-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 220757
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
357 AM EDT TUE JUL 22 2014

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ATOP THE REGION TODAY INTO TONIGHT WITH
WARM AND DRY WEATHER CONTINUING. A COLD FRONT WILL APPROACH AND
CROSS THE AREA WEDNESDAY INTO WEDNESDAY EVENING WITH SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS...A FEW OF WHICH MAY BE STRONG TO
LOCALLY SEVERE. BEHIND THE FRONT...A RETURN TO MAINLY DRY AND
SEASONAL WEATHER IS EXPECTED BY THURSDAY INTO THE FIRST HALF OF THE
UPCOMING WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 330 AM EDT TUESDAY...ANOTHER MAINLY SUNNY AND WARM DAY ON TAP
FOR THE REGION AS DEEP LAYER HIGH PRESSURE REMAINS ACROSS THE
REGION. BUILDING HEIGHTS AND MID/UPPER LEVEL ANTICYCLONIC FLOW
SHOULD FOSTER BROAD SCALE SUBSIDENCE...SO LOOKING AT ONLY A FEW
FAIR WX SHALLOW CUMULUS CLOUDS...MAINLY ACROSS THE HIGHER TERRAIN
WITH NIL POPS. MODEL AVERAGED 18-00Z 925 MB TEMPS SUPPORT HIGHS
WELL INTO THE 80S WITH A FEW SPOT L90S IN THE BROADER VALLEYS.
WINDS LIGHT.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...QUIET WX CONTINUES TONIGHT AS HIGH
PRESSURE SLIDES SLOWLY EAST AND OFFSHORE...MAINTAINING A LIGHT
SOUTHERLY FLOW ACROSS THE REGION. AN APPROACHING COLD FRONT TO OUR
WEST MAY TEND TO SPREAD SCT MID TO HIGH LEVEL CLOUD COVER INTO OUR
WESTERN COUNTIES LATER AT NIGHT...BUT OUTSIDE A STRAY SLV SHOWER
TOWARD SUNRISE WE`LL REMAIN DRY OVERNIGHT. LOWS CONTINUE MILD
GENERALLY IN THE 60S TO LOCALLY NEAR 70F IN THE CHAMPLAIN VALLEY.

BRIEF...THOUGH ACTIVE PERIOD OF WEATHER THEN DEVELOPS DURING
WEDNESDAY INTO EARLY WEDNESDAY EVENING AS AFOREMENTIONED COLD FRONT
MAKES STEADY PROGRESS THROUGH THE AREA. DECENT 0-6KM SHEAR PROFILES
AND AMPLE PBL INSTABILITY IN EXCESS OF 1000 J/KG SHOULD BE MORE THAN
ENOUGH TO SUPPORT SCT/NUMEROUS SHOWERS AND STORMS ACROSS THE
AREA...A FEW OF WHICH MAY BECOME STRONG TO LOCALLY SEVERE.
PRE-FRONTAL CLOUDS AND MORNING SHOWERS MAY LIMIT THREAT ACROSS THE
SLV AND TO SOME EXTENT THE ADIRONDACKS...BUT SUCH SUBTLE TIMING
DIFFERENCES WILL BE ALLOWED TO PLAY OUT AND HAVE MENTIONED THIS
THREAT IN ALL AREAS FOR NOW...IN CLOSE AGREEMENT TO SPC SWODY2.
GUSTY/STRONG WINDS AND HEAVY DOWNPOURS (PWATS TO NEAR 2") APPEAR TO
BE THE MAIN THREAT WITH LARGE HAIL A LESSER CONCERN GIVEN DEEPER WCD
VALUES AND WBZ HEIGHTS ABOVE 11 KFT. CONVECTIVE MODE WOULD BE LINEAR
WITH POSSBL QLCS DEVELOPMENT ACROSS OUR EASTERN COUNTIES WITH
RELATIVELY UNIDIRECTIONAL WIND PROFILES THROUGH THE PBL. ALSO CAN`T
RULE OUT LOCALIZED HYDRO CONCERNS GIVEN THE WCD DEPTHS AND HIGH PWAT
VALUES...BUT WIND FIELDS APPEAR STRONG ENOUGH TO KEEP MOST OF THE
ACTIVITY MOVING ALONG AND GIVEN THE RELATIVELY DRY ANTECEDENT
CONDS MOST WATERSHEDS SHOULD BE ABLE TO HANDLE THINGS OK.

