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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 211904
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
304 PM EDT MON JUL 21 2014

.SYNOPSIS...
SURFACE HIGH PRESSURE WILL CONTINUE TO BE LOCATED OVER EASTERN NEW
ENGLAND TODAY...WITH WARM SOUTHERLY WINDS ACROSS OUR REGION. THIS
WILL HELP PUSH TEMPERATURES INTO THE 80S WITH SOME INCREASE IN THE
RELATIVE HUMIDITY LEVELS. A POP UP ISOLATED SHOWER WILL BE POSSIBLE
DURING THE AFTERNOON HOURS ACROSS NORTHERN NEW YORK AND
VERMONT...BUT COVERAGE WILL BE LIMITED. A BETTER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL ARRIVE WEDNESDAY AFTERNOON AND EVENING
ASSOCIATED WITH A COLD FRONT.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 134 PM EDT MONDAY...COMPOSITE RADAR LOOP SHOWING A FEW
WIDELY SCATTERED LIGHT RAIN SHOWERS OVER THE ADIRONDACKS AT THIS
TIME. VISIBLE SATELLITE LOOP SHOWING PLENTY OF CUMULUS CLOUDS
ACROSS NORTHERN NEW YORK AT THIS TIME AND ALONG THE WESTERN SLOPES
OF THE GREEN MOUNTAINS. CURRENT FORECAST IS IN GENERALLY GOOD
SHAPE...SO NO MAJOR CHANGES MADE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
AS OF 350 AM EDT MONDAY...

AN ACTIVE WEATHER DAY IS EXPECTED ON WEDS...WITH STRONG TO
POSSIBLE SVR STORMS.

MID/UPPER LVL RIDGE BUILDS FROM THE OHIO VALLEY INTO THE NE CONUS ON
TUESDAY...AHEAD OF POTENT S/W ENERGY AND ASSOCIATED TROF ACRS THE
NORTHERN PLAINS. THE COMBINATION OF BUILDING HGHTS...WARMING MID LVL
TEMPS/CAP...AND VERY DRY SOUNDING PROFILES WL LIMIT PRECIP CHCS ON
TUESDAY. WL MENTION JUST SCHC (20%) ACRS THE MTNS...BUT THINKING CWA
WL REMAIN DRY. PROGGED 85H TEMPS CLIMB BTWN 15-17C BY 00Z
WEDS...SUPPORTING HIGHS IN THE L80S MTNS/NEK TO NEAR 90F CPV/SLV AND
LWR CT RIVER VALLEY. THESE TEMPS WITH DWPTS READINGS IN THE 60S...WL
RESULT IN HEAT INDEX VALUES IN THE L90S ACRS THE WARMER VALLEY
LOCATIONS. A WARM AND MUGGY NIGHT IS EXPECTED ON TUES NIGHT/WEDS
MORNING WITH SOUTHERLY FLW AND DWPT TEMPS IN THE 60S. LOWS WL RANGE
FROM THE U50S DEEPER MTN VALLEYS TO NEAR 70F IN THE CPV/SLV.

