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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 220436
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
1236 AM EDT WED MAY 22 2013

.SYNOPSIS...
-- Changed Discussion --
AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS THE NORTH COUNTRY
THROUGH THURSDAY. THE FRONTAL BOUNDARY THAT WAS STALLED TO OUR
SOUTH WILL RETURN NORTHWARD AS A WARM FRONT EARLY WEDNESDAY.
THE ASSOCIATED WARM AND MOIST AIR MASS FOR WEDNESDAY AND THURSDAY
WILL BRING ADDITIONAL ROUNDS OF THUNDERSTORMS BOTH WEDNESDAY AND
THURSDAY AFTERNOON. BRIEF HEAVY DOWNPOURS WILL BRING OVER AN INCH
OF RAIN TO MOST SECTIONS OF THE NORTH COUNTRY OVER THE NEXT 24 TO
48 HOURS. TEMPERATURES WILL GENERALLY BE ABOVE NORMAL OVER THE NEXT
SEVERAL DAYS. A COOLER AND DRIER AIR MASS IS EXPECTED TO RETURN
FOR THE UPCOMING HOLIDAY WEEKEND.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
-- Changed Discussion --
AS OF 1230 AM EDT WEDNESDAY...LAST ROUND OF SHOWER ACTIVITY FOR
THE OVERNIGHT HRS NOW PROGRESSING EWD THROUGH THE NRN ADIRONDACKS
AND CHAMPLAIN VALLEY AT 0430Z. IT APPEARS THE STRONGER CONVECTION
EARLIER IN THE EVENING HAS LARGELY STABILIZED THE AIR MASS AT THIS
POINT...WITH LITTLE CG OR IC LIGHTNING ACTIVITY DURING THE PAST
HOUR ACROSS OUR FORECAST AREA. HAVE ADJUSTED POPS BASED ON TRENDS
AND MENTIONING JUST A SLIGHT CHANCE OF TSTMS. A QUICK 0.50-0.75"
OF RAINFALL IS POSSIBLE DURING THE NEXT 1-3 HOURS BEFORE ACTIVITY
EXITS EASTWARD. NOTED 0.69" BETWEEN 03-04Z AT KSLK.

ADDED PATCHY FOG AREAWIDE GIVEN LIGHT WINDS AND SATURATED LOW-
LEVEL CONDITIONS IN THE WAKE OF LAST ROUND OF SHOWERS AND ISOLD
TSTMS. LOWS GENERALLY MID 50S TO UPR 50S.
-- End Changed Discussion --

&&

.SHORT TERM /8 AM THIS MORNING THROUGH THURSDAY NIGHT/...
AS OF 415 PM EDT TUESDAY...NORTH COUNTRY GENERALLY IN THE WARM
SECTOR ON WEDNESDAY AS FRONTAL ZONE RETREATS BACK NORTH OF THE
INTL BORDER. DIFFICULT TO SEE MUCH IN THE WAY OF LOW-LEVEL
CONVERGENCE...AND MID-LEVEL FLOW HAS SLIGHT ANTICYCLONIC
CURVATURE. PBL DEWPOINTS DO INCREASE INTO THE LOW 60S...AND WITH
PARTIAL SUN CONDITIONS SHOULD RESULT IN SBCAPE VALUES AROUND 1000
J/KG. AGAIN...MARGINAL/WEAK FORCING IN PLAY SO WHILE POTENTIAL FOR
ORGANIZED STORMS IS LOW...ISOLD TO SCT -TSRA IS POSSIBLE...LIKELY
PEAKING WITH DAYTIME HEATING MAX IN THE MID-LATE AFTN HOURS. A FEW
STRONGER STORMS MAY PRODUCE SMALL HAIL WITH LOCALLY HEAVY
DOWNPOURS. VALLEY HIGHS ON WEDNESDAY WILL REACH THE UPR 70S TO
AROUND 80.

POSITIVE TILTED UPR TROUGH AND COLD FRONTAL ZONE APPROACHES SLOWLY
LATE WEDNESDAY NIGHT INTO THURSDAY. THIS SHOULD GENERATE A MORE
WIDESPREAD THREAT OF SHOWERS AND TSTMS BY THURSDAY AFTN. DEEP-
LAYER SWLY FLOW IN ADVANCE OF THE FRONTAL BNDRY WILL ENSURE
MOISTURE/SOME INSTABILITY ON THURSDAY...THOUGH MID-LEVEL LAPSE
RATES WILL BE RELATIVELY POOR AROUND 6 C/KM. WITH PEAK
HEATING...MAY BE SUFFICIENT FOR A SEVERE STORM OR TWO WITH GUSTY
WINDS AND MARGINALLY SVR HAIL DURING THURSDAY AFTN...ESPECIALLY
CENTRAL/S-CENTRAL VT BASED ON CURRENT INDICATIONS. HIGHS THURSDAY
WILL RANGE FROM THE MID-UPR 70S ACROSS VT TO THE UPR 60S TO NEAR
70F IN THE NRN ADIRONDACKS.

