105
FXUS61 KCTP 211033
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
633 AM EDT SAT MAR 21 2026
WHAT HAS CHANGED
DENSE FOG ADVISORY FOR A PORTION OF EAST-CENTRAL PA UNTIL 8AM
SEVERE THUNDERSTORM RISK LEVEL INCREASED FROM 1 TO 2 FOR SUNDAY
OVER SOUTH CENTRAL PA
KEY MESSAGES
1) LOW VISIBILITY IN DENSE FOG COULD MAKE DRIVING HAZARDOUS
EARLY THIS MORNING ACROSS PORTIONS OF EAST-CENTRAL PA
2) FIRST WEEKEND OF SPRING WARMUP PRECEDES RAIN AND SEVERE
THUNDERSTORM RISK SUNDAY AFTERNOON INTO SUNDAY NIGHT
DISCUSSION
KEY MESSAGE 1: LOW VISIBILITY IN DENSE FOG COULD MAKE DRIVING
HAZARDOUS EARLY THIS MORNING ACROSS PORTIONS OF EAST-CENTRAL PA
TEMPORARY CLEARING IN THE WAKE OF YESTERDAYS RAINFALL HAS
RESULTED IN PATCHY TO LOCALLY DENSE FOG FORMATION ACROSS
PORTIONS OF EAST CENTRAL PA. VISIBILITY TRENDS HAVE BEEN
IMPROVING ON THE MARGIN UPON THE ARRIVAL OF LOWER CLOUD DECK
CONTINUING TO EXPAND SOUTHEASTWARD PER IR SATELLITE IMAGERY.
COORDINATED WITH PHI ON ISSUANCE OF DFA UNTIL 8AM WITH SEVERAL
ASOS AND RWIS SITES REPORTING VISBY BELOW 1000FT OR <1/4 MILE.
KEY MESSAGE 2: FIRST WEEKEND OF SPRING WARMUP PRECEDES RAIN AND
SEVERE THUNDERSTORM RISK SUNDAY AFTERNOON INTO SUNDAY NIGHT
A NICE START TO SPRING THIS WEEKEND WITH FCST HIGHS RAMPING 15
TO 30F ABOVE THE HISTORICAL AVERAGE BY SUNDAY. THIS SURGE OF
WARMTH WILL BE BRIEF AND FOLLOWED BY A NOTICEABLE COOLDOWN ON
MONDAY WITH MAX TEMPS 20-30 DEGREES LOWER THAN SUNDAY.
SPC EXPANDED THE LEVEL 2/SLIGHT RISK OUTLOOK FROM THE UPPER
OHIO VALLEY INTO SOUTH CENTRAL PA (SOUTH OF I-80) FOR SUNDAY
AFTERNOON AND EVENING. CAPE AND 0-6KM SHEAR PROFILES APPEAR
RATHER FAVORABLE FOR ORGANIZED SEVERE STORMS AHEAD OF A
SOUTHEASTWARD ADVANCING COLD FRONT. LARGE HAIL PROBS ARE
RELATIVELY HIGH WITH 700-500MB LAPSE RATES 7-7.5 C/KM AND
ESSENTIALLY MATCH THE DAMAGING WIND PROBS.
SECONDARY FRONTAL WAVE DEVELOPMENT NEAR THE DELMARVA/SRN NJ
SHOULD HOLD UP THE COLD FRONT AND ALLOW COLDER TEMPS TO
BLEED/CREEP SOUTHWARD LATE SUNDAY NIGHT INTO MONDAY MORNING.
THIS SHOULD RESULT IN A RAIN/SNOW MIX OR CHANGEOVER TO WET SNOW
ALONG THE NORTHERN EDGE OF THE FRONTAL PRECIP BAND AS IT EXITS
THE AREA. A COATING OF SNOW UP TO 0.5" IS MOST LIKELY ON NON-
PAVED SFCS ACROSS THE NORTHERN TIER BY 12Z MONDAY. HIGH TEMPS
ON MONDAY ARE PROJECTED TO BE 20 TO 30 DEGREES COLDER THAN
SUNDAY, PUNCTUATED BY A CHILLY AND BRISK/GUSTY NW WIND.
THE REST OF NEXT WEEK SHOULD FEATURE MORE TEMPERATURE SWINGS UP
AND DOWN WITH OCCASIONAL LIGHT PRECIP. THE BEST PRECIP SIGNAL IN
THE 21/00Z MODEL CYCLE IS IN THE LATE THURSDAY/THURSDAY NIGHT
TIMEFRAME.
