOR VALLEY FOG TOMORROW NIGHT;
HOWEVER, SIGNALS APPEAR TO BE MORE CONFINED TO NE PA.
OUTLOOK...
SAT...GENERALLY VFR CONDITIONS WITH LOW-END (< 20%) CHANCE OF AN
AFTERNOON SHOWER/STORM ACROSS WESTERN SECTIONS OF CENTRAL PA.
SUN...INCREASING CHANCES OF PM SHOWERS/STORMS, WITH SOME
RESTRICTIONS POSSIBLE.
MON-TUE...RESTRICTIONS POSSIBLE IN SHOWERS/STORMS.
CLIMATE
MULTIPLE RECORD LOW TEMPERATURES WERE SET FOR JULY 23RD ACROSS
CENTRAL PENNSYLVANIA:
* ALTOONA SET A RECORD LOW TEMPERATURE OF 47 DEGREES WAS SET,
BREAKING THE PREVIOUS RECORD OF 50 DEGREES SET BACK IN 1981.
* BRADFORD TIED A RECORD LOW TEMPERATURE OF 38 DEGREES WHICH
WAS PREVIOUSLY SET IN 1981.
* JOHNSTOWN TIED A RECORD LOW TEMPERATURE OF 49 DEGREES WHICH
WAS PREVIOUSLY SET IN 1983.
CTP WATCHES/WARNINGS/ADVISORIES
NONE.
WHAT HAS CHANGED...LAMBERT
KEY MESSAGES...LAMBERT
DISCUSSION...LAMBERT
AVIATION...BEATY
CLIMATE...BEATY
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