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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 170547
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
147 AM EDT MON JUN 17 2013

.SYNOPSIS...
A WEAK COLD FRONT WILL SLIDE SLOWLY SOUTHEAST ACROSS CENTRAL
PENNSYLVANIA TONIGHT. HIGH PRESSURE WILL VISIT BRIEFLY ON MONDAY
WHILE THE FRONT STALLS JUST TO THE SOUTH OF THE REGION. ANOTHER WAVE
OF LOW PRESSURE WILL ROLL EAST THROUGH THE APPALACHIANS ON TUESDAY.
GENERALLY DRY WEATHER WILL FOLLOW FOR THE SECOND HALF OF THE WEEK AS
A LARGE AREA OF HIGH PRESSURE BUILDS INTO THE REGION FROM THE UPPER
MIDWEST. TEMPERATURES LOOK LIKE THEY COULD GET HOT NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
-- Changed Discussion --
RUC13 850 MB THETA E FIELD DEPICTS NEARLY STATIONARY FRONTAL
BOUNDARY SLOWLY SINKING SOUTHWARD OVERNIGHT. ISOLATED SHOWERS AND
THUNDERSTORMS CONTINUE TO FIRE IN THE WARM SECTOR AHEAD OF THE
BOUNDARY WITH BRIEF DOWNPOURS DROPPING UP TO 0.10" IN 5 MINUTES
(0.07" HERE AT THE OFFICE SINCE 130 AM).

BOUNDARY SHUD CONTINUE TO SINK SOUTHWARD OVERNIGHT...WITH ONGOING
CONVECTION BATTLING INCREASINGLY STABLE STRATIFICATION TO THE
SOUTH AND EAST. KEPT HIGHEST POPS ACROSS THE WEST CENTRAL AND
CENTRAL MOUNTAINS IN THE 05-08Z TIMEFRAME BEFORE SHOWERS FIZZLE.
ELSEWHERE...SKIES WILL BE PARTLY TO MOSTLY CLOUDY WITH LITTLE OR
NO CHANCE FOR RAIN...ALONG WITH LIGHT SOUTHWESTERLY WINDS.

CURRENT TEMPS ON TRACK TO REACH LOWS IN THE U50S TO NEAR 60F
ACROSS THE MTNS...AND LOWER TO MID 60S ELSEWHERE.
-- End Changed Discussion --

&&

.SHORT TERM /7 AM THIS MORNING THROUGH 6 PM TUESDAY/...
THE FRONT STALLS OFF TO OUR SOUTH DURING THE DAY...AND A WEAK
IMPULSE OR TWO RIDING IN FROM THE WEST COULD TOUCH OFF A FEW SHRA IN
THE SRN COS...ESP OVER THE LOWER SUSQ IN THE MORNING. ADDITIONAL
ENERGY ROLLING W-E OFF TO OUR NORTH ON TUESDAY COULD AGAIN HELP TO
MAKE ISOLD SHRA IN THE AFTN ON MONDAY. THE AFTN CAPES ON THE NAM
SEEM OVERDONE...AS DO THE NAM MOS MAX TEMPS IN THE U80S IN THE EAST.
WILL TEMPER THOSE BY A FEW DEGS - KEEPING THEM CLOSE TO THE GFS MOS.
THIS MAKES SENSE WITH 8H TEMPS IN THE MID-TEENS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
BROAD TROUGH OVER NORTHEAST U.S. WILL BRING AN UNSETTLED START TO
THE WEEK...BUT RIDGE BUILDING IN STARTING MIDWEEK WILL BRING DRY
AND COOLER WEATHER BEFORE MORE HUMID AND SHOWERY CONDITIONS RETURN
FOR THE WEEKEND.

FRONTAL BOUNDARY PUSHING SOUTH ACROSS CWA MONDAY WILL GET HUNG UP
NEAR THE MASON/DIXON LINE MONDAY NIGHT AS WINDS TURN WESTERLY
/PARALLEL TO FRONT/. SHORTWAVE RIDES IN OVERHEAD...CONTINUING
POPS ACROSS SOUTHERN PORTION OF CWA.

