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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 080333
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1133 PM EDT MON JUL 7 2014

.SYNOPSIS...
A VERY WEAK COLD FRONT WILL SLIDE SOUTHEAST ACROSS THE REGION
TONIGHT...BEFORE RETREATING BACK TO THE NORTH AS A WARM FRONT
EARLY TUESDAY. ANOTHER COLD FRONT WILL PUSH SOUTHEAST ACROSS
PENNSYLVANIA TUESDAY NIGHT AND EARLY WEDNESDAY. THESE WEATHER
FEATURES WILL SPARK A FEW ROUNDS OF SHOWERS AND THUNDERSTORMS THIS
EVENING THROUGH TUESDAY EVENING. A POOL OF MUCH COOLER AIR ALOFT
WILL BRING SOME AFTERNOON SHOWERS TO MAINLY THE NORTHERN MOUNTAINS
WEDNESDAY. HIGH PRESSURE BUILDING OVER THE COMMONWEALTH THURSDAY
AND FRIDAY WILL BRING CLEARING AND DRY CONDITIONS.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE REMAINDER OF SEVERE THUNDERSTORM WATCH NO 397 HAS BEEN
CANCELLED ABOUT AN HOUR EARLY ACROSS THE CENTRAL PORTION OF OUR
CWA.

DIFFUSE FRONTAL BOUNDARY WILL STRING OUT OVERNIGHT ACROSS CENTRAL
AND SOUTHERN PENN WITH LINGERING ISOLATED TO SCATTERED SHRA...AND
SOME AREAS OF LATE NIGHT FOG WHERE RAIN OCCURRED MONDAY EVENING.

PLENTY OF CLOUDS AND RELATIVELY HIGH SFC DEWPOINTS MAINLY IN THE
MID 60S WILL LEAD TO ANOTHER QUITE MILD NIGHT. LOW TEMPS WILL
RANGE FORM THE MID 60S ACROSS THE MTNS...TO AROUND 70F ACROSS THE
LOWER SUSQ VALLEY.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
THE AFOREMENTIONED...ILL-DEFINED FRONTAL BOUNDARY WILL MIGRATE
BACK TO THE NORTH TUESDAY MORNING AS THE MEAN LLVL FLOW BACKS BY
ABOUT 30 DEG /TO THE SW/.

MUCH BETTER SHEAR AND MOISTURE PUSHING EAST INTO THE REGION FOR
THE AFTERNOON AND EVENING. DEEP LAYER PW WILL BE APPROACHING 2"
AND THE 850 MB LLJ WILL RAMP UP TO >40 KTS ACROSS THE LAUREL
HIGHLANDS DURING LATE AFTERNOON AND EVENING. WARM AND MUGGY
CONDITIONS WILL PREVAIL FOR ANOTHER DAY...WITH HIGHS RANGING FROM
UPPER 70S NORTH TO UPPER 80S SOUTHEAST.

AS A MORE POTENT UPPER AIR DISTURBANCE AND SFC CFRONT PUSHES EAST
OUT OF THE OHIO VALLEY...EXPECT ANOTHER ROUND OR TWO OF SHOWERS
AND TSRA WITH GUSTY WINDS AND BRIEF TORRENTIAL RAINFALL RATES.

PRACTICALLY ALL OF THE CWA /WITH THE EXCEPTION OF SERN YORK AND
SERN LANCASTER COUNTY/ IS IN SPC/S DAY 2 SLIGHT RISK AREA. MODELS
INDICATE THE POTENTIAL FOR A COMPACT SFC WAVE TO DEVELOP INVOF
KERI/KBFD IN THE 21Z TUE-00Z WED WINDOW /BENEATH THE LEFT EXIT
REGION OF A 90 KT UPPER JET/. THIS FEATURE ALONG WITH THE
CORRESPONDING BELT OF ANOMALOUSLY STRONG /PLUS 3-4 ST DEVIATION/
45-55KT SWRLY 850 MB WINDS /AND AXIS OF NEARLY OFF-THE-CHARTS...
5-6 ST DEVIATION 850 MB MOISTURE FLUX/ WILL FOCUS/ENHANCE THE
SEVERE WEATHER /AND TORNADO/ POTENTIAL ACROSS THE NRN MTNS MID-
LATE TUESDAY AFTERNOON...THEN CENTRAL MTNS AND SUSQ VALLEY EARLY
TUESDAY EVENING. STORMS THAT CAN STRENGTHEN INTO POCKETS OF 0-1KM
EHI IN THE 2-3 M2/S2 RANGE COULD CONTAIN SOME LONG-LASTING MESOS
AND A FEW TORNADOES.