AVIATION /12Z SATURDAY THROUGH WEDNESDAY/
MIXED BAG OF OBSERVATIONS ACROSS CENTRAL PENNSYLVANIA THIS
MORNING WITH FOG ACROSS SE PA AND LOWER CEILINGS BRINGING
BORDERLINE MVFR-IFR CEILINGS ELSEWHERE AS OF 10Z. ALL MODEL
GUIDANCE POINTS TO WIDESPREAD IMPROVEMENT TOWARDS VFR AFTER 12Z
SATURDAY. RECENT MODEL GUIDANCE TRENDS MORE OPTIMISTIC WITH
RESPECT TO CONDITIONS AT MOST AIRFIELDS (OUTSIDE OF BFD)
REACHING VFR THRESHOLDS BY 15-16Z SATURDAY, WHICH SEEMS
PLAUSIBLE. THE MAIN DEVIATION FROM MODEL GUIDANCE AND PREVIOUS
FORECAST WAS TO KEEP BFD DOWN AN EXTRA HOUR OR TWO DUE TO MODEL
GUIDANCE TYPICALLY BEING TOO OPTIMISTIC HERE FOR IMPROVEMENT IN
CEILINGS. BETWEEN 18Z SAT AND 06Z SUN, VFR CONDITIONS ARE
VIRTUALLY CERTAIN ACROSS ALL OF CENTRAL PENNSYLVANIA.
MODEL GUIDANCE CONTINUES TO PAINT ALL AIRFIELDS OUTSIDE OF
MDT/LNS FOR CONTINUED VFR CONDITIONS, WITH THE MAIN CONCERN
BEING LLWS ACROSS W PA. LLWS CONCERNS HAVE SEEN AN UPTICK IN
THIS REGION, SO HAVE DECIDED TO GO AHEAD AND INCLUDE MENTIONS
EVEN THOUGH THESE CONCERNS ARE OVER TWELVE HOURS OUT, GIVEN THE
ARRIVAL OF A 40-50KT LLJ ACROSS THE REGION. FURTHER SOUTHEAST AT
MDT/LNS, SOUTHERLY FLOW WITH AN EXTREMELY SLIGHT EASTERLY
COMPONENT COULD ALLOW FOR SOME MOISTURE FOR REACH INTO THE
FURTHEST REACHES OF THE LOWER SUSQUEHANNA VALLEY, MAINLY AFTER
08Z SUNDAY. THIS WOULD BRING IN LOWER CEILINGS WITH SLIGHTLY
LOWER POTENTIAL FOR LOWER VISIBILITIES MANIFESTING; HOWEVER,
HAVE KNOCKED THESE DOWN SOME TO KEEP TRENDED WITH GLAMP MODEL
GUIDANCE WHICH APPEARS TO BE ONTO THE SAME IDEA. ALTERNATIVE
SCENARIOS OF VFR CONTINUING ARE MOST LIKELY AT MDT, WITH HIGHER
PROBABILITIES AND CONFIDENCE IN THE LOWER CEILING SCENARIO
PLAYING OUT AT LNS BETWEEN 08Z-12Z SUN.
OUTLOOK...
SUN...RAIN OVERSPREADS NORTH TO SOUTH, RESTRICTIONS POSSIBLE.
MON...RAIN GRADUALLY TAPERS OFF NORTH TO SOUTH, TRANSITION TO
SNOW POSSIBLE MAINLY NORTH OF I-80 (BFD/IPT). RESTRICTIONS
POSSIBLE WITHIN RAIN/SNOW SHOWERS.
TUE...MAINLY DRY WITH VFR CONDITIONS. SLIGHT CHANCE OF SNOW
SHOWER ACROSS NORTHERN PA LATE WHICH COULD BRING SOME
RESTRICTIONS.
WED...RAIN AND SNOW SHOWERS ACROSS NORTHERN PA WITH
RESTRICTIONS POSSIBLE.
CLIMATE
DAILY RECORD HIGH TEMPERATURES FOR MARCH 22:
HARRISBURG 80 IN 1938
WILLIAMSPORT 82 IN 1938
ALTOONA 81 IN 1966
STATE COLLEGE 80 IN 1938
CTP WATCHES/WARNINGS/ADVISORIES
DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR PAZ028-
049>053-056>059-063>066.
WHAT HAS CHANGED...STEINBUGL
KEY MESSAGES...STEINBUGL
DISCUSSION...STEINBUGL
AVIATION...BEATY
CLIMATE...STEINBUGL
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