Area Forecast Discussion
Issued by NWS State College, PA

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FXUS61 KCTP 231558
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1158 AM EDT SAT AUG 23 2014

.SYNOPSIS...
A MOIST LOW LEVEL EASTERLY FLOW WILL CREATE PLENTY OF CLOUDS...
COOL TEMPERATURES...AND PERIODS OF RAIN AND DRIZZLE FOR MUCH OF
THE REGION TODAY INTO TONIGHT. UPPER RIDGING WILL SLOWLY BUILD
OVER THE REGION BY SUNDAY...BRINGING AN END TO THE RECENT SIEGE OF
SHOWER AND THUNDERSTORM ACTIVITY. THE UPPER RIDGE WILL DOMINATE
THE WEATHER PATTERN OVER THE NORTHEAST UNITED STATES AND
SOUTHEASTERN CANADA DURING THE EARLY AND MIDDLE PART OF THE
UPCOMING WEEK...WITH THE NEXT CHANCE OF RAINFALL NOT ARRIVING
UNTIL LATE WEDNESDAY OR THURSDAY FROM AN APPROACHING MIDWESTERN
FRONTAL SYSTEM.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE COMBINED EFFECTS OF A PERSISTENT LOW LEVEL CONVERGENCE ZONE
ASSOCIATED WITH A NEARLY STATIONARY INVERTED TROUGH AND UPSLOPE
EAST-SOUTHEAST FLOW CONTINUE TO SUPPORT AN AREA OF LOW TOPPED
CONVECTION FROM SOUTHERN CLEARFIELD COUNTY DOWN TO THE MASON DIXON
LINE. SOME LOCALLY HEAVY RAIN IS BEING OBSERVED AND WE HAVE
ISSUED A COUPLE OF FLOOD ADVISORIES FOR MINOR FLOODING.

THE LARGE SCALE PATTERN IS ADVERTISED TO CHANGE ONLY SLOWLY OVER
THE NEXT 12-24 HOURS...WITH DRIER AIR EVENTUALLY SLIDING DOWN OUT
OF THE NORTH AND SHOVING THE HIGHER MOISTURE BACK TO OUR SOUTH AND
WEST.

FOR THE REMAINDER OF TODAY WE WILL TEND TO STAY UNSETTLED WITH
SOME OF THE SHOWERS BEING RATHER EFFICIENT IN PRODUCING HEAVY
RAIN. THE BIGGEST AREA OF CONCERN AS OF MID MORNING IS NEAR AND
AROUND COUDERSPORT WHERE THE SHOWERS HAVE BEEN NEARLY STATIONARY
FOR OVER AN HOUR. CALLS TO THE LOCAL OFFICIALS INDICATE NO
FLOODING PROBLEMS...YET.

THE PERSISTENT...AND ANOMALOUS SFC-850 MB EAST TO SERLY FLOW AND
APPROX 1.5 INCH PWAT AIR WILL MAINTAIN WIDESPREAD/THICK CLOUD
COVER AND UNSEASONABLY COOL TEMPS.

FAR NORTHWEST SECTIONS...AWAY FROM THE MARITIME FLOW...MAY WARM
INTO THE 70S. THE RESULTING INSTABILITY COULD POTENTIALLY RESULT
IN A PM THUNDER SHOWER.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
MOSTLY CLOUDY TO OVERCAST SKIES WILL PERSIST FOR MUCH /OR PERHAPS
ALL OF THE OVERNIGHT/ WITH A CHANCE OF LIGHT RAIN AND DRIZZLE
MAINLY BEFORE MIDNIGHT...AND ACROSS THE SE HALF OF THE CWA.

ANY CLEARING LATE TONIGHT WILL COMBINE WITH THE MOIST GROUND AND
LIGHT WIND TO PRODUCE AREAS OF FOG...THAT WILL BECOME LOCALLY
DENSE AFTER MIDNIGHT. LOW TEMPS EARLY SUNDAY WILL RANGE FROM THE
MID 50S ACROSS THE NORTH...TO AROUND 60F IN THE SOUTHERN VALLEYS.

