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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 241921
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
321 PM EDT THU APR 24 2014

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE OVER THE NORTH COUNTRY TONIGHT WILL RESULT IN
MAINLY CLEAR SKIES AND COOL TEMPERATURES. FRIDAY WILL START WITH
PLENTY OF SUNSHINE BUT CLOUDS WILL DEVELOP DURING THE AFTERNOON
HOURS WITH SHOWERS ARRIVING FOR FRIDAY NIGHT INTO SATURDAY.
TEMPERATURES WILL BE NEAR NORMAL FOR FRIDAY...BUT BELOW NORMAL
WITH CLOUDS AND SHOWERS ON SATURDAY INTO SUNDAY.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
-- Changed Discussion --
AS OF 320 PM EDT THURSDAY...SFC HIGH PRES LOCATED OVER THE EASTERN GREAT
LAKES WL SHIFT INTO THE NORTH COUNTRY TONIGHT WITH CLRING SKIES
AND LIGHT TRRN DRIVEN WINDS DEVELOPING. RAP SOUNDINGS STILL SHOW
SOME ENHANCED RH AROUND 800MB...BUT THINKING ANY CLOUDS ASSOCIATED
WITH UPSLOPE FLW AND THIS MOISTURE WL QUICKLY DISSIPATE BY SUNSET.
GUIDANCE IS VERY COLD WITH SLK MAV/MET SHOWING READINGS OF
17/18...AND AROUND 29F FOR BTV. WL TREND A COUPLE DEGREES
HIGHER...BUT GIVEN VERY LOW SFC DWPTS AND LIGHT WINDS...THINKING
VALUES WL RANGE FROM THE UPPER 10S COLDER MTN VALLEYS/NEK TO M/U
20S ELSEWHERE.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
AS OF 320 PM EDT THURSDAY...MID/UPPER LVL RIDGE ACRS THE NE CONUS WL QUICKLY
SHIFT INTO EASTERN NEW ENGLAND BY 00Z SATURDAY...AS PROGRESSIVE
WESTERLY FLW ALOFT CONTS ACRS THE NORTHERN TIER OF THE UNITED
STATES. DEEP DRY LAYER AND STRONG SUBSIDENCE PER LATEST WATER
VAPOR TRENDS WL RESULT IN MOSTLY SUNNY SKIES ON FRIDAY
MORNING...BUT MID/UPPER LVL RH INCREASES AFT 18Z FROM SW TO NE.
BEST 850 TO 700MB OMEGA FIELDS AND ASSOCIATED RIBBON OF 850 TO
500MB RH >80% ARRIVES AFT 00Z SAT...SO WL KEEP FRIDAY DRY ATTM.
PROGGED 85H TEMPS RANGE FROM 0C NEK TO 4C SOUTHWEST
SLV...RESULTING IN TEMPS RANGING FROM THE L/M 50S NEK/MTNS TO L60S
SLV AND WARMER/UHI AREAS OF THE CPV.

FRIDAY NIGHT INTO SATURDAY...850 TO 500MB RH QUICKLY OVERSPREADS THE
FA WITH MODEST UVVS ASSOCIATED WITH 5H VORT AND DEVELOPMENT OF
MID/UPPER LVL TROF. STILL FEEL INITIAL 5H VORT AND MOISTURE WL
DISSIPATE ACRS OUR CWA ON FRIDAY NIGHT...WITH LEADING EDGE OF PRECIP
FALLING AS MOSTLY VIRGA...ESPECIALLY GIVEN VERY DRY LVLLS. BETTER
DYNAMICS AND DEEPER RH ARRIVES ASSOCIATED WITH CLOSED 5H/7H
CIRCULATION BTWN 06Z-12Z SATURDAY...WITH A BAND OF LIGHT TO MODERATE
RAIN ANTICIPATED. HAVE NOTED POCKETS OF COOLER PROGGED 85H TEMPS <0C
ACRS CENTRAL/NORTHERN VT/NEK ON SATURDAY MORNING...WHICH COULD
RESULT IN SOME WET SNOW IN THE MTN SUMMITS. COLD POOL ALOFT
ASSOCIATED WITH CLOSED SYSTEM MOVES DIRECTLY OVERHEAD ON
SATURDAY...WITH COOLING PROFILES ALOFT ANTICIPATED. THIS COMBINED
WITH SOME LIMITED SFC HEATING WL RESULT IN ADDITIONAL INSTABILITY
FOR MORE SCATTERED SHOWERS TO DEVELOP. BOTTOM LINE SAT WL BE COOL
AND DAMP WITH OCCASIONAL RAIN SHOWERS AND HIGH ELEVATION SNOW
SHOWERS LIKELY. TOTAL QPF WL RANGE BTWN 0.10 AND 0.50 OF AN INCH.
TEMPS WL RANGE FROM THE U30S/M40S NEK/MTNS TO M40S/L50S VALLEYS ON
SAT.

