-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 160455
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
1255 AM EDT THU MAY 16 2013

.SYNOPSIS...
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IT WILL BE PARTLY CLOUDY OVERNIGHT WITH PATCHY FOG. AN UPPER
LEVEL LOW AND A WEAK SURFACE TROUGH WILL BRING ISOLATED TO
SCATTERED RAIN SHOWERS ACROSS THE NORTHERN HALF OF THE FORECAST
AREA DURING THURSDAY AFTERNOON. OTHERWISE...GENERALLY DRY WEATHER
CONDITIONS ARE EXPECTED OVER THE NEXT SEVERAL DAYS. TEMPERATURES
WILL BE NEAR TO SLIGHTLY ABOVE SEASONAL AVERAGES FOR MID-MAY
THROUGH THE UPCOMING WEEKEND.
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&&

.NEAR TERM /UNTIL 7 AM THIS MORNING/...
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AS OF 1245 AM EDT THURSDAY...OCCLUDED FRONT PUSHING EAST OF
FORECAST AREA AT THIS TIME. CLOUDS REMAIN OVER NORTHERN PORTIONS
OF FORECAST AREA WHILE MAINLY CLEAR SKIES PREVAIL OVER THE SOUTH
AND ACROSS THE SAINT LAWRENCE VALLEY. EXPECT A DECREASE IN CLOUD
COVER OVER NORTHERN AREAS OVERNIGHT. MINOR TWEAKS MADE TO HOURLY
PARAMETERS SUCH AS SKY AND TEMPS TO REFLECT LATEST DATA.
COMBINATION OF CLEARING SKIES...LIGHT WINDS AND WEDNESDAYS SHOWERS
ALLOWING FOR FORMATION OF FOG IN SOME AREAS...SO ADDED PATCHY FOG
TO FORECAST AS WELL.
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&&

.SHORT TERM /7 AM THIS MORNING THROUGH FRIDAY NIGHT/...
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AS OF 328 PM EDT WEDNESDAY...ON THURSDAY...CLOSED MID-LEVEL LOW
ROTATES EWD FROM SRN QUEBEC INTO NORTHERN MAINE...WITH MODERATELY
STRONG P-GRADIENT IN PLACE ACROSS THE NORTH COUNTRY. WITH DAYTIME
HEATING/MIXING...ANTICIPATE STEEP LAPSE RATES AND BREEZY/GUSTY
CONDITIONS FROM THE LATE MORNING THRU AFTN HOURS. LOOKING AT W-WNW
WINDS OF 15-25 MPH WITH GUSTS UP TO 35 MPH. SHALLOW INSTABILITY
COMBINED WITH WEAK TROUGH/COLD FRONTAL PASSAGE FROM NW-SE WILL BE
SUFFICIENT TO GENERATE ISOLD TO SCATTERED SHOWER ACTIVITY...MAINLY
DURING THURSDAY AFTN. BASED ON LOCAL WRF RUNS...SHOWER ACTIVITY
SHOULD BE MOST CONCENTRATED ACROSS NRN HALF OF THE FORECAST
AREA...AND NRN GREEN MTNS IN PARTICULAR...AND THEN DISSIPATE WHILE
MOVING SWD THRU CENTRAL VT TOWARD EARLY EVENING. HAVE INCLUDED
POPS 40-50 PERCENT FROM THE NRN ADIRONDACKS NEWD ACROSS THE
CHAMPLAIN VALLEY INTO N-CENTRAL VERMONT...WITH LESSER POPS TO THE
WEST AND SOUTH. RELATIVELY WARM AIR MASS IN PLACE SOUTH OF THE
TROUGH/COLD FRONT...AND WITH PARTIAL SUNSHINE WILL SEE HIGH TEMPS
IN THE LOW 70S FOR THE SRN CHAMPLAIN VALLEY AND IN THE CT RIVER
VALLEY. MID-UPR 60S EXPECTED ACROSS NRN NY AND NRN VT.

SHOWER ACTIVITY SHOULD DISSIPATE DURING THURSDAY EVENING WITH
GENERALLY DRY CONDITIONS FOR THE BALANCE OF THURSDAY NIGHT. LOWS IN
THE LOW-MID 40S WITH A FEW MID 30S VCNTY KSLK.