COLD FRONT WILL FINALLY CROSS THE FORECAST AREA THURSDAY
NIGHT...THOUGH UPPER LEVEL TROF AND LOW WILL TRAIL BEHIND. SLOW
MOVING FLOW CONTINUES AS SURFACE LOW SLOWLY CREEPS EASTWARD AWAY
FROM THE REGION. CHANCE FOR SHOWERS FINALLY DECREASES AT THE END
OF THE PERIOD THURSDAY NIGHT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 225 PM EDT TUESDAY...DEPARTING LOW PRESSURE SYSTEM WILL
HAVE POSITIVELY TILTED UPPER LEVEL TROUGH MOVE OVER THE NORTH
COUNTRY ON FRIDAY...KEEPING CHC OF SHOWERS OVER MUCH OF THE AREA.
LATE FRIDAY IN TO FRIDAY NIGHT...TROUGH LOOKS TO TILT NEUTRAL TO
NEGATIVE AS THE SFC LOW PUSHES OFF THE NEW ENGLAND COAST. SFC LOW
TRAVERSES NEWD NEAR NEWFOUNDLAND...KEEPING BACK/WRN EDGE OF
PRECIP NEAR VT...THEREFORE HAVE KEPT SLGT CHC POPS OVER VT FRIDAY
NIGHT THROUGH FIRST HALF OF SATURDAY. AS HIGH PRESSURE BUILDS
OVER SW HUDSONS BAY...EXTENDING SWD OVER THE CENTRAL GREAT
LAKES...A SHORTWAVE ROTATING ABOUT THE UPPER LEVEL LOW OVER NEW
ENGLAND WILL BE FAIRLY DRY BUT BRING CLOUDS FOR THE REST OF
SATURDAY INTO SATURDAY NIGHT. ON SUNDAY...SOME TROUGHINESS
REMAINING OVER ERN ZONES...WITH CLOUDS OVER MOST OF VT. THE SFC
HIGH PRESSURE AND SOME UPPER LEVEL RIDGING WILL TAKE HOLD OF THE
REGION FOR THE REST OF THE PERIOD.

BELOW NORMAL MAX TEMPS WILL GRADUALLY TREND WARMER THROUGHOUT THE
PERIOD WITH MIN TEMPS GENERALLY IN THE 40S.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 00Z THURSDAY...COMPLEX FORECAST AS LOW LEVEL MOISTURE
CONTINUES OVER MUCH OF THE AREA ALONG WITH CHANCE OF SHOWERS AND
SOME THUNDERSTORMS THROUGH THE PERIOD. WARM FRONT SOUTH OF
FORECAST AREA THIS EVENING WILL LIFT NORTH ACROSS THE FORECAST
AREA OVER THE NEXT 24 HOURS. CIGS LOWERING TO MVFR TONIGHT WITH
IFR POSSIBLE...ESPECIALLY SLK/MPV/MSS. VSBYS LOWERING TO IFR IN
SHOWERS AND SCATTERED THUNDERSTORMS. LINE OF STRONG TO SEVERE
THUNDERSTORMS THIS EVENING...WITH MORE WIDESPREAD SHOWERS AND
EMBEDDED THUNDER OVERNIGHT. THUNDERSTORMS WEDNESDAY AFTERNOON MAY
ALSO BE ACCOMPANIED BY GUSTY WINDS.

OUTLOOK 00Z THURSDAY THROUGH SUNDAY...OCCASIONAL SHOWERS WITH
EMBEDDED THUNDERSTORMS WILL CONTINUE WEDNESDAY NIGHT INTO
THURSDAY. VFR WITH PERIODS OF MVFR/IFR IN HEAVIER SHOWERS.
SHOWERS AND MVFR CONDITIONS STILL POSSIBLE FRIDAY BEFORE SURFACE
HIGH PRESSURE BUILDS IN OVER THE WEEKEND WITH MAINLY VFR
CONDITIONS.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...BANACOS/NEILES
NEAR TERM...BANACOS/RJS
SHORT TERM...BANACOS/NEILES
LONG TERM...KGM
AVIATION...RJS/KGM