SATURDAY NIGHT...CLOSED MID/UPPER LVL CIRCULATION CONTS TO DEEPEN AS
SEVERAL EMBEDDED S/W`S INTERACT WITH THIS LARGE SYNOPTIC SCALE
SYSTEM. THIS WL SLOW OVERALL MOVEMENT OF SYSTEM DOWN WITH IT
BECOMING STATIONARY OFF THE NEW ENGLAND COASTLINE BY SAT NIGHT...AND
NUMEROUS RIBBONS OF MOISTURE ROTATING ACRS OUR CENTRAL/EASTERN CWA.
THIS COMBINED WITH DEVELOPING WEST TO NORTHWEST FLW WL RESULT IN
ADDITIONAL SHOWERS. GIVEN THE DEEPENING COLD POOL ALOFT AND
ASSOCIATED COOLING OF LLVL THERMAL PROFILES...THINKING SNOW LEVELS
WL DROP TO AROUND 2000 FT BY SUNDAY MORNING. HOWEVER...ACCUMULATIONS
SHOULD BE LIGHT. TEMPS WITH CLOUDS/WIND AND PRECIP WL HOLD MAINLY IN
THE 30S TO NEAR 40F...FAIRLY UNIFORMED ACRS OUR REGION.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 407 AM EDT THURSDAY...ECMWF AND GFS MODELS SHOW A CLOSED
UPPER LOW WILL BE OVER THE REGION SATURDAY NIGHT...SO WILL
CONTINUE WITH A CHANCE OF SHOWERS. THE CLOSED UPPER LOW WILL MOVE
EAST OF THE REGION BY SUNDAY...BUT THE FORECAST AREA WILL STILL
BE UNDER CYCLONIC FLOW...SO HAVE SLIGHT TO CHANCE POPS FOR
SHOWERS IN THE FORECAST FOR SUNDAY. EXPECTING MAINLY DRY
CONDITIONS SUNDAY NIGHT WITH JUST SOME SLIGHT CHANCE POPS FOR
SHOWERS OVER NORTHEAST VERMONT. A MAINLY DRY DAY ON MONDAY AS A
RIDGE OF HIGH PRESSURE BUILDS SOUTH FROM CANADA AND REMAINS OVER
THE REGION THROUGH MONDAY NIGHT.

ECMWF AND GFS MODELS SHOWING SOME MAJOR DIFFERENCES FOR THE
TUESDAY AND WEDNESDAY FORECAST. THUS...FORECASTER CONFIDENCE IS
LOW. ECMWF MODEL HAS A RIDGE OF HIGH PRESSURE AT THE SURFACE AND
ALOFT OVER THE REGION WITH A DRY FORECAST INDICATED FOR TUESDAY
AND WEDNESDAY... AS ECMWF MODEL SUGGESTING THE REGION WILL BE
UNDER AN OMEGA BLOCK WITH A CLOSED UPPER LOW OVER THE MID
MISSISSIPPI VALLEY WITH ANOTHER CLOSED UPPER LOW OVER THE
ATLANTIC SOUTH OF THE CANADIAN MARITIMES. HOWEVER...GFS MODEL
SHOWS A CLOSED UPPER LOW ALSO OVER THE MID MISSISSIPPI VALLEY
WITH THE OTHER CLOSED UPPER LOW MUCH FURTHER EAST IN THE ATLANTIC
THAN DEPICTED BY THE ECMWF MODEL. GFS MODEL BRINGS MOISTURE
NORTHEAST INTO THE REGION FROM THE SOUTHEASTERN U.S. TUESDAY AND
WEDNESDAY WITH A CHANCE OF SHOWERS. FOR NOW...WILL USE SUPER
BLEND POPS AND KEEP A CHANCE OF SHOWERS IN THE FORECAST FOR
TUESDAY AND WEDNESDAY...BUT GIVEN MODEL DIFFERENCES FORECASTER
CONFIDENCE IS LOW AT THIS TIME.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
THROUGH 18Z FRIDAY...VFR CONDITIONS ARE EXPECTED THROUGH THE
PERIOD. AS HIGH PRESSURE BUILDS INTO THE REGION THIS EVENING SCT-
BKN VFR DECK OVER NE VT WILL EVENTUALLY CLEAR OUT TO SKC AND GUSTY
NW WINDS ACROSS THE REGION WILL ABATE. EXPECT A PERIOD OF SKC ACROSS
THE ENTIRE REGION 00-06Z...THEN MID/HIGH CLOUDS AT 10-15KFT MOVE
IN FROM THE WEST IN ADVANCE OF OUR NEXT SYSTEM.

