-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBGM 180531
AFDBGM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
131 AM EDT TUE JUN 18 2013

.SYNOPSIS...
MAINLY QUIET TONIGHT...THOUGH A FEW SHOWERS WILL BE POSSIBLE IN
PARTS OF CENTRAL NEW YORK TOWARDS DAWN. ANOTHER ROUND OF SHOWERS
AND POSSIBLE THUNDER MAY OCCUR TUESDAY AS A WAVE OF LOW PRESSURE
MOVES ACROSS THE AREA...WITH BEST CHANCES FROM THE TWIN TIERS AND
CATSKILLS SOUTHWARD. HIGH PRESSURE WILL BRING DRY WARM WEATHER
WEDNESDAY AND THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
10 PM UPDATE...
SURFACE FRONT SWEPT THROUGH SEVERAL HOURS AGO WITH STRONG TO
MARGINALLY SEVERE THUNDERSTORMS...FOLLOWED BY ISOLATED SHOWERS AND
THUNDERSTORMS THAT POPPED UP ALONG THE LAKE BREEZE UPSTREAM /WHICH
MOVED INTO SOME OF THE FINGER LAKES/ AND PERHAPS AN OLD OUTFLOW
BOUNDARY FARTHER EAST. THAT ACTIVITY FELL APART WITH LOSS OF
DIURNAL HEATING.

HOWEVER...THERE CLUSTERS OF SMALL THUNDERSTORMS IN SOUTHERN
MICHIGAN AND NOW LAKE ERIE...ASSOCIATED WITH A WEAK VORTICITY WAVE
EMBEDDED IN THE BRISK ZONAL FLOW. FORECAST WAS UPDATED EARLIER TO
ALLOW AT LEAST A LOW CHANCE OF SHOWERS TO ADVANCE INTO OUR
NORTHWESTERN ZONES BEFORE DAWN. LIFTED AND EVEN SHOWALTER INDICES
ARE POSITIVE BY THE TIME THIS HAPPENS...SO NOT EXPECTING THUNDER
WHEN THAT ARRIVES. EXCEPTION IS THAT I ALLOW SLIGHT CHANCE OF
THUNDER IN THE CENTRAL SOUTHERN TIER OF NY WHERE SHOWALTER INDICES
WILL BE MARGINALLY SUBZERO...AND THERE WILL BE SOME ELEVATED
INSTABILITY.

SKY GRIDS WERE ALSO INCREASED...WITH SHORTWAVE EXPECTED TO BRING
IN CLOUD COVER ACROSS MOST OF THE AREA. THIS SHOULD ALSO PREVENT
FOG FORMATION FROM OCCURRING FOR MOST VALLEYS.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
1030 PM UPDATE...
ADJUSTED GRIDS TO FOCUS THE BETTER THUNDER CHANCES ON THE SOUTHEAST
HALF OF THE AREA...ESPECIALLY NEPA...WHERE INSTABILITY WILL BE
GREATEST. REMAINDER OF GRIDS LARGELY UNCHANGED FROM AFTERNOON
UPDATE.

PREVIOUS DISCUSSION...
NEXT UPPER LEVEL WAVE WILL SWING EAST ACROSS THE AREA ON TUESDAY
AS UPPER LEVEL LOW PRESSURE DROPS SOUTHEAST ACROSS QUEBEC. SFC
RESPONSE WILL BE DEVELOPMENT OF A WEAK AREA OF LOW PRESSURE OVER
THE MID-ATLANTIC STATES ON TUESDAY. SCATTERED SHOWERS WILL DEVELOP
ACROSS THE AREA ON TUESDAY IN RESPONSE TO THIS FORCING.
INSTABILITY LOOKS TO BE QUITE SMALL... ONLY MARGINALLY LARGE ENOUGH
FOR THUNDER AND ANY THUNDERSTORMS SHOULD REMAIN BELOW SEVERE
LIMITS.

HIGH PRESSURE WILL BUILD ACROSS THE AREA ON WEDNESDAY AND TUESDAY
BRINGING DRY WEATHER. TEMPERATURES WILL REMAIN A FEW DEGREES BELOW
NORMAL ON WEDNESDAY WITH HIGHS MOSTLY 70 TO 75... INCREASING TO 75
TO 80.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BRIEF DISC DUE TO ONGOING SVR WX...SFC HIPRES IN CNTRL AT THE
START OF THE LONG TERM WITH DRY CONDITIONS UNDER A NW FLOW ALOFT.
SHRT WVS DROPPING INTO THE REGION MAY BRING SOME SHWRS AND STORMS
SAT NGT AND SUN. SLOWLY RISONG TEMPS IS XPCTD WITH ABV NRML OVER
THE WEEKEND AS THE RDG BLDS.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
CDFNT DROPPING SWD ACRS THE FCST AREA INTO NE PA BY LATE
MRNG/EARLY AFTN...WITH GREATEST POTNL FOR CONVECTION NEAR THIS BNDRY
ACRS NE PA LATER THIS AFTN. OTRW...GNRLY SCT-BKN MID CLDS EARLY
THIS MRNG WITH SCT --SHRA MAINLY NRN SXNS. TWDS DAYBREAK AND
BEHIND THE CDFNT...MDLS/PROFILES ARE ADVERTISING POTNL FOR A BAND
OF MVFR CIGS DROPPING SWD INTO CNTRL NY. XPCT BEST POTNL AT
SYR/RME AND ITH 12-17Z. ALSO POTNL FOR BRIEF MVFR AT AVP THIS AFTN
IN TSRA. TNGT...XPCT MAINLY VFR...BUT POTNL FOR SOME LOW CLDS TO
PERSIST AT AVP. WINDS L&V EARLY THIS MRNG....BECMG NRLY TO NE
10-15 KTS BEHIND THE FNT.

OUTLOOK...
TUE NGT THRU SAT...PRIMARILY VFR.
-- End Changed Discussion --

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.

&&

$$
SYNOPSIS...MDP
NEAR TERM...MDP
SHORT TERM...MSE
LONG TERM...DGM