-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBGM 232337
AFDBGM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
737 PM EDT THU MAY 23 2013

.SYNOPSIS...
A STRONG COLD FRONT WILL PUSH THROUGH THE REGION THIS EVENING
BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS TO THE REGION.
BEHIND THIS FRONT...MUCH COLDER AIR WILL FILTER INTO THE REGION AS
COLD CANADIAN AIR SETTLES SOUTHWARD. BY THE WEEKEND...EXPECT WELL
BELOW AVERAGE TEMPERATURES WITH POSSIBLE FROST DEVELOPMENT BOTH
SATURDAY AND SUNDAY MORNING.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
7 PM...PRE FNTL BNDRY NOW OVER THE CNTR OF THE FCST AREA WITH THE
COLD FNT MVG INTO THE FAR WEST. ADJUSTED GRIDS FOR TEMPS TRENDS
WITH THE INITIAL FALL BHD THE LINE OF CONV...BUT COLDEST AIR STILL
WELL BACK AND JUST ENTERING THE BUF CWA. OTRW MINOR ADJUSTMENTS TO
THE FCST ATTM. PRVS DISC BLO.

MAIN FOCUS REMAINS ON POTENTIAL SEVERE WX THIS AFTERNOON AS LONG
AWAITED COLD FRONT APPROACHES FROM THE WEST. THAT SAID...LATEST
SFC ANALYSIS NOW PLACES MAIN COLD FRONT ALONG A LINE FROM
PETERBOUROUGH...SOUTHWEST TO NEAR HAMILTON ONTARIO AND APPROACHING
THE NIAGARA FRONTIER REGION OF WESTERN NY. FURTHER TO THE EAST...A
PRE-FRONTAL TROUGH IS APPARENT ON VIS SATELLITE IMAGERY THIS
AFTERNOON WHICH RESIDES FROM NEAR SYR SOUTHWEST THROUGH THE
CENTRAL SOUTHERN TIER. SO FAR REGIONAL RADAR HAS SHOWN FAIRLY
DISORGANIZED ACTIVITY ACROSS MUCH OF WESTERN NY ALONG WITH
SCATTERED ACTIVITY FURTHER EAST ALONG THE PRE-FRONTAL TROUGH ACROSS
THE BGM CWA. IN ADDITION TO THE SEVERE THREAT...ATTENTION WILL
ALSO BE FOCUSED ON POSSIBLE HYDRO CONCERNS AS HEAVY RAINS IN
RECENT DAYS COMBINED WITH A STILL ABNORMALLY MOIST ATMOSPHERE MAY
RESULT IN LOCALIZED FLOOD CONCERNS ACROSS PORTIONS OF THE WESTERN
MOHAWK VALLEY AND WESTERN CATSKILLS. THAT SAID...WE CANNOT TOTALLY
RULE OUT THE POSSIBILITY OF NEEDING A SHORT-FUSED FLASH FLOOD
WATCH LATER THIS AFTERNOON AND EVENING...BUT INITIAL RADAR TRENDS
DEPICTING STEADY NORTHEASTWARD MOVEMENT ALONG WITH THE
DISORGANIZED APPEARANCE OF CONVECTION ON RADAR SUGGEST HOLDING OFF
MAY BE THE BEST COURSE OF ACTION.