OUTLOOK 12Z FRIDAY THROUGH MONDAY...

18Z FRI THRU 00Z SAT...VFR WITH CIGS SLOWLY LOWERING TO NEAR 5KFT.

00Z SAT THRU 00Z MON...MIX OF MVFR/VFR WITH PERIODS OF SHOWERS
ASSOCIATED WITH UPPER LOW PASSAGE.

00Z MON THRU 00Z TUE...MVFR TRENDING TO VFR AS UPPER LOW PULLS
AWAY FROM THE REGION.

00Z TUE THRU 00Z WED...VFR UNDER HIGH PRESSURE.

&&

.FIRE WEATHER...
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AS OF 930 AM EDT THURSDAY...RED FLAG WARNING CONTINUES UNTIL 7 PM
THIS EVENING FOR PARTS OF CENTRAL/SOUTHERN VT AND EASTERN ESSEX
COUNTY NY.

FIRE WEATHER CONCERNS CONTINUE THIS AFTERNOON FOR ELEVATIONS BELOW
1500 FEET ACROSS THE SOUTHERN CHAMPLAIN VALLEY...AND PORTIONS OF
SOUTHERN VT...DUE TO THE COMBINATION OF THE RECENT DRY
SPELL...EXPECTED GUSTY WINDS...AND LOW MIN RH VALUES.

MOST THE CPV AND SOUTHERN VERMONT HAVE SEEN LESS THAN A QUARTER
INCH OF RAINFALL IN THE PAST FIVE DAYS...THIS HAS RESULTED IN
SIGNIFICANT DRYING OF THE FINE FUELS PER LOCAL FOREST CONTACTS
BELOW 1500 FEET...WHERE GREEN UP HAS NOT OCCURRED.
MEANWHILE...ABOVE 1500 FEET MOST OF THE FINE FUELS AND LEAF
LITTER IS COMPRESSED FROM RECENT SNOW PACK OR STILL WET. MOST OF
CENTRAL/NORTHERN VT MTNS AND NORTHERN NY HAVE RECEIVED MEASURABLE
PRECIP OVER THE PAST 2 TO 5 DAYS OR SNOW PACK IS STILL ON THE
GROUND ABOVE 2000 FEET...RESULTING IN LIMITED THREAT.

BREEZY WEST TO NORTHWEST WINDS OF 15 TO 25 MPH WITH GUSTS TO 35
MPH ARE EXPECTED ACRS THE HIGHER TRRN...PARTS OF THE CT RIVER
VALLEY...AND CHAMPLAIN VALLEY THIS AFTN.

IN ADDITION...MIN AFTN RH VALUES WL DROP BTWN 20% AND 30% ACRS
NRN NY...THE CPV AND SOUTHERN VT.

THESE CONDITIONS COMBINED WITH THE OVERALL DRYING OF
GRASSES...TWIGS...AND DEBRIS SUCH AS DEAD LEAVES FROM LAST FALL
WILL ALLOW ANY FIRES THAT DO OCCUR TO SPREAD QUICKLY...BURN
INTENSELY...AND BE DIFFICULT TO CONTAIN. PAY CLOSE ATTENTION TO
ANY OUTDOOR BURNING YOU MAY BE ATTEMPTING TODAY. MONITOR WEATHER
CONDITIONS...DO NOT LEAVE YOUR BRUSH OR DEBRIS PILE
UNATTENDED...AND HEED ANY ADVICE FROM YOUR LOCAL FIRE WARDEN.
-- End Changed Discussion --

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR VTZ009>012.
NY...RED FLAG WARNING UNTIL 7 PM EDT THIS EVENING FOR NYZ035.

&&

$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...WGH
AVIATION...LAHIFF
FIRE WEATHER...TABER/KGM