A POCKET OF MUCH LOWER PWAT AIR BELOW ONE INCH WILL ADVECT SSW
INTO THE CWA DURING THE DAY SUNDAY ACCOMPANIED BY A SPRAWLING
1022 MB AREA OF SFC HIGH PRESSURE.

AREAS OF MORNING CLOUDS AND PERHAPS SOME PATCHY LIGHT DRIZZLE...
WILL TRANSITION INTO INCREASINGLY SUNNY SKIES DURING THE MIDDAY
AND AFTERNOON HOURS SUNDAY. TEMPS SUNDAY WILL REBOUND NICELY FROM
SATURDAY/S CHILL WITH AFTERNOON HIGHS IN THE MID 70S ACROSS THE
MTNS...AND AROUND 80F THROUGHOUT THE SUSQ VALLEY.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE EXTENDED WILL FEATURE A HIGH AMPLITUDE...588 DAM UPPER RIDGE
ACROSS THE MISS RIVER VALLEY SUNDAY...NOSING ACROSS THE GLAKES
REGION AND INTO SERN CANADA EARLY IN THE WEEK.

FAIR WEATHER WILL DEVELOP ALONG WITH WARMING TEMPERATURES AS THE
RIDGE ESTABLISHES ITSELF AND MAINTAINS ITS HOLD UNTIL AT LEAST
THURSDAY WHEN THE NEXT FRONTAL SYSTEM IS ADVERTISED TO
APPROACH...ALBEIT IN DIFFERENT FASHIONS BY THE VARIOUS MED RANGE
GUIDANCE PACKAGES.

THE OPERATIONAL GFS AND ECMWF KEEP US DRY THROUGH AT LEAST LATER
WEDNESDAY WHILE THE GEFS IS MORE PESSIMISTIC BRINGING MEASURABLE
RAINS EAST QUICKER UNDER A FLATTER UPPER FLOW. THE GEFS UPPER
PATTERN MORE CLOSELY RESEMBLES THE OPERATIONAL ECMWF SHOWING A
WEAKER TROUGH HANGING BACK IN THE MID WEST AS HEIGHTS IN THE EAST
SLOWLY FALL WITH THE EAST COAST RIDGE FLATTENING OUT IN TIME.

THE DIFFERENCES ARE AT THE END OF THE FORECAST PERIOD THROWING
DOUBT ON THE FORECAST SO I OPTED FOR A RATHER BLAND CHANCE OF
SHOWERS STARTING WEDNESDAY NIGHT LASTING INTO THURSDAY NIGHT.

OVERALL THE LAST FULL WEEK OF AUGUST WILL BE A SUMMERY ONE FOR
THE FIRST DAYS OF SCHOOL IN MANY COMMUNITIES. TEMPS WILL BE NEAR
TO A BIT ABOVE NORMAL MONDAY...THEN WILL REMAIN ABOVE NORMAL AT
LEAST THROUGH THE END OF THE WEEK WHEN THE AIRMASS SITUATION
BECOMES A LITTLE LESS CERTAIN.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
MORNING LOW CLOUDS STILL IN PLACE BUT FOG HAS LIFTED. WILL STILL
HAVE AREAS OF REDUCED CIGS AND VSBY MAINLY NEAR SHOWER ACTIVITY. FOG
AND CEILING RESTRICTIONS WILL AGAIN OVERSPREAD THE AREA TONIGHT.

IN THE LONGER RUN...HIGH PRESSURE WILL SLOWLY BUILD INTO THE
NORTHEAST THROUGH THE WEEKEND AND INTO MID WEEK. FRONT APPROACHING
LATER WEDNESDAY AND THURSDAY MAY BRING THE NEXT ROUND OF
SHRA/TSRA.

OUTLOOK...
SUN...LOW CIGS AND FOG EARLY...THEN VFR
MON- WED...MORNING RESTRICTIONS FROM FOG POSSIBLE...OTHERWISE
VFR.

&&

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

&&

$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...LA CORTE/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LA CORTE/LAMBERT
AVIATION...JUNG/ROSS



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