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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 160158
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
958 PM EDT WED MAY 15 2013

.SYNOPSIS...
A WARM FRONT WILL SHIFT EASTWARD ACROSS THE NORTH COUNTRY THIS
EVENING BRINGING CLOUDY SKIES AND SCATTERED RAIN SHOWERS. GUSTY
SOUTH WINDS THROUGH THIS EVENING WILL SHIFT INTO THE WEST TONIGHT
WITH THE FRONTAL PASSAGE. THE LINGERING 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.

&&

.NEAR TERM /UNTIL 7 AM THURSDAY MORNING/...
-- Changed Discussion --
AS OF 958 PM EDT WEDNESDAY...MINOR ADDITIONAL TWEAKS TO SKY COVER
AS WELL AS WIND AND TEMP DATA THROUGH THE OVERNIGHT HOURS TO
ACCOUNT FOR CURRENT OBSERVATIONAL TRENDS. LITTLE OVERALL CHANGE TO
SENSIBLE FORECAST HOWEVER. PRIOR DISCUSSION FOLLOWS. HAVE A GREAT
NIGHT.

MODEST UPDATES TO PUSH CLOUDS AND
THREAT OF SHOWERS/ISOLATED THUNDER EAST FAIRLY QUICKLY EAST AND
OUT OF OUR AREA THIS EVENING PER CURRENT OBSERVATIONAL DATA. WARM
FRONT NOW EXITING OUR EASTERN COUNTIES AS OF 6 PM WITH
SCT/NUMEROUS SHOWERS ALONG AND EAST OF THE BOUNDARY. PRONOUNCED
DRIER AIR AT MID LEVEL CONTINUES TO PUSH EAST INTO OUR NRN NY
COUNTIES AS OF EARLY EVENING...AND EXPECT THIS TREND TOWARD PTLY
CLOUDY AND/OR MOSTLY CLEAR APPEARS REASONABLE ACROSS MOST OF THE
AREA AS WE PROGRESS INTO THE OVERNIGHT HOURS. INDEED...PORTIONS OF
THE SLV WHICH HAS SEEN SOME LATE AFTERNOON SUN HAS SEEN
TEMPERATURES REBOUND BACK INTO THE 60S TO AROUND 70F. THUS A WIDE
DISPARITY BETWEN THESE MILDER READINGS...AND RAIN-COOLED VALUES
FURTHER EAST. STILL EXPECT VALUES TO SETTLE BACK INTO THE 40S
OVERNIGHT UNDER LIGHT TO MODEST SOUTHERLY FLOW...SO HAVE BLENDED
CURRENT OBSERVATIONAL DATA IN WITH INHERITED DATABASE FROM ABOUT
08Z ONWARD. COULD SEE SOME ISOLATED/PATCHY FOG HERE OR THERE...BUT
ENOUGH WIND JUST OFF THE DECK TO KEEP ENHANCED MIXING GOING ATOP
THE NOCTURNAL BOUNDARY LAYER IN MOST SPOTS SO HAVE NOT INCLUDED
WHOLESALE MENTION AT THIS POINT.
-- End Changed Discussion --

&&

.SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
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.

&&

.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 /02Z 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...JMG
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...LOCONTO/TABER