COULD BE A STRAY SHOWER OVER THE NRN MTNS FRIDAY AFTN WITH MINIMAL
INSTABILITY WITH DAYTIME HEATING. WILL MENTION ISOLD -SHRA OVER
THE NRN MTNS. GENERALLY TRANQUIL FRIDAY NIGHT WITH PARTLY CLOUDY
CONDITIONS AND LIGHT WINDS. LOW TEMPERATURES GENERALLY IN THE LOWER
40S WITH GOOD RADIATIONAL COOLING. MAY SEE SOME MID-UPR 30S IN THE
NORMALLY COLDER SPOTS IN THE NORTHEAST KINGDOM OF VERMONT AND
ACROSS THE NRN ADIRONDACKS.
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&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 400 PM EDT WEDNESDAY...BOTH GFS/ECMWF SHOW A BUSY MID/UPPER
LVL PATTERN ACRS THE EASTERN CONUS FOR DAYS 4 THRU 7...BUT DEEP
LAYER MOISTURE IS LIMITED UNTIL NEXT WEEK. THIS WL RESULT IN A
MAINLY DRY FCST THRU MONDAY...WITH INCREASING CHCS FOR PRECIP LATE
MONDAY THRU WEDS OF NEXT WEEK...ALONG WITH TEMPS TRENDING ABOVE
NORMAL. HAVE MENTIONED LOW CHC POPS ACRS NORTHERN VT ON SAT AFTN
ASSOCIATED WITH WEAK 5H VORT AND LOBE OF MID LVL RH ROTATING
AROUND CLOSED 5H/7H CIRCULATION ACRS EASTERN CANADA. BEST CHC WL
BE DURING PEAK DAYTIME HEATING AND OVERALL COVERAGE/INTENSITY OF
ANY SHOWERS WL BE LIMITED. OTHERWISE...MID/UPPER LVL RIDGE BUILDS
ACRS THE NE CONUS FOR SUNDAY THRU MONDAY...RESULTING IN DRY
CONDITIONS AND WARMING TREND. PROGGED 85H TEMPS CLIMB FROM 6C TO
10C BY 18Z MONDAY. THIS WL SUPPORT TEMPS IN THE M60S MTNS TO L70S
ON SATURDAY...WARMING INTO THE U60S MTNS/NEK TO M/U 70S WARMER
VALLEYS. HAVE USED A BLEND OF GMOS/ECE BC GRIDS TO POPULATE
TEMPS...TO BETTER SHOW TRRN AND COOLER LAKE CHAMPLAIN TEMPS. BY
LATE MONDAY INTO TUES...A SFC BOUNDARY WL SLOWLY DROP SOUTH TWD
OUR NORTHERN FA. THIS WL TIGHT THE NORTH/SOUTH THERMAL GRADIENT
ACRS OUR FA...ALONG WITH INCREASE THE DEEP LAYER 850 TO 500MB RH.
THIS INCREASE IN RH...COMBINED WITH SEVERAL 5H VORTS AND WEAK AREAS
OF SFC LOW PRES SLIDING ALONG SFC BOUNDARY WL ENHANCE OUR CHCS FOR
PRECIP...ESPECIALLY TUES INTO WEDS. FURTHERMORE...WITH MORE
CLOUDS/PRECIP AND DEVELOPING THERMAL GRADIENT TEMP FCST WL BECM
MORE COMPLEX TWD THE MID OF NEXT WK. TRIED TO SHOW A NORTH TO
SOUTH GRADIENT WITH HIGHS TRENDING BACK TWD NORMAL. ANTICIPATING
AT OR ABOVE NORMAL TEMPS FOR OVERNIGHT LOWS THRU THE PERIOD.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THROUGH 00Z FRIDAY...SHOWERS AND EMBEDDED THUNDER HAVE SINCE
ENDED ACROSS THE TAFS. DRYSLOT IS CURRENTLY IMPINGING INTO WESTERN
NEW ENGLAND WHICH IS HELPING TO LIFT CEILINGS ACROSS NORTH-
CENTRAL NEW YORK STATE. EXCEPT FOR SOME MVFR CEILINGS NEXT FEW
HOURS AT MPV BUT EXPECT THE BKN/OVC VFR CEILINGS TO THIN OUT IN
COVERAGE. ONE AREA WHICH WHERE BKN/OVC CEILINGS MAY HANG ON LONGER
IS AT MSS. SOUTH WINDS WILL VEER TO SOUTHWEST/WESTERLY WITH GUSTS
DROPPING OFF...THOUGH STILL EXPECT SUSTAINED WINDS OF 7-10KTS
THROUGH OVERNIGHT. THIS SHOULD PRECLUDE ANY MIST/FOG DEVELOPMENT
DESPITE RECENT RAIN.

EXPECT GENERALLY VFR CONDITIONS FOR THURSDAY. A WEAK SFC TROUGH
DROPS DOWN OUT OF CANADA 18-22Z THURSDAY AND MAY TRIGGER ISOLATED
TO SCATTERED SHOWERS WITH BRIEF MVFR VISIBILITY POSSIBLE. THREAT
OF SHOWERS AT ALL TAFS EXCEPT RUT. WEST WINDS 10-12KTS GUSTS UP TO
25 KTS THURSDAY...WITH SLIGHT VEER TO WEST-NORTHWEST LATE IN THE
DAY WITH SFC TROUGH PASSAGE.

OUTLOOK 00Z FRIDAY THROUGH MONDAY...
SFC HIGH PRES AND VFR CONDITIONS WL PREVAIL THRU THE WEEKEND.
HOWEVER...AS INSTABILITY INCREASES ON SUNDAY...A FEW AFTN/EVENING
SHOWERS WL BE POSSIBLE...ALONG WITH A BRIEF PERIOD OF MVFR.

&&

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

&&

$$
SYNOPSIS...BANACOS
NEAR TERM...RJS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER/LOCONTO