255
FXUS61 KCTP 201924
AFDCTP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
224 PM EST THU FEB 20 2025
SYNOPSIS
AN UPPER LEVEL LOW WILL TRACK ACROSS PENNSYLVANIA TODAY, THEN A
MORE ZONAL PATTERN WILL DEVELOP OVER THE CONUS THIS WEEKEND. A
WEAK SHORTWAVE AND ASSOCIATED COLD FRONT IS LIKELY TO PUSH
THROUGH THE REGION TUESDAY OF NEXT WEEK.
NEAR TERM /THROUGH TONIGHT/
LARGER SHIELD OF LIGHT SNOW HAS BECOME A BROAD AREA OF CELLULAR
CONVECTION/SHSN AS THE UPPER LOW HAS MOVED RIGHT OVERHEAD AT
19Z. THE FLOW SHOULD ALIGN BETTER LATER TODAY AND THIS EVENING,
AND COULD MAKE MORE IN THE WAY OF BANDED STRUCTURES. SOME ARE
PROGGED TO GET DOWN INTO LNS LATE IN THE AFTN AND EARLY
EVENING. HOWEVER, ACCUMULATIONS THERE SHOULD JUST BE A DUSTING.
6 HRS OF -SN (GENERALLY 2-4SM VISBY) IN STATE COLLEGE WITH
SUB-20F TEMPS HAS YIELDED THE TINIEST AMOUNT OF SNOW
ACCUMULATION IN THE MULCH AND GRASS, AND ONLY WET SIDEWALKS AND
ASPHALT. THE INCREASING SUN ANGLE IS LIKELY HELPING THINGS STAY
LAME. SOME ACCUMS ON THE ROADS ARE SEEN ON THE HIGHER
ELEVATIONS ON I-80 AND IN THE LAURELS. EXPECT THE DOWNSLOPING TO
WIN OUT THIS EVENING AND DRY THINGS UP DOWNHILL OF THE OL' AOO-
UNV-IPT LINE. THE DRY LLVLS WILL ALSO MAKE IT TOUGH TO GET MUCH
ACCUMULATION. ADDITIONAL ACCUMS OF 1-2" ARE EXPECTED IN THE
LAURELS, MAINLY SOMERSET CO. THIS IS (JUST) ENOUGH TO JUSTIFY
CONTINUING THE ADVY THERE.
THE GUSTY NW WIND WILL BRING WIND CHILLS DOWN TO BETWEEN -5F
AND +5F ACROSS THE BOARD. A FEW PIXELS OF -10F ARE SEEN OVER
POTTER AND SOMERSET COUNTIES, BUT NOT NEARLY ENOUGH COVERAGE OF
THESE LOW VALUES TO WARRANT A COLD WEATHER ADVY (POTTER NEEDS
TO GET TO -15F ANYWAY).
SHORT TERM /FRIDAY/
GUSTS INTO THE 20S AND 30S (AND 40-ISH ON THE HILLTOPS OF THE
LAURELS) WILL CONTINUE FOR THE WHOLE DAYTIME, DESPITE A FALLING
INVERSION SINCE THE WINDS AT THE TOP OF THE MIXED LAYER WILL
CONTINUE TO BE STRONG. THE SNOW SHOULD DIMINISH IN THE MORNING
OVER THE WEST WITH NO ADDITIONAL ACCUMS. CLEARING OVER MUCH OF
THE AREA WILL TEAM UP WITH THE DOWNSLOPE TO BUMP MAX TEMPS 5-6F
OVER THURS VALUES IN THE SE, BUT ONLY A DEG OR SO NW.
LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/
SURFACE RIDGE AXIS WILL RIPPLE THROUGH CPA FRIDAY NIGHT AND
SATURDAY. FRIDAY NIGHT WILL MARK A SHORT TERM BOTTOM FOR TEMPS
WITH LOWS IN THE +SINGLE DIGITS AND TEENS. LOW LEVEL MOISTURE
TRAPPED BENEATH A SUBSIDENCE INVERSION MAY YIELD LINGERING LOW
CLOUDS ACROSS THE NW MTNS AND LAUREL HIGHLANDS FRIDAY NIGHT INTO
EARLY SATURDAY. OTHERWISE, MODEL RH PROFILES SUPPORT A PARTLY
TO MOSTLY SUNNY START TO THE LAST WEEKEND OF FEBRUARY WITH MAX
TEMPS CLIMBING +10 DEGREES DAY OVER DAY (VS. FRIDAY) INTO THE
30-40F RANGE.
