Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 301134
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
734 AM EDT SAT MAY 30 2015

.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH TODAY AS A COLD
FRONT REMAINS WELL TO THE NORTHWEST OF THE COMMONWEALTH. THE SLOW-
MOVING COLD FRONT WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS
THIS AFTERNOON INTO SUNDAY. A WELL-DEFINED WAVE OF LOW PRESSURE
RIDING EAST ALONG THE FRONT FROM THE OHIO VALLEY WILL LIKELY BRING
ANOTHER ROUND OF NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS TO
MUCH OF THE STATE SUNDAY...ALONG WITH MUCH COOLER TEMPERATURES
ACROSS THE NORTHERN HALF OF PENNSYLVANIA. LINGERING SHOWERS ARE
POSSIBLE MONDAY MORNING...BUT GENERALLY DRY WEATHER...WITH
SEASONABLE TEMPERATURES AND COMFORTABLE HUMIDITY IS EXPECTED TO
MOVE INTO THE STATE DURING THE DAY MONDAY...AND CONTINUE FOR THE
REST OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TRANQUIL CONDITIONS WILL CONTINUE FOR MUCH OF THE REST OF THIS
MORNING AS WEAK RIDGING OCCUR AT THE SFC...AND SW FLOW ALOFT.

SKIES WILL BE PARTLY TO MOSTLY CLOUDY THROUGH 16Z WITH MAINLY
AREAS OF ALTO CU CLOUDS /BASED BETWEEN 10-12 KFT AGL/ DRIFTING NE
ACROSS THE STATE.

PWATS ARE QUITE HIGH /BETWEEN 1.5-1.0 INCHES/ AND REFLECTED BY
SFC DEWPOINTS IN THE LOW- MID 60S. LIGHT WIND AND MILD TEMPS /JUST
A FEW TO SVRL DEG F ABOVE THE CURRENT DEWPOINTS/ WILL KEEP
CONDITIONS ON THE MODERATELY MUGGY SIDE.

A STRAY BRIEF SHOWER CAN/T BE RULED OUT THROUGH THE MID MORNING
HOURS...BUT POPS WILL BE ESSENTIALLY ZERO THROUGH 12Z
TODAY...BEFORE INCREASING TO CHC AMTS FOR SHRA AND ISOLATED TSRA
EARLY THIS AFTERNOON.

ANOTHER SUMMERY DAY IS ON TAP TO KICK OFF THE WEEKEND. THERE WILL
BE A TENDENCY FOR MORE WIDESPREAD DIURNAL CONVECTION TO BOIL UP.
STILL...WITH A COLD FRONT WELL OFF TO OUR NORTHWEST /AND ACROSS
LAKE HURON AND LOWER MICHIGAN TODAY/ THERE WILL BE NO REAL FOCUS
MECHANISM...ASIDE FROM PERHAPS A LEE TROUGH JUST WEST OF THE SUSQ
VALLEY/ SO TIMING WILL TEND TO FAVOR THE AFTERNOON AND EVENING.

SPC PAINTED MUCH OF PENN IN A MARGINAL RISK FOR SVR LATE TODAY AND
THIS EVENING. IT WILL BE A FAIRLY WEAK SHEAR...BUT MODERATELY HIGH
CAPE ENVIRONMENT... SO AFTERNOON AND EVENING PULSE STORMS WILL BE
THE PRIMARY MODE...WITH A SIGNIFICANT/ORGANIZED TRIGGERING
MECHANISM LACKING.

ENS MEAN 8H TEMPS ARE SUPPORTIVE OF MAX TEMPS WELL INTO THE 80S
THROUGHOUT THE CENTRAL AND SE VALLEY...WHILE HIGH TEMPS STAY
CLOSER TO 80F OVER THE HIGHEST TERRAIN OF THE NORTH AND WEST .

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
SFC COLD FRONT SAGS INTO THE STATE FROM THE NW OVERNIGHT. NUMEROUS
SHOWERS AND A FEW EARLY NIGHTTIME TSRA WILL OCCUR TONIGHT...WHILE
CONVECTION WILL BE MORE IN THE SCATTERED VARIETY IN THE SOUTH.

