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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 311257
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
857 AM EDT THU JUL 31 2014

.SYNOPSIS...
A CLOSED UPPER LEVEL LOW PRESSURE CENTERED OVER JAMES BAY WILL
LIFT SLOWLY NORTHEAST TODAY. HOWEVER...THE ASSOCIATED LONG WAVE
TROUGH WILL SHARPEN UP OFF TO OUR WEST THROUGH THE WEEKEND.
THUS...INCREASINGLY HUMID AND UNSETTLED CONDITIONS ARE EXPECTED
FOR THE WEEKEND. TEMPERATURES WILL REMAIN COOLER THAN NORMAL.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE PATCHY DENSE FOG HAS STEADILY DISSIPATED OVER THE PAST HOUR
WITH MOST LOCATIONS A0A 2SM IN VSBY.

MOST PLACES WILL SEE A QUITE MORNING WITH CLOUDS ACROSS THE
NORTHWEST AND A FEW SHOWERS DRITING ACROSS THE SW MTNS.

BEST HEATING AND QUICKEST INCREASE IN INSTAB WILL OCCUR ACROSS THE
SE ZONES THROUGH THE MIDDAY...WHERE SKIES WILL BE MSTLY SUNNY
PRIOR TO THE APPROACH OF SOME ENHANCED MESOSCALE /ASSOCIATED WITH
THE RIGHT ENTRANCE REGION OF A 70 KT JETLET/.

PREVIOUS DISC...
WORKING OFF THE PREMISE OF A MORE COMPACT AREA OF FORCING AND NOT
TWO SEPARATE VORT MAXIMA...THERE SHOULD BE A QUICKER EXIT TO THE
MAIN BUNCH OF SHOWERS ACROSS THE NORTH TODAY. THE BEST FORCING
WILL BE DURING THE MORNING...BUT THE BEST INSTABILITY WILL BE IN
THE MID-DAY HOURS. SO THERE MIGHT BE CONVECTION FORM AS THE TAIL
END OF THE FORCING PRESSES THROUGH THE CWA. HIGHEST POPS WILL BE
IN THE MORNING ACROSS THE NORTH. BUT LOW CHC POPS STILL A GOOD
IDEA FOR MUCH OF DAY...INCHING OFF TO THE EAST BY SUNSET. GOOD
SUNSHINE THIS MORNING OVER MUCH OF THE AREA WILL HELP TEMPS GET A
FEW DEGS WARMER THAN WED - VERY NEAR NORMAL IN THE SRN TIER BUT
STILL 5-10F BELOW NORMAL IN THE REST OF THE AREA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
NAM AND GFS BOTH HINT AT A MINOR CHC OF A SHOWER IN THE NRN TIER
IN THE EVENING. WILL JUST LEAVE A 20 POP THERE FOR THE TIME BEING
WHILE DROPPING POPS OFF IN THE EAST. WINDS OVER THE OHIO VALLEY
REMAIN SRLY AT THE SFC AND THE UPPER LOW ROTATES UP TO THE
NORTHEAST - ALLOWING HEIGHTS TO REBOUND. BUT THE YIN OF RISING
HEIGHTS WILL BE ACCOMPANIED BY A YANG OF A DIP IN THE LONG WAVE
TROUGH. THE AXIS OF THIS TROUGH WILL REMAIN TO OUR WEST INTO THE
NEXT WEEK. CONTINUED UNSETTLED CONDITIONS ARE IN STORE AS PWATS
RISE ON GOOD POLEWARD FLOW AND AN INVERTED SFC TROUGH FORMS ALONG
THE EAST COAST. THE NORTHWARD SURGE OF MOISTURE WILL LIKELY
TRIGGER SHOWERS AND THUNDERSTORMS OVER THE MID-ATLANTIC TONIGHT
WHICH WILL RISE INTO THE AREA FOR FRIDAY AND INTO THE LONG TERM
PERIOD. TEMPS DO GET NEARER TO NORMAL ON FRIDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
THE GLOBAL MODELS AND ENSEMBLE MEMBERS SHOW THE HIGHLY AMPLIFIED
NOAM WESTERN RIDGE/EASTERN TROUGH CONFIGURATION RELAXING INTO
EARLY NEXT WEEK...BUT OTHERWISE MAINTAINING ITS ORIENTATION. THE
RISING 500MB HGTS SHOULD ALLOW TEMPERATURES TO EDGE BACK TOWARD
EARLY AUGUST CLIMATE NORMALS. THE GENERAL PATTERN REMAINS UNSETTLED
THROUGH THE WEEKEND.