BY WEDNESDAY NIGHT SFC FRONT CLEARS EAST AND SOUTH WITH
SHOWERS/STORMS ENDING ACROSS OUR SOUTHERN VT COUNTIES BY MIDNIGHT OR
SO AND SKIES GRADUALLY TRENDING PC/CLR ACROSS THE NORTH OVERNIGHT.
LOWS A BLEND OF MODEL GUIDANCE...MAINLY 50S.

SFC HIGH PRESSURE THEN BUILDS EAST/SOUTH INTO THE FORECAST AREA BY
THURSDAY WITH CYCLONIC FLOW PERSISTING ALOFT UNDER BASE OF MEAN ERN
CANADA UPPER LONGWAVE TROUGH. UPWARD MOISTURE FLUXES FROM PRIOR
EVENING`S RAINFALL COMBINED WITH STRONG JULY SUN SHOULD LEAD TO
DECENT COVERAGE OF FAIR WX CUMULUS CLOUDS...ESP ACROSS THE HIGHER
TERRAIN. HOWEVER...ALL AND ALL A VERY NICE DAY IS EXPECTED WITH
LOWER HUMIDITY VALUES AND LIGHT NORTHERLY BREEZES AS HIGHS RANGE
THROUGH THE 70S.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
-- Changed Discussion --
AS OF 357 AM EDT TUESDAY...FAIRLY GOOD AGREEMENT AMONGST THE 00Z
GUIDANCE SUITE FOR THE LATTER PART OF THE WEEK INTO THE EARLY
WEEKEND. THEREAFTER DETAIL DIFFERENCES EMERGE BETWEEN 00Z
GFS...ITS ENSEMBLE MEAN AND 00Z ECMWF IN THE EVOLUTION AND
ULTIMATE RETROGRESSION OF A NORTHEASTERN NOAM MID-LEVEL TROUGH FOR
LATE WEEKEND/EARLY NEXT WEEK. THE SOURCE OF THOSE DIFFERENCES
STEMS FROM HOW QUICKLY TO PHASE A SHEARING-OUT SHORTWAVE ENTERING
THE CANADIAN PRAIRIES WITH THE EASTERN NOAM TROUGH. OVERALL
PATTERN FAVORS UNSETTLED CONDITIONS LATE WEEKEND INTO EARLY NEXT
WEEK WITH CLOUDY/OFF-AND-ON SHOWERS AND THUNDER - BUT NOTHING THAT
SEEMS TOO SIGNIFICANT. DESPITE PREVAILING CYCLONIC MID-LEVEL FLOW
THROUGH MUCH OF THE PERIOD...TEMPS WILL TEND TO RUN AROUND NORMAL.