NOW TO THE MEAT AND POTATOES OF SEVERE POTENTIAL...
DEEP UPPER POSITIVELY TILTED TROUGH CONTINUING TO DIG SOUTH ACROSS
THE CENTRAL GREAT LAKES THIS AFTERNOON WITH WARM CONVEYOR BELT
ADVECTING HIGH AMOUNTS OF MOISTURE NORTH INTO THE NORTHERN
MID-ATLANTIC. WITH WELL-ESTABLISHED SOUTHWEST FLOW
ALOFT...SEVERAL INDIVIDUAL SHORTWAVES CONTINUE RIDING NORTHEAST
ACROSS THE FCST REGION THIS AFTERNOON...WITH MAIN TROUGH PV
ANOMALY AND ASSOCIATED SHORTWAVE STILL DISPLACED WEST ACROSS
NORTHERN OHIO VALLEY. MEANWHILE...VISIBLE SATELLITE IMAGERY STILL
DEPICTING A FAIR AMOUNT OF LOW/MID-LEVEL STATUS WHICH HAS HAMPERED
THE DESTABILIZATION PROCESS TO SOME DEGREE...AS LATEST SPC MLCAPE
VALUES AVAILABLE FROM THE MESOANALYSIS PAGE ONLY SHOW ROUGHLY 500
JOULES ACROSS CENTRAL/WESTERN NY. THE ABOVE SAID...WE/RE STILL BY
NO MEANS OUT OF THE WOODS AS INCREASING MOISTURE CONVERGENCE ALONG
THE APPROACHING FRONT AND PRE-FRONTAL TROUGH COMBINED WITH BETTER
FORCING AS SHORTWAVE ENERGY FROM THE OHIO VALLEY ARRIVES WILL
LIKELY LEAD TO ADDITIONAL SHWR/STORM DEVELOPMENT THROUGH THE
AFTERNOON AND EVENING HRS.

INSPECTION OF SEVERAL BUFKIT FCST SOUNDINGS ALONG WITH 12Z
SOUNDINGS FROM BUF/PIT/ALB STILL SHOW DECENT MID-LEVEL LAPSE
RATES ALOFT ALONG WITH A FAIR AMOUNT OF DRY AIR ABOVE THE 600-HPA
LEVEL. THAT COMBINED WITH RECENT WATER VAPOR TRENDS SHOWING
ADDITIONAL MID-LEVEL DRYING APPROACHING FROM THE WEST SUGGEST THAT
IF SEVERE WX WERE TO DEVELOP...THE MAIN CONCERN WOULD BE STRONG
DOWNDRAFT WINDS. CONSIDERING THAT 0-6KM BULK SHEAR VECTORS REMAIN
ORIENTED PARALLEL TO BOTH THE FRONT AND PRE-FRONTAL
TROUGH...UPSCALE DEVELOPMENT INTO SHORT BOWING SEGMENTS OR A
CONGEALED LINE CANNOT BE RULED OUT. SPC MAINTAINS A SLGT RISK
ACROSS CENTRAL AND EASTERN PORTIONS OF THE FCST AREA AND
CONSIDERING THE STRENGTH OF THE WIND FIELD ALOFT...IF STORMS WERE
TO GET ORGANIZED...SEVERE CERTAINLY APPEARS POSSIBLE.

COLD FRONT TO BLOW THROUGH THE REGION LATER THIS EVENING WITH AN
ABRUPT WIND SHIFT TO THE NORTHWEST SIGNALING THE ARRIVAL OF MUCH
COOLER AIR FROM SOUTHERN CANADA. DESPITE PASSAGE OF THE
FRONT...RAIN WILL CONTINUE ACROSS THE AREA AS FRONT APPEARS TO
HAVE ANAFRONT CHARACTERISTICS ALONG WITH ADDITIONAL SUPPORT
PROVIDED BY THE NEXT ARRIVING UPSTREAM WAVE NOTED OVER THE
WESTERN GREAT LAKES THIS AFTERNOON. FOR THIS REASON...WILL
MAINTAIN HIGH LIKELY POPS ACROSS THE REGION THROUGH MID MORNING
FRIDAY BEFORE SHOWING A STEADY DECREASE FROM WEST TO EAST. TRICKY
FCST WITH RESPECT TO OVERNIGHT LOWS AS COOLER AIR WILL BE SETTLING
INTO THE REGION DURING THE EARLY MORNING HRS. FOR NOW...GENERALLY
FOLLOWED AVAILABLE MET/MAV GUIDANCE WITH UPPER 40S TO LOWER 50S
FCST.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
EARLY MORNING RAINS SHOULD SLOWLY COME TO AN END FROM WEST TO EAST
FRIDAY MORNING AS COOLER AND DRIER AIR CONTINUES ADVECTING ACROSS
OUR REGION. EXPECT A FAIRLY BRISK AND COOL DAY WITH NORTHWEST
WINDS OF 10-20 MPH WITH GUSTS AS HIGH AS 30 KTS NOT OUT OF THE
QUESTION. RAIN POSSIBILITIES TO CONTINUE ACROSS THE EASTERN ZONES
THROUGH THE AFTERNOON AS UPPER WAVE CONGEALS INTO A CLOSED UPPER
LOW WHICH WILL SLOWLY MIGRATE EAST INTO WESTERN NEW ENGLAND THIS
WEEKEND.

