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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 300503
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
103 AM EDT WED JUL 30 2014

.SYNOPSIS...
BELOW NORMAL TEMPERATURES WILL CONTINUE TO GRIP THE REGION INTO
EARLY AUGUST BENEATH A BROAD AND ANOMALOUS UPPER LEVEL TROUGH
OVER THE EASTERN U.S.. THE OPPORTUNITY FOR APPRECIABLE RAINFALL
SHOULD PEAK DURING THE WEEKEND BEFORE DRYING OUT INTO EARLY NEXT
WEEK.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
SHOWERS AND STORMS PERCOLATING OVER THE RELATIVELY STEAMY WATERS
OF LAKE ERIE AT THIS HOUR AND INCHING TOWARD THE FAR NW. ALL IS
COVERED BY THE GOING FCST. THE 45F AT KBFD IS ALREADY COLDER THAN
LAST NIGHT...BUT CLOUDS ARE VARIABLE THERE AND MORE ARE MOVING
BACK TOWARD THEM FROM THE LAKE-INDUCED CONVECTION.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM THURSDAY/...
POTENT SHORTWAVE ROTATING S OF NEARLY STNRY UPPER LOW OVER JAMES
BAY INTO THE ERN GRT LKS REGION WILL TEAM WITH DAYTIME HEATING TO
LEAD TO WEAK INSTABILITY WITH ABNORMALLY COOL CYC FLOW ALOFT.
STEEP MID-LVL LAPSE RATES WILL SPREAD INTO CENTRAL PA DURING THE
LATE MORNING AND AFTN BENEATH POOL OF -15 TO -16C AIR AT 500MB.
EXPECT SCT CONVECTION TO DEVELOP WITH SOME STORMS CONTAINING SMALL
HAIL AND HAVE CONTINUED MENTION IN NDFD FCST AND ZONE TEXT.
SUPPOSE A FEW STRONGER CORES COULD HAVE HAIL APPROACHING SVR
LIMITS /1 INCH DIAMETER/ BEFORE GRADUALLY DIMINISHING INTO WED
NGT WITH THE LOSS OF HEATING. SPC D2 STILL HIGHLIGHTS THE NW MTNS
WITH A SEE TEXT. D2 MAX/MINS SHOULD WARM A FEW DEGREES BUT REMAIN
BELOW LATE JULY CLIMATE NORMALS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A DEEP UPPER LEVEL TROUGH WILL BE PRESENT ACROSS SOUTHEASTERN
CANADA EARLY IN THE LONG TERM PERIOD...BUT WILL RELOAD WITH A
SIGNIFICANT CHUNK ENERGY DIGGING INTO IT/S SW FLANK ACROSS THE MID
MISS AND OHIO RIVER VALLEYS LATE THIS WEEK AND OVER THE UPCOMING
WEEKEND /AS THE CANADIAN PORTION SHEARS OUT TO THE NE/.

THIS POTENT SHORTWAVE TROUGH /AND AN ASSOCIATED WELL-DEFINED RIGHT
ENTRANCE REGION OF A 90-95 KT 300 MB JET/ WILL LIFT NORTHEAST
ACROSS THE MID ATLANTIC REGION FRIDAY THROUGH SUNDAY BEFORE
SHIFTING TO THE SOUTHERN NEW ENGLAND COAST BY THE START OF NEXT
WEEK. A SLOW MOVING /AND LIKELY STRENGTHENING/ BAROCLINIC ZONE...
AND ONE OR MORE WAVES OF WEAK LOW PRESSURE MVG NE ALONG IT WILL BE
LOCATED ACROSS CENTRAL OR ERN PENN DURING THIS 2-3 DAY PERIOD.

WHAT THIS MEANS FOR OUR SENSIBLE WEATHER IS FOR A MAINLY
DRY THURSDAY INTO FRIDAY WITH SLIGHTLY BELOW NORMAL TEMPS. A FEW
WEAK IMPULSES ALOFT WILL RIDE EAST IN THE TEMPORARY ZONAL FLOW AND
BRING THE LOW PROBABILITY OF AN AFTERNOON SHOWER OR BRIEF...
LOW-TOPPED TSRA BOTH DAYS.

PERIODS OF UNSETTLED WEATHER /SHOWERS AND TSTMS/ WILL OCCUR LATER
FRIDAY...SATURDAY AND SUNDAY. THE STRENGTH OF THE LARGE SCALE
FORCING AND INCREASINGLY ANOMALOUSLY HIGH PWAT AIR BENEATH THE
NORTHWARD MIGRATING JET AND ITS THERMALLY DIRECT BRANCH WILL BRING
THE POTENTIAL FOR SOME LOCALLY HEAVY/TRAINING SHOWERS AND TSRA...
ESP ACROSS THE EASTERN HALF OF THE STATE/.

MODEL DETAILS DIFFER SLIGHTLY WITH RESPECT TO THE TIMING AND
LOCATION OF THE STRONGEST MESO/LARGER SCALE FORCING...BUT ALL
GUIDANCE AGREES ON THE BASIC EVOLUTION AND NE MOVEMENT OF THIS
TROUGH /AND AXIS OF HIGH...40-50MM PWAT AIR/ RIDING NWD UP ALONG
THE MID ATLANTIC PIEDMONT...AND SPREADING ACROSS THE EASTERN HALF
OF OUR CWA.

AS A RESULT OF THESE TIMING/LOCATION DIFFERENCES...POPS WERE
CAPPED OFF IN THE HIGH CHC CATEGORY...BUT AS THE FINER DETAILS
UNFOLD WITH HIGHER RES MODEL GUIDANCE OVER THE NEXT FEW
DAYS...POPS WILL UNDOUBTEDLY TREND HIGHER FOR SEVERAL PERIODS
BETWEEN LATE FRIDAY AND SUNDAY.

GRADUAL IMPROVEMENT /WITH NEAR NORMAL TEMPS/ IS EXPECTED FOR
EARLY NEXT WEEK.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
SKIES CLEARING ACROSS THE AREA JUST IN TIME FOR A RETURN OF MID
LEVEL CLOUD AHEAD OF AN APPROACHING UPPER DISTURBANCE CROSSING THE
LAKES.

THS SYSTEM...ALONG WITH WEAK INSTABILITY SHOULD PROMOTE ISOL SHRA
AND LOW-TOPPED TSTM DEVELOPMENT FROM LATE WED MORNING INTO THE
AFTN..WITH SOME OF THE STRONGEST STORMS CONTAINING SMALL TO
MARGINALLY SVR HAIL. WITH ISOLATED NATURE OF THIS
CONVECTION...KEPT RECENT AS VCSH AT THIS TIME.

OUTLOOK...
WED...SCT PM TSRA IMPACTS POSSIBLE.
THU...AM FOG POSSIBLE NW MTNS.
FRI-SAT...SCT PM TSRA IMPACTS POSSIBLE.

&&

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

&&

$$
SYNOPSIS...LA CORTE
NEAR TERM...DANGELO
SHORT TERM...STEINBUGL
LONG TERM...LAMBERT/STEINBUGL
AVIATION...STEINBUGL/TYBURSKI