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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 290834
AFDCTP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
434 AM EDT TUE JUL 29 2014

.SYNOPSIS...
AN UNSEASONABLY DEEP UPPER LEVEL LOW PRESSURE AREA OVER JAMES BAY
WILL DIRECT COOL AIR INTO THE EASTERN UNITED STATES THIS WEEK. IT
WILL REMAIN COOLER THAN NORMAL FOR MOST OF THE WEEK...WITH ONLY A
SLIGHT WARM UP TO NEAR NORMAL TOWARD THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
555 DAM UPPER LOW CIRCULATING OVER JAMES BAY IS PULLING COLD AIR
ACROSS THE LAKES. THE MOISTURE IS CLIMBING THE SLOPE INTO THE
NORTHWESTERN AND CENTRAL MOUNTAINS. THIS SOUNDS LIKE WHAT WE WOULD
NORMALLY TYPE IN MID-WINTER AND NOT IN THE DOG DAYS. THE
RESULTING SENSIBLE WEATHER WILL BE A PLEASANT IF NOT CHILLY
SUMMER/S DAY. HIGH TEMPERATURES WILL RUN ABOUT 5 TO 15 DEGREES
BELOW NORMAL TODAY WITH 8H TEMPS ONLY IN THE MID TO UPPER SINGLE
DIGITS. THE COLD AIR ALOFT WILL ALSO RESULT IN INSTABILITY SHOWERS
DEVELOPING IN THE DAYTIME...MAINLY THE PEAK HEATING TIME. THE
HIGHEST POPS IT IS WORTH IS ABOUT 30 DUE TO THE EXPECTEDLY SPARSE
COVERAGE OVER THE NORTHWEST UNDER THE COLDEST AIR. WILL JUST
MENTION A SLIGHT CHC OF T IN THE FAR NW AS WELL. THE REST OF THE
AREA WILL STAY DRY WITH DEWPOINTS INCHING DOWN INTO THE M/U40S
EVERYWHERE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
SOME MEASURE OF STABILIZATION SHOULD OCCUR IN THE EVENING AND
RESULT IN A QUIET NIGHT. THERE COULD STILL BE A STRAY SHOWER IN
THE PRE-MIDNIGHT HOURS. BUT A LULL IN THE UPPER FORCING SHOULD
DIMINISH ALL THE SHOWERS AND MANY OF THE CLOUDS OVERNIGHT. TEMPS
WILL BE CHILLY AGAIN WITH LOWS TONIGHT VERY SIMILAR TO CURRENT
READINGS.

AROUND SUNRISE ON WEDNESDAY MOST OF THE SHORT-TERM GUIDANCE
BRINGS THE NEXT WAVE OF FORCING ALONG IN THE UPPER FLOW FROM THE
WEST. WINDS IN THE LOW LEVELS DO BACK A LITTLE. HEIGHTS DO NOT
REALLY FALL ON WEDNESDAY...BUT THE VORT MAX IS VERY POTENT. THE
BEST OF THE FORCING STAYS TO THE NORTH OF THE LOWER LAKES. WILL
INTRODUCE A MENTION OF SMALL HAIL TO THE SCT/NMRS TSRA FOR THE NW
ON WED AS SPC HAS ALSO MENTIONED IN THE DY2 OUTLOOK. TEMPS WILL
STAY BELOW NORMAL BUT WE SHOULD ADD 3-4F ONTO WHAT WE SEE
TODAY/TUES. AGAIN...WITH THE LOSS OF DAYTIME HEATING...THE
SHOWERS/STORMS WILL DIMINISH AND PERHAPS QUICKLY/COMPLETELY BY 9
PM...AS THE FORCING WILL MOVE TO THE EAST AND THE FOLLOWING
SUPPRESSIVE FORCING/SINKING WILL QUELL THE INSTABILITY.
MEANWHILE...THE 8H TEMPS WILL HAVE WARMED A LITTLE AND WILL BE UP
TO A BALMY 10C FOR THE NIGHT. DEWPOINTS WILL HAVE RISEN SLIGHTLY
AND THURS MORNING LOWS WILL BE IN THE 50S AREAWIDE.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
THE DEEP TROUGH WILL LINGER THROUGH THE WEEK WITH INDIVIDUAL
IMPULSES MOVING THROUGH THE GREAT LAKES. DAYTIME HEATING AND
INSTABILITY WILL BE THE FAVORED TIMES FOR SHOWERS THROUGH
THURSDAY.

THEN THE MODELS SHOW GOOD AGREEMENT IN RETROGRADING THE UPPER
TROUGH...IN THE FRIDAY THROUGH SUNDAY TIMEFRAME. THIS ALLOWS FOR A
SLIGHT REBOUND IN THE WESTERN ATLANTIC RIDGE AND FOR AN INCREASE
IN MOISTURE MOVING UP THE EASTERN SEABOARD. IT WILL ALSO ALLOW FOR
A MODERATION IN TEMPERATURES WITH HUMIDITY RETURNING TO SOMETHING
MORE RECOGNIZABLE FOR THE HEIGHT OF SUMMER.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SHOWERS GONE NOW...BUT STILL SOME CLOUDS.

EXPECT LESS SHOWER ACTIVITY TODAY THAN ON MONDAY.

06Z TAFS SENT.

EARLIER DISCUSSION BELOW.

MAIN AVIATION CONCERN TONIGHT WILL BE THE POTENTIAL OF LOW CIGS
AT KBFD AND JST...THE RESULT OF LOW LVL MOISTURE ASCENDING THE
HIGH TERRAIN OF THE ALLEGHENY MTNS. ADVECTION OF DRIER AIR HAS
TEMPORARILY IMPROVED CONDS AT KBFD/KJST WITH BOTH LOCATIONS
REPORTING ONLY A SCT LAYER ARND 800FT AT 03Z. HOWEVER...MODEST
RADIATIONAL COOLING AND ASSOC MOISTENING OF BLYR MAY RESULT IN A
RETURN TO IFR CIGS LATER TONIGHT. LATEST MDL SOUNDINGS SUGGEST THE
BEST CHANCE OF LOW CIGS WILL OCCUR BTWN 09Z-12Z. FURTHER
EAST...DOWNSLOPING NW FLOW SHOULD YIELD BETTER FLYING CONDS IN THE
RIDGE/VALLEY REGION WITH OCNL MVFR LIKELY AT KAOO AND KUNV. THE
LOWER ELEVATION AIRFIELDS ACROSS THE SUSQ VALLEY SHOULD REMAIN VFR
OVERNIGHT.

ANY EARLY LOW CIGS SHOULD MIX OUT SHORTLY AFTER DAWN TUESDAY. FOR
THE REST OF THE DAY...THERE IS A HIGH CONFIDENCE OF VFR CONDS AND
LIGHT WIND...AS HIGH PRES AND ASSOC DRY AIR MASS BUILDS OVR THE
STATE. COLD AIR ALOFT WILL PRODUCE PLENTY OF AFTN CU WITH CIGS
ARND 5KFT.

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

&&

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

&&

$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...LA CORTE/STEINBUGL
AVIATION...FITZGERALD/MARTIN