MAIN CONCERN GOING INTO THE WEEKEND WILL BE LIKELY FROST/FREEZE
CONCERNS AS MUCH COOLER AIR SETTLES IN FOR THE UPCOMING WEEKEND.
NEW GUIDANCE NOW SUGGESTING OVERNIGHT LOWS FALLING WELL INTO THE
MIDDLE TO UPPER 30S BOTH SAT/SUN NIGHTS WITH LOW 30S NOT OUT OF
THE QUESTION ACROSS THE TRADITIONALLY FAVORED COOLER LOCATIONS.
WE DEFINITELY EXPECT THE NEED FOR FROST/FREEZE HEADLINES BUT WILL
ALLOW LATER SHIFTS TO HANDLE THIS AS A RESULT DISTANCE INTO THE
FCST PERIOD. IN GENERAL THOUGH...AN UNSEASONABLY COOL HOLIDAY
WEEKEND SHAPING UP FOR THE REGION.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
UPR LOW SLOWLY LIFTS NWRD OUT OF NEW ENG WHILE A NLY FLOW OF COLD
AIR CONTS OVER THE FCST AREA. STRONG SUN ANGLE HELPS TOP MODIFY
THE AIR MASS BUT IT WILL STILL BE COOLER THAN NRML FOR THE
REMAINDER OF THE HOLIDAY WEEKEND. NEXT CHANCE OF RAIN ARRIVES LATE
TUE INTO WED AS THE HI RETREATES AND WRM FNT OVER THE MIDWEST
PUSHES NE. MUCH WRMR AIR RETURNS FOR WED AND WITH THE FNT STILL
OVER NRN NY AND WRN NEW ENG...PSBLTY OF SOME TRWS THRU THE END OF
THE PD.

MODEL GUID IN LINE WITH HPC GUID WHICH WAS FOLLOWED FOR THIS FCST.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
00Z UPDATE...
LINE OF HEAVY SHOWERS AND EMBEDDED THUNDER WILL FINISH EXITING THE
AREA THE NEXT COUPLE HOURS...INCLUDING HITTING KAVP WITH BRIEF IFR
CONDITIONS. BEHIND THE MAIN LINE...ADDITIONAL SCATTERED SHOWERS
WILL STILL OCCUR TAKING MOST TERMINALS IN AND OUT OF MVFR ALONG
WITH FLUCTUATING WIND. HOWEVER...THE ACTUAL SURFACE COLD
FRONT...WHICH AT 00Z IS STILL PROGRESSING THROUGH WESTERN
NY...WILL DRAG OVER THE AREA LATER THIS EVENING WITH A QUICK
LOWERING OF CIGS TO FUEL ALTERNATE MVFR LEVELS AND VEERING OF
PREDOMINANT WIND TO NORTHWEST. CIGS MAY EVEN GET INTO IFR LEVELS
DURING PREDAWN HOURS KBGM-KITH. NOT IN TAFS FOR OTHER TERMINALS
BECAUSE OF LOWER LIKELIHOOD...YET ALSO NOT OUT OF THE QUESTION.
A RAW DAY WITH COLD UPPER LEVEL LOW SLOGGING OVER THE REGION
FRIDAY. THIS WILL INCLUDE MVFR CIGS...OCCASIONAL SHOWERS /THOUGH
DIMINISHING WEST TO EAST THROUGH THE DAY/...AND NW TO NNW WINDS
WITH GUSTS 20-25 KTS.

OUTLOOK...

FRI NGT/EARLY SAT...PSBL LINGERING MVFR CIGS AND SCT SHRA FOR
KBGM...KAVP...AND KRME.

SAT MID MORNING THROUGH TUE...VFR.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...CMG
NEAR TERM...CMG/DGM
SHORT TERM...CMG
LONG TERM...DGM
AVIATION...MDP