MANY INGREDIENTS COMING TOGETHER FOR SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS ON WEDS...WITH SOME STRONG TO POSSIBLY SEVERE.
SYNOPTIC SCALE SHOWS DEVELOPING MID/UPPER LVL TROF ACRS THE CENTRAL
GREAT LAKES WITH POTENT 5H VORT APPROACHING THE SLV BY 18Z WEDS.
THIS TROF WL HELP INCREASE THE MID/UPPER LVL WIND FIELDS ACRS OUR
REGION LATE ON WEDS AFTN...WITH 0 TO 6 KM SHEAR VALUES BTWN 30 AND
40 KNOTS. ALSO...HAVE NOTED 500MB WINDS INCREASE TO 40 KNOTS ACRS
NNY BY 18Z WEDS. AT THE SFC A WELL DEFINED SFC COLD FRNT WITH
CONVERGENCE WL BE LOCATED ACRS THE SLV/NNY AT 18Z...AND THRU MOST OF
OUR CWA BY 00Z THURS. THIS TIMING ALONG WITH THE POTENT S/W ENERGY
WL BE DURING PEAK HEATING/GREATEST INSTABILITY...HELPING WITH ROBUST
UPDRAFTS AND STORM DEVELOPMENT. NAM PROGGED SFC BASED CAPE VALUES
ARE BTWN 1500 AND 2000 J/KG WITH LIS VALUES AROUND -5C...WITH SOME
HINTS AT A WEAK ELEVATED MIXED LAYER...WITH MODEST MID LVL LAPSE
RATES. SOUNDINGS CONT TO SUPPORT A UNIDIRECTIONAL FLW FROM SFC THRU
500MB...RESULTING IN ORGANIZED LINE SEGMENTS OF STORMS/MULTI CELLS.
THE PRIMARY SVR WX THREAT WL BE DAMAGING WINDS...WITHIN ANY BOWING
LINE SEGMENT. WL UPDATED HWO AND MENTION THE POTENTIAL FOR SVR.
STILL ENOUGH UNCERTAINTY IN TIMING OF SYSTEM AND MAGNITUDE OF
INSTABILITY/SHEAR TO NOT MENTION SVR IN THE ZONES ATTM.
ALSO...WITH PWS BTWN 1.75 AND 1.90" AND WARM CLOUD DEPTHS
APPROACHING 12,000 FEET...LOCALIZED HEAVY DOWN POURS WL BE LIKELY.
PROGGED 85H TEMPS REMAIN UNCHANGED AHEAD OF BOUNDARY FOR
WEDS...AROUND 16C SUPPORTING HIGHS MAINLY IN THE 80S TO AROUND 90
IN THE WARMER VALLEYS. LATE MORNING/EARLY AFTN CUMULUS DEVELOPMENT
MAY LIMIT FULL HEATING POTENTIAL.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
AS OF 303 PM EDT MONDAY...OVERALL CONDITIONS FOR THE EXTENDED
PERIOD WILL TREND DRIER AND MORE SEASONAL AS SURFACE HIGH
PRESSURE BUILDS INTO THE REGION THURSDAY AND REMAINS THROUGH AT
LEAST SATURDAY. ALOFT WE REMAIN UNDER CYCLONIC FLOW FROM AN UPPER
LOW/TROUGH SITUATED NORTH OF THE BORDER WHICH WILL RESULT IN
GENERALLY PARTLY CLOUDY SKIES DURING THE DAY AND RELATIVELY CLEAR
NIGHTS. AS THE FLOW TURNS FROM THE SOUTHWEST THURSDAY TO
WEST/NORTHWEST FOR FRIDAY AND SATURDAY...WEAK EMBEDDED SHORTWAVE
ENERGY MAY BRING AN ISOLATED SHOWER OR TWO TO THE HIGHER TERRAIN
OF THE DACKS AND GREENS...BUT GIVEN THE RELATIVELY DRY LOW LEVELS
WILL CONTINUE TO CARRY JUST SOME SLIGHT CHANCE POPS AT THIS TIME
WITH MOST AREAS LIKELY REMAINING DRY.

CONDITIONS TURN A BIT MORE UNSETTLED AS WE MOVE INTO THE
SUNDAY/MONDAY TIMEFRAME AS MEDIUM RANGE MODELS REMAIN IN GOOD
AGREEMENT SHOWING THE AFOREMENTIONED TROUGH RETROGRADING WESTWARD
INTO THE GREAT LAKES AND DEEPENING OVER TIME. THIS WILL MARK A
RETURN OF MID/UPPER MOIST SOUTH-SOUTHWESTERLY FLOW RENEWING
CHANCES FOR PRECIPITATION. OVERALL...RIGHT NOW DYNAMICS LOOK
PRETTY MEAGER SO NOT THINKING ANYTHING TOO SIGNIFICANT...JUST
SOME GARDEN VARIETY SHOWERS THUNDERSTORMS POSSIBLE.

TEMPS THROUGH THE PERIOD WILL BE VERY SEASONAL WITH HIGHS RANGING
FROM THE MID 70S TO LOW 80S...AND LOWS IN THE 50S. ONLY ABNORMAL
DAY WILL BE THURSDAY RIGHT BEHIND THE FRONT WHERE HIGHS WILL BE
ONLY IN THE 70S...AND LOWS THURSDAY NIGHT MIGHT TOUCH INTO THE
40S FOR SOME LOCATIONS.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
THROUGH 18Z TUESDAY...VFR CONDITIONS WILL PERSIST THROUGH THE
NEXT 24 HOURS. DIURNAL CUMULUS MOST ABUNDANT ACROSS THE HIGHER
TERRAIN OF THE DACKS AND GREENS THIS AFTERNOON WILL DISSIPATE
THIS EVENING/OVERNIGHT TO SKC...THEN BEGIN TO BUILD AGAIN AFTER
12-14Z TUESDAY. A WEAK DISTURBANCE IN THE FLOW ALOFT MAY SPARK AN
ISOLATED SHOWER ACROSS THE DACKS THIS AFTERNOON...BUT COVERAGE NOT
ENOUGH TO EVEN MENTION VCSH SO HAVE LEFT OUT OF FORECAST. LIGHT
TERRAIN AND LAKE DRIVEN WINDS THIS AFTERNOON ABATE OVERNIGHT AND
RETURN AFTER 12Z TUESDAY.

OUTLOOK 18Z TUESDAY THROUGH SATURDAY...

18Z TUE - 12Z WED...MAINLY VFR WITH AN ISOLATED TERRAIN DRIVEN
SHOWER POSSIBLE TUESDAY AFTERNOON.

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 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 ON THE HIGHER TERRAIN IS POSSIBLE.

&&

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

&&

$$
SYNOPSIS...TABER
NEAR TERM...WGH
SHORT TERM...TABER
LONG TERM...LAHIFF
AVIATION...LAHIFF