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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 291132
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
732 AM EDT TUE JUL 29 2014

.SYNOPSIS...
TODAY WILL BE PARTLY SUNNY WITH TEMPERATURES SLIGHTLY BELOW
NORMAL WITH A NORTHWEST FLOW OF AIR FROM CANADA. A SHOWER OR
ISOLATED THUNDERSTORM WILL BE POSSIBLE BOTH WEDNESDAY AND THURSDAY
AFTERNOONS WITH LOW PRESSURE OVER EASTERN CANADA. A RETURN TO MORE
NORMAL SUMMER WEATHER IS EXPECTED THIS WEEKEND WITH A SLIGHT
CHANCE OF AN AFTERNOON OR EVENING SHOWER OR THUNDERSTORM.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 731 AM EDT TUESDAY...NO CHANGES WITH THIS UPDATE.

WITH WEST TO NORTHWEST FLOW OF DRIER BEHIND DEPARTING LOW
PRESSURE BRINGING CLEARING THIS MORNING AS EVIDENT ON SATELLITE
AND SURFACE OBS.

WILL CALL IT PARTLY SUNNY TODAY AS EXPECTING WET GROUND WILL
SUPPLY SOME MOISTURE FOR SOME CU/SC DEVELOPMENT AS MODEL SOUNDING
SHOWING SHALLOW LOW-LEVEL INSTABILITY UNDER CYCLONIC FLOW ALOFT. A
CAPPING SUBSIDENCE INVERSION UP AROUND 10K FT MAY RESULT IN SC
SPREADING OUT TO LOW AC BUT HINDER ANY PRECIPITATION BUT MAY
RESULT IN A BIT MORE CLOUD COVER THAN GUIDANCE SUGGEST.

850 TEMPS UP TO ABOUT 8-9C THIS AFTERNOON SO EXPECTING HIGH TEMPS
FROM THE UPPER 60S IN THE HIGHER TERRAIN TO MID 70S IN THE LOWER
ELEVATIONS. WINDS WILL BE GENERALLY LIGHT WEST TO NORTHWEST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
AS OF 452 AM EDT TUESDAY...

CYCLONIC FLOW ALOFT CONTINUES THROUGH THIS PERIOD WITH THE BEST
CHANCE OF SHOWERS AND THUNDERSTORMS ON THURSDAY AS FAIRLY POTENT
SHORT WAVE AND COLD POCKET ALOFT (-18 TO -20C AT 500 MB) ROTATES
THROUGH NORTHERN NEW YORK AND NEW ENGLAND.

OTHER THAN SOME DISSIPATING DIURNAL CLOUDS THIS EVENING EXPECTING
SOME MOSTLY CLEAR SKIES TONIGHT WITH LOW TEMPS IN THE MID 40S IN
THE USUAL COLD SPOTS TO MID TO UPPER 50S NEAR LAKE CHAMPLAIN. ALSO
EXPECTING SOME PATCHY DENSE RIVER VALLEY FOG AFTER MIDNIGHT UNTIL
ABOUT 8 A.M. IN THE CLIMATOLOGICALLY FAVORED FOG PRONE LOCATIONS.

ON WED LITTLE CHANGE IN THE SYNOPTIC SCALE PATTERN IS
EXPECTED...SOME WEAK INSTABILITY ESPECIALLY ST. LAWRENCE VALLEY
WITH SLIGHTLY COOLER TEMPS ALOFT. RESULTING CAPE FROM THE THE
MODELS AVG ABOUT 300 J/KG AND SUPPORTS THE IDEA OF A CHANCE OF SHOWERS OR
AN ISOLATED RUMBLE OF THUNDER AS SOME OF THE CONVECTION ALLOWING
MODELS SHOWING CAPE AS HIGH AS 1000 J/KG AT KMSS. 850 TEMPS CHANGE
VERY LITTLE PERHAPS A DEGREE WARMER THAN TODAY NEAR 10C WITH HIGHS
MAINLY IN THE 70S.

AGAIN PARTLY CLOUDY SKIES WED NIGHT AND SOME PATCHY FOG POSSIBLE.

THURSDAY WILL FEATURE THE STRONGER SUPPORT ALOFT WITH DIFF VORT
ADVECTION AND COOLING ALOFT. ARW MEMBERS OF THE SREF ALL SHOWING
CAPE VALUES UP TO 750 J/KG WITH OTHER MEMBERS LESS. WITH FURTHER
COOLING ALOFT ON THURSDAY AND A LITTLE MORE HEATING COULD SEE SOME
CAPE VALUES OVER 1000 J/KG AS THE ECMWF INDICATES OVER VT. FURTHER
WEST IT MAY BE THE TIME OF THE SHORT WAVE IS A BIT TOO EARLY WITH
MOVER CLOUDS TO PREVENT SIGNIFICANT HEATING. HIGHS AGAIN IN THE
70S.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 452 AM EDT TUESDAY...

A FALL/WINTER/EARLY SPRING LOOK TO THE UPPER LEVEL PATTERN ACROSS
NOAM...DOMINATED BY A SLOW-MOVING/RETROGRADING UPPER LOW PARKED OVER
THE JAMES BAY REGION AND A BUILDING ATLANTIC RIDGE ALOFT.

THE PROXIMITY OF TROF AXIS ALOFT AND SURFACE WITH DAYTIME HEATING
WILL ACCOUNT FOR CHC SHRA/TSRA ON THE WEEKEND BUT HOPEFULLY
REMAINING DRY ON FRIDAY OR JUST ISOLATED IN NATURE.

UPPER LOW FINALLY WEAKENS AND SHIFTS EASTWARD INTO THE GULF OF SAINT
LAWRENCE SUNDAY WITH A WEAK RIDGE DEVELOPING ALOFT SUNDAY NIGHT INTO
MONDAY WITH SUNNIER/DRIER WEATHER EXPECTED.

TEMPERATURES WILL REMAIN AT SEASONABLE LEVELS THROUGH THE STRETCH
WITH 70S/L80S DURING THE DAY AND PRIMARILY 50S/L60S AT NIGHT WITH
SFC DEWPOINTS CREEPING BACK INTO U50S/L60S.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
THROUGH 12Z WEDNESDAY...MIXING WILL HELP BREAK UP CIGS AT
KMPV/KSLK THIS MRNG WITH VFR UNDER SCT SKIES EVERYWHERE WITH
WINDS <10 KTS TODAY. TNGT...VFR FOR MOST SITES WITH MVFR/IFR PSBL
FOR KMPV/KSLK WITH LGT VRBL WINDS.


AFT 12Z...GENERALLY VFR WITH WINDS AOB 10KTS.

OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY...

12Z THU - 00Z SUN...MAINLY VFR ALTHOUGH BRIEF PERIODS OF MVFR
POSSIBLE IN AN AFTERNOON SHOWER OR THUNDERSTORM.

&&

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

&&

$$
SYNOPSIS...SISSON
NEAR TERM...SISSON
SHORT TERM...SISSON
LONG TERM...SLW
AVIATION...SLW