MOSTLY CLEAR SKIES AND LIGHT SFC WINDS THURSDAY NIGHT SHOULD
PROMOTE STRONG RADIATIONAL COOLING. THURDSDAY NIGHT LOOKS TO BE THE
COOLEST NIGHT IN THE PERIOD (MID 40S TO VALLEY MID 50S). I DIDN`T
INTRODUCE INTO THE FORECAST YET BUT RIVER VALLEY FOG LOOKS TO BE A
GOOD POSSIBILITY THURS NIGHT AS WELL GIVEN WET SOIL CONDITIONS FROM
EXPECTED RAINFALL WEDNESDAY/WED NIGHT. CYCLONIC FLOW ALOFT COMBINED
WITH DAYTIME HEATING FRIDAY WILL LIKELY PRODUCE AT LEAST PARTLY
CLOUDY SKIES WITH SLIGHT CHANCE TO CHANCE POPS MORE FOCUSED TO THE
HIGHER TERRAIN. THERE ISN`T MUCH MOISTURE TO WORK WITH BUT COULDN`T
REALLY DISCOUNT SOME ISOLATED TO SCATTERED SHOWERS. OPTED FOR A DRY
FORECAST FOR THE FIRST HALF OF SATURDAY AS THE MID-LEVEL TROUGH AXIS
PIVOTS NORTHEAST WITH NEUTRAL TO SLIGHT HEIGHT RISES. THE REST OF
THE WEEKEND INTO EARLY NEXT WEEK HAS SLIGHT CHANCE/CHANCE POPS
GRADUALLY INCREASING TO HIGH-CHANCE TOWARD EARLY NEXT WEEK AS THE
LARGE-SCALE TROUGH RETROGRADES TOWARD THE GREAT LAKES...LEAVING THE
NORTH COUNTRY UNSETTLED IN SOUTHWEST FLOW ALOFT. TEMPS FOR SATURDAY
INTO TUESDAY PRETTY SIMILAR...HIGHS IN THE 70S TO LOW 80S AND LOWS
IN THE 50S TO LOW 60S.
-- End Changed Discussion --

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
THROUGH 06Z WEDNESDAY...IFR TO VLIFR FOG/MIST AT SLK AND
EVENTUALLY DEVELOPING AT MPV...OTHERWISE VFR FOR THE REST OF THE
TAF PERIOD. AREA OF SCT-BKN MID-LEVEL CLOUDS ACROSS THE WESTERN
HALF OF VERMONT WILL HELP DELAY MIST OR FOG DEVELOPMENT AT MPV
UNTIL AFTER 08Z WHEN THOSE CLOUDS BEGIN TO THIN OUT/MOVE EAST.
BUILDING UPPER RIDGING AND ASSOCIATED SUBSIDENCE ALOFT LIKELY TO
SUPPRESS AFTERNOON CU DEVELOPMENT EXCEPT AT MPV/SLK IN CLOSER
PROXIMITY TO TERRAIN. WILL START TO SEE SOME INCREASE IN CIRRUS
TOWARDS TUESDAY EVENING PARTICULARLY AT MSS AND SLK. WINDS BECOME
SOUTHERLY TUESDAY GENERALLY UNDER 10 KTS.

OUTLOOK 06Z WEDNESDAY THROUGH SATURDAY...

06Z WED - 12Z WED...VFR THOUGH WITH INCREASING CLOUDS. POSSIBLE
MARGINAL LLWS AT MSS AS WIND FIELDS STRENGTHEN OVERNIGHT.

12Z WED - 06Z THU...VFR TRENDING TO MVFR/IFR IN SHOWERS/STORMS AS
A COLD FRONT TRACKS THROUGH THE REGION...MAINLY WEDS
AFTERNOON/NIGHT. SOME STORMS MAY BE STRONG WITH
TURBULENCE...GUSTY WINDS AND SMALL HAIL.

06Z THU - 00Z FRI...LINGERING MVFR SHOWERS POSSIBLE INTO THURSDAY
MORNING...THEN TRENDING MAINLY DRY THEREAFTER AS FRONT SINKS
SOUTHWARD AWAY FROM THE AREA.

00Z FRI - 00Z SUN...VFR UNDER SURFACE HIGH PRESSURE. AN ISOLATED
AFTERNOON SHOWER OVER THE HIGHER TERRAIN IS POSSIBLE.

&&

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

&&

$$
SYNOPSIS...JMG
NEAR TERM...JMG
SHORT TERM...JMG
LONG TERM...LOCONTO
AVIATION...KGM/LOCONTO