LOW TEMPS EARLY SUNDAYS WILL BE IN THE LOWER TO MID 50S ...THE
LOWER 60S FROM KJST TO KUNV AND KIPT.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHEST POPS IN THE EXTENDED PERIOD CONTINUE TO BE ADVERTISED FOR
THE SUNDAY AFTERNOON TO EARLY MONDAY TIMEFRAME AS COLD FRONT
STALLS AND A WELL-DEFINED APPORX 1010 HPA TRACKS ENE ALONG IT.

THE WAVE IS PROGGED TO RIPPLE ALONG THE FRONT AND CROSS PENN
SUNDAY AFTERNOON /BENEATH THE RIGHT ENTRANCE REGION OF UPPER JET/.
PERSISTENT FORCING AND RICH MOISTURE FEED WITH PW IN THE 1.33" TO
1.8" RANGE BRING THE BEST CHANCE OF HEAVY RAINFALL THAT WE`VE
SEEN IN QUITE SOME TIME /TO CENTRAL PA/. STRONGER 0-1KM SW TO
SOUTHERLY WINDS AT 850 MB AND WINDS WITH A VEERING PROFILE WILL
COMBINE WITH QUITE LOW LCLS TO ENHANCE SPC/S MARGINAL SVR WEATHER
THREAT.

CERTAINLY...THIS SLOW MOVING SYSTEM HAS THE POTENTIAL TO PRODUCE
AT LEAST MINOR FLOODING WHICH IS A SIGNIFICANT STATEMENT GIVEN
THAT WE`RE STARTING OUT MUCH DRIER THAN USUAL TO BEGIN.

TO THE NORTH OF THE FRONT...GUIDANCE REMAINS CONSISTENT ON COOLING
THINGS DOWN ACROSS NORTH CENTRAL PA...WITH EVEN SOME SIGNIFICANT
DRYING POSSIBLE AS DEWPOINTS POTENTIALLY DROP INTO THE 40S. TOO
EARLY TO GET HUNG UP ON THE DETAILS AS THEY WILL CHANGE...BUT AS
PREVIOUSLY MENTIONED...A COUPLE DAYS OF CLOUDY...COOL AND SHOWERY
WX APPEARS ON TAP FOR CENTRAL PA WITH THE STALLED FRONT AND
FREQUENT SHOWERS AND CHC OF THUNDERSTORMS.

A SLOW DRYING TREND BEGINS BY TUESDAY AS RICH PW PLUME SHIFTS
OFFSHORE AND SEVERAL DAYS OF COMFORTABLE TEMPERATURE AND HUMIDITY
LEVELS AND LOWER POPS APPEAR TO BE IN THE OFFING.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LOW MVFR CIGS BTWN 1-1.5KFT AGL AT LNS/IPT/MDT SHOULD CLR BY 16Z
GIVING WAY TO VFR BY LATE MORNING INTO THE AFTN WITH ISOLD TO
WDLY SCT TSTMS EXPECTED TO DEVELOP. THE COSPA/HRRR SUGGEST THE
GREATEST CVRG OVER THE WESTERN AIRSPACE/ZOB SECTOR. A SFC COLD
FRONT WILL APPROACH THE AIRSPACE TODAY FROM THE GREAT LAKES AND
OHIO VALLEY AND SHOULD CROSS INTO FAR NW PA BY EARLY SUNDAY. A
FRONTAL WAVE OF LOW PRES DEVELOPING ALONG THE OH RVR SHOULD STALL
THE FRONT INVOF NRN PA ON SUNDAY WITH REDUCTIONS LKLY IN THE NRN
AIRSPACE. SOUTH-CENTRAL AREAS WILL LKLY SEE VARIABLE CONDS WITH
MORE WIDESPREAD PCPN/TSTMS.

OUTLOOK...

SUN-MON...MVFR/IFR WITH RAIN/TSTMS.

TUE-WED...NO SIG WX.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...ROSS/DEVOIR
AVIATION...STEINBUGL



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