THE PRIMARY SEVERE WEATHER THREAT ACROSS THE SOUTHERN THIRD OF
THE CWA /GIVEN THE INCREASING AND STRONG UNIDIRECTIONAL FLOW FROM
THE SW/ SHOULD BE BOWING LINE SEGMENTS AND MICROBURSTS. BRIEF QLCS
TORNADOES COULD ACCOMPANY BKN-S SIGNATURES IN THE LINES.

WOULD NOT BE SURPRISED TO SEE SPC UPGRADE TO A MDT RISK FOR A
PORTION OF OUR CWA WITH LATER...DAY 1 CONVECTIVE OUTLOOKS ON
TUESDAY.

MAX TEMPS WILL BE IN THE U70S TO LOWER 80S ACROSS THE NORTH...AND
85-90F IN THE CENTRAL AND SOUTHERN VALLEYS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
NOT MANY BIG CHANGES TO PREVIOUS EXTENDED FORECAST. TSTM CHANCES
CONTINUE INTO TUE NIGHT/EARLY WED AS COLD FRONTAL BOUNDARY SLOWLY
CROSSES PA...FOLLOWED LATER IN THE DAY BY SECONDARY FRONT THAT
WILL PUSH HIGH PWAT AIR FURTHER TO THE SE. DID HOLD MENTION OF
LOW POPS IN SE INTO THU...THOUGH ACTIVITY MAY BE FURTHER SE.

HIGH PRESSURE TAKES OVER FOR LATE WEEK...WITH MOISTURE CREEPING
BACK IN FROM THE SOUTH OVER THE WEEKEND BRINGING INCREASING POPS
SAT INTO SUNDAY AS MID LEVEL LAPSE RATES GRADUALLY INCREASE.
BROAD TROUGH REMAINS OVERHEAD INTO EARLY NEXT WEEK...WITH MODELS
DIFFERING ON STRENGTH...SO LOW DAILY POPS WILL CONTINUE.

TEMPERATURES START OFF ABOVE NORMAL WITH NOTICEABLE HUMIDITY /ESP
SE/...BUT GRADUALLY COOL BACK TO SEASONAL NORMS BY LATE
WEEK...FOLLOWED BY ANOTHER WARMUP NEXT WEEK.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
SHOWERS HAVE LARGELY DISSIPATED LATE THIS EVENING...AS ATMOS
COOLS/STABILIZES. FORECAST CONCERN NOW SHIFTS TOWARD THE POSSIBILITY
LOW CIGS DEVELOPING OVR THE NW MTNS LATE TONIGHT. LATEST MDL DATA
SUGGESTS A PLUME OF MOISTURE AHEAD OF DYING COLD FRONT OVR THE E
GRT LKS WILL ASCEND THE HIGH TERRAIN OF NW PA...POSSIBLY RESULTING IN
LOW CIGS AT KBFD LATE TONIGHT.

A MORE SIGNIFICANT COLD FRONT WILL APPROACH CENTRAL PA LATE
TUESDAY. THIS FRONT WILL BRING ANOTHER ROUND OF TSRA TO CENTRAL PA
LATE IN THE DAY. DESPITE WIDESPREAD VFR CONDS...A BRIEF VIS
REDUCTION AND STRONG WGUST IS POSSIBLE FROM THESE STORMS LATE IN
THE DAY AND EVENING.

OUTLOOK...
WED...AM LOW CIGS/FOG POSS W MTNS. SLIGHT CHC OF PM TSRA IMPACTS SE.
THU-SAT...NO SIG WX EXPECTED.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...RXR
AVIATION...FITZGERALD