THE MEAN UPPER TROUGH AXIS SHIFTS WWD TO NEAR 90W WHICH SHOULD
ALLOW THE QSTNRY FRONTAL ZONE DRAPED ALONG THE EASTERN SEABOARD
TO DRIFT WWD ALONG THE I-95 CORRIDOR. THE 12Z/30TH GEFS SHOWS
PLUME OF HI PWATS POOLING NEAR THE SFC BOUNDARY ALONG/E OF THE
APPLCHN SPINE. THIS SUGGESTS THE POTENTIAL FOR HVY RAFL SETTING UP
FROM THE SRN MID ATLC STATES UP INTO SERN PA/DELMARVA/NJ AREAS.
THERE ARE STILL SOME QPF DIFFERENCES BUT THE LATEST RUNS SEEM TO
BE CONVERGING TOWARD THE IDEA THE THE MAIN QPF AXIS WILL BE EAST
OF THE APPLCHNS...ALTHOUGH THE DIURNAL CYCLE AND INDIVIDUAL
SHORTWAVES MOVING THROUGH THE LW TROUGH WILL PLAY A ROLE IN THE
DURATION AND PLACEMENT.

CONDITIONS SHOULD IMPROVE INTO EARLY NEXT WEEK AS THE HI PWAT
PLUME SHIFTS S/E AND DRIER AIR ARRIVES ACCOMPANIED BY SFC HIGH
PRES ON MON. NRN STREAM ENERGY IS SLATED TO PUSH A COLD FRONT SWD
INTO THE AREA BY NEXT TUE/WED WHICH MAY STALL OUT FROM THE OH VLY
INTO THE MID ATLC STATES.

&&

.AVIATION /13Z THURSDAY THROUGH MONDAY/...
A CLOSED UPPER LEVEL LOW PRESSURE CENTERED OVER JAMES BAY WILL
LIFT SLOWLY NORTHEAST TODAY.

WIDE RANGE OF CIG/VSBY CONDITIONS ACROSS CENTRAL PA EARLY THIS
MORNING WILL GRADUALLY IMPROVE BACK TO VFR BY MID MORNING. ANOTHER
WAVE SLIDES THROUGH TROUGH FIRST HALF OF TODAY...AND SHOULD KICK
OFF SCT SHOWERS MAINLY ACROSS NORTHERN MTNS. BETTER INSTABILITY
ARRIVES IN THE AFTERNOON...AND ISO CONVECTION CAN/T BE RULED OUT.
BUT OVERALL PROBS TOO LOW TO MENTION IN TERMINALS. THOUGH BEST
CHANCE FOR IMPACTS TODAY WILL BE NEAR KBFD. LIGHT WINDS PICK UP
TO AROUND 10 MPH FROM THE SW TODAY...BEFORE BECOMING LIGHT AGAIN
TONIGHT.

JUST AN OUTSIDE CHANCE FOR A SHOWER IN THE NORTH TONIGHT.
OTHERWISE GENERALLY QUIET WEATHER WITH SOME FOG DEVELOPING AGAIN
AFTER MIDNIGHT.

OUTLOOK...
FRI-SUN...SCT PM TSRA IMPACTS POSSIBLE.
MON...SLOW IMPROVEMENT EXPECTED WITH AREAS OF MVFR POSSIBLE
MAINLY IN THE MORNING.

&&

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

&&

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