KEY TAKEAWAYS: SATURDAY, FEBRUARY 22 - THURSDAY, FEBRUARY 27
------------------------------------------------------------
*WARMING TREND TO NEAR/ABOVE HISTORICAL AVERAGES TO END FEBRUARY
*NO PRECIPITATION FOR THE LAST WEEKEND OF FEBRUARY
*QUICK MOVING SYSTEMS BRING PASSING RAIN/SNOW SHOWERS MON-TUE
*HIGHEST PROBABILITY & CONFIDENCE IN WIDESPREAD PRECIP THU-FRI
DRY WEATHER AND MODERATING TEMPERATURES [WARMING TREND] EXPECTED
FOR THE LAST WEEKEND OF FEBRUARY 2025. THERE WILL BE INTERVALS
OF CLOUDS AND SUN WITH MORE SUNSHINE IN THE SOUTH/EASTERN PART
OF THE FORECAST AREA.
A PAIR OF FAST MOVING NORTHERN STREAM SHORTWAVES WILL BRING
PASSING RAIN/SNOW SHOWERS EARLY NEXT WEEK. SNOW SHOWERS ARE
MOST LIKELY OVER THE HIGHER ELEVATIONS WITH RAIN SHOWERS IN THE
VALLEYS. MAX POPS ARE ON TUESDAY BASED ON NBM AND EC/CMC/GFS
LIKELY FOLLOWED BY SOME LINGERING LIGHT PRECIP DOWNWIND OF LAKE
ERIE AND OVER THE WESTERN ALLEGHENIES/LAUREL HIGHLANDS TUE NIGHT
INTO EARLY WEDNESDAY. THE LATEST DETERMINISTIC, ENSEMBLE, AND
MACHINE LEARNING MODELS SHOW A LARGER STORM SYSTEM IMPACTING THE
REGION IN THE THURSDAY/FRIDAY TIMEFRAME WITH THE POTENTIAL FOR
RAIN AND SNOW. WE HAVE ABOVE AVERAGE CONFIDENCE IN MEASURABLE
PRECIP IN THIS TIME WINDOW (STICKING WITH NBM MAX POP 65-80%),
BUT DETAILS CONCERNING WINTER WX/PTYPE/ACCUMULATION ARE STILL
NOT CLEAR AT THIS RANGE. SOME LOCATIONS IN THE LOWER SUSQUEHANNA
VALLEY COULD REACH THE 50F MARK FOR 4 CONSECUTIVE DAYS MON-THU.
AVIATION /19Z THURSDAY THROUGH TUESDAY/
DIPS INTO LIFR ARE STILL OCCURRING, BUT ARE VERY BRIEF AND
SHOULD CONTINUE TO BE THAT WAY THANKS TO THE TINY SIZE OF THE
CELLULAR SHSN TOT HE S & W OF IPT AT 20Z. THIS SHOULD CONTINUE
TO BE THE CASE UNTIL A LITTLE AFTER SUNDOWN WITH BETTER
STRATIFICATION. 2SM+ VISBYS ARE NOT GOING TO BE COMMON
ELSEWHERE, ESP AFTER 02Z. THE BETTER VERTICAL ALIGNMENT TO THE
WINDS LATER THIS AFTN AND EVENING COULD LEAD TO A MORE BANDED
STRUCTURE TO THE SHSN. IF SO, THESE SHSN COULD EXTEND DOWN TO
LNS, WHERE VISBY SHOULD NOT GET DOWN TO IFR. AGAIN, MAINLY
BECAUSE OF THE DRY AIR UNDER THE CLOUDS.
UPSLOPE AND LAKE ENHANCED SNOW SHOWERS WILL CONTINUE FOR THE
LAUREL HIGHLANDS AND NW MTNS (KJST AND KBFD), WITH MVFR TO IFR
CIGS HOLDING ON THERE INTO AT LEAST FRIDAY MORNING. BFD WILL BE
THE LAST PLACE TO GO VFR ON FRIDAY WITH THE STRATOCU HANGING ON
LONGEST OVER NRN PA. THE WIND WILL BEGIN TO DIMINISH FRIDAY
AS WE GET CLOSER TO SUNSET, BUT SOME G20KT LINGER FRI EVENING.
HIGH PRESSURE THEN VISITS WITH ALMOST EXCLUSIVELY VFR CONDITIONS
FOR THE NEXT COUPLE OF DAYS.
OUTLOOK...
FRI NIGHT-SUN...VFR/NO SIG WX.
MON...RAIN AND SNOW SHOWERS DEVELOPING IN THE AFTERNOON NW.
CTP WATCHES/WARNINGS/ADVISORIES
WINTER WEATHER ADVISORY UNTIL 7 AM EST FRIDAY FOR PAZ033.
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...DANGELO
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page