THIS FRONT WILL LIKELY MEANDER BACK NORTHWARD A BIT /INTO
SOUTHERN OR CENTRAL PENN/ FOR TUESDAY AS ANOTHER FAST MOVING
WAVE ALOFT SLIDE EAST ACROSS THE REGION...AND LAPSE RATES
SUPPORT A FEW ROUNDS OF SHOWERS AND THUNDERSTORMS DURING THE DAY.

NORTHERLY FLOW DEVELOPS TUE NIGHT INTO WED AS HIGH PRESSURE
BUILDS SOUTHWARD ACROSS GLAKES...WHICH WILL KICK THE FRONTAL
BOUNDARY FURTHER SOUTH AND USHER IN BEGINNING OF A PERIOD OF
DRIER AND COOLER WEATHER.

WE/LL SEE A FEW CHILLIER NIGHTS...ESP ACROSS THE NORTH /THE
COLDEST BEING WED NIGHT WITH READINGS DIPPING INTO THE 40S NORTH
OF I-80/ AS HIGH SETTLES IN. BUT SOUTHWESTERLY RETURN FLOW BEGINS
ON THU AS RIDGE AXIS DRIFTS TO OUR EAST. AS LOWER LEVELS BEGIN TO
SLOWLY MOISTEN BACK UP...ISOLATED LATE DAY TSTMS AGAIN BECOME
POSSIBLE OVER SOUTHERN HALF THU AND ESP FRI.

HEIGHTS RISE HEADING INTO THE WEEKEND. SURGE OF MOISTURE ALSO GETS
SHUNTED EASTWARD FROM THE CENTRAL U.S. BRINGING A NOTICEABLE
INCREASE IN THE HEAT AND ESPECIALLY HUMIDITY. TSTM PROBABILITIES
INCREASE SAT...PEAKING ON SUNDAY BEFORE A COLD FRONT DROPS ACROSS
THE GLAKES EARLY NEXT WEEK BRINGING A GRADUAL CHANGE IN AIRMASS
BACK TOWARD DRIER CONDITIONS.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
A NEARLY STATIONARY FRONTAL BOUNDARY LIES ALONG THE I-80 CORRIDOR
THIS EVENING...WHILE SOUTH OF THE FRONT A PLUME OF MOIST AIR IS
FLOWING ACROSS SOUTHERN PA ON A WESTERLY FLOW. CAN/T RULE OUT A
BRIEF SHRA/TSRA AT EITHER UNV OR IPT BTWN 04Z-06Z. HOWEVER...CONFIDENCE
NOT THAT HIGH ATTM BASED ON RADAR TRENDS.

THE BIGGEST AVIATION CONCERN WILL BE LATER TONIGHT ACROSS THE W
MTNS...WHERE THE PERSISTENT...MOIST WESTERLY FLOW ASCENDING THE
ALLEGHENY HIGHLANDS COULD RESULT IN SOME LOW CIGS...ESP AT JST. JST
REPORTING A 1300 FT CIG AT 03Z AND BULK OF LATEST MDL DATA SUPPORTS
IFR CIGS DEVELOPING LATE TONIGHT AT JST AS BLYR COOLS/MOISTENS.

THE SLOW MOVING FRONT WILL HAVE PASSED JUST SOUTH OF PA ON
MONDAY...KEEPING AN ISOLD SHRA POSSIBLE ACROSS THE FAR SRN TIER
MON MORNING. BUT...MUCH OF THE AREA WILL REMAIN DRY. WILL NOT
MENTION ANY PRECIP FOR ANY TERMINALS FOR 12-18Z MONDAY...BUT
MDT/LNS COULD PICK UP A SHOWER DURING THE EARLY MORNING HOURS. MDL
SOUNDINGS INDICATE ANY EARLY LOW CLOUDS ACROSS THE W MTNS WILL MIX
OUT TO MSUNNY SKIES BTWN 12Z-15Z.

OUTLOOK...
TUE...PATCHY FOG POSSIBLE EARLY AM. PM TSRA IMPACTS POSS SOUTH.
WED-FRI...NO SIG WX EXPECTED.

&&

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

&&

$$
SYNOPSIS...DANGELO/LAMBERT
NEAR TERM...DEVOIR/LAMBERT
SHORT TERM...DANGELO/LAMBERT
LONG TERM...RXR
AVIATION...FITZGERALD