-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 172319
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
719 PM EDT FRI MAY 17 2013

.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL CONTINUE TO BUILD DOWN FROM
EASTERN CANADA AND PERSIST OVER NORTHERN NEW ENGLAND THROUGH MUCH OF
THE WEEKEND. LOOK FOR MORE DRY WEATHER WITH JUST A SLIGHT CHANCE OF
SHOWERS SUNDAY AFTERNOON AND NIGHT. A GRADUAL WARMING TREND IS ALSO
EXPECTED FOR THE WEEKEND.

&&

.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
-- Changed Discussion --
AS OF 713 PM EDT FRIDAY...GOING FORECAST IN GOOD SHAPE. SURFACE
RIDGE BUILDING INTO THE REGION WILL LEAD TO THE SLACKENING OF
WINDS AND GRADUAL DISSIPATION OF ANY CLOUDS OVERNIGHT. MAY SEE A
STRAY SPRINKLE FOR THE NEXT HOUR OR SO OVER THE HIGHER ELEVATIONS
OF THE NORTHERN GREENS. OTHERWISE...LOW TEMPERATURES STILL
EXPECTED TO FALL INTO THE 30-40 DEGREE RANGE...WITH A FEW UPPER
20S IN THE COLDEST AREAS OF THE ADIRONDACKS. THUS PATCHY FROST IS
STILL A CONCERN FOR SOME LOCATIONS WHERE THE GROWING SEASON HAS
ALREADY STARTED.

PREVIOUS DISCUSSION FROM 317 PM EDT FRIDAY...
NORTHWEST FLOW ALOFT CONTINUES OVER THE AREA THIS AFTERNOON AND
WILL PERSIST THROUGH THE NIGHT. STRATOCUMULUS WILL DISSIPATE AFTER
SUNSET AS LOW LEVEL LAPSE RATES STABILIZE. THE WINDS WILL TAPER
OFF AS WELL. THERE HAVE BEEN A FEW SHOWERS NORTH OF MONTREAL THIS
AFTERNOON...BUT DO NOT EXPECT THEM TO MAKE IT THIS FAR SOUTH. THUS
WILL LEAVE THE FORECAST DRY FOR THE REST OF THIS AFTERNOON AND
NIGHT. ONCE SKIES CLEAR AND WINDS TAPER OFF...LOOKING AT THE
DEVELOPMENT OF FROST ACROSS MOST AREAS WITH THE EXCEPTION OF THE
SAINT LAWRENCE VALLEY. SINCE GROWING SEASON HAS STARTED ACROSS THE
SAINT LAWRENCE VALLEY AND NORTH CENTRAL/SOUTH CENTRAL
VERMONT...WILL INCLUDE FROST IN THE FORECAST AND HIGHLIGHT IN THE
HAZARDOUS WEATHER OUTLOOK WITH READINGS DROPPING INTO THE MID 30S.
-- End Changed Discussion --

&&

.SHORT TERM /8 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 317 PM EDT FRIDAY...LOW LEVEL FLOW BEGINS TO GRADUALLY BACK TO
THE WEST ON SATURDAY AND EVENTUALLY THE SOUTHWEST ON SUNDAY. THIS
WILL ALLOW A WARMING TREND TO BEGIN WITH HIGH TEMPERATURES ABOUT 5
TO 10 DEGREES WARMER THAN TODAY. DRY AIR MASS IN PLACE WILL RESULT
IN NO PRECIPITATION ON SATURDAY AND MOST OF SUNDAY. THERE IS A
LITTLE RETURN FLOW ON SUNDAY...BUT NO FORCING AND INSTABILITY IS A
BIT WEAK. HAVE KEPT A SLIGHT CHANCE GOING OVER PARTS OF OUR
SOUTHERN AND WESTERN AREAS CLOSER TO ANY SORT OF INSTABILITY
SUNDAY AFTERNOON AND EVENING.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 345 PM EDT FRIDAY...OVERALL A MORE ACTIVE PATTERN
ANTICIPATED FOR DAYS 4 THRU 7 WITH SEVERAL CHANCES FOR SHOWERS AND
MAYBE SOME THUNDERSTORMS. STILL ANTICIPATING A COMPLEX MID/UPPER
LVL PATTERN ACRS THE NE/EASTERN CONUS WITH TROF ACRS EASTERN
CANADA...DEVELOPING RIDGE OVER THE SE...AND CLOSED 5H/7H
CIRCULATION ACRS THE PLAINS. THIS WL CREATE A FAST WESTERLY FLW
ACRS OUR CWA...WITH EMBEDDED VORTS EJECTING FROM CENTRAL PLAINS
SYSTEM EVERY COUPLE OF DAYS. THIS VORTS WL RIDE ALONG A SFC
BOUNDARY PROGGED TO BE FROM THE GREAT LAKES/OHIO VALLEY INTO
SNE/NE CONUS THRU THE PERIOD. THE EXACT POSITION OF THIS BOUNDARY
WL PLAY A MAJOR ROLE IN TEMPS/INSTABILITY/POPS AND PLACEMENT OF
HEAVIEST QPF. GFS/ECMWF CONT TO SHOW DIFFERENT SOLUTIONS WITH
REGARDS TO BOUNDARY AND ASSOCIATED SHARP THERMAL GRADIENT. GIVEN
THE UNCERTAINTY AND POTENTIAL FOR SEVERAL WEAK AREAS OF LOW PRES
TO DEVELOP ALONG THE FRONT...WL CONT TO MENTION CHC POPS FOR TUES
THRU THURS. THE HIGHEST CHC POPS WOULD BE TUES...AS COLD FRNT
DROPS SOUTH...THEN AGAIN ON THURS. STILL SOME QUESTION WITH
REGARDS TO AMOUNT OF SFC HEATING...ESPECIALLY WITH EXPECTED CLOUD
COVER...BUT SOME INSTABILITY WL BE PRESENT ALONG AND SOUTH OF THE
BOUNDARY ON TUES...WITH CAPE VALUES APPROACHING 1000 J/KG. HAVE
MENTION SCHC FOR THUNDER. OTHERWISE...TIGHT THERMAL GRADIENT FROM
MONDAY THRU THURS ACRS OUR CWA...WL MAKE TEMP FCST TRICKY. IF WE
PUSH WELL INTO THE WARM SECTOR...WHICH IS POSSIBLE ON
MONDAY/TUES...TEMPS AHEAD OF SFC COLD FRNT COULD BE WELL INTO THE
80S...GIVEN PROGGED 85H TEMPS NEAR 14C. BUT IF BOUNDARY GETS HUNG
UP...AND MORE CLOUDS/PRECIP LINGER...THAN HIGHS WOULD ONLY BE IN
THE 60S. HAVE TRENDED SLIGHTLY ABOVE NORMAL WITH HIGHS MAINLY IN THE
70S AND LOWS IN THE U40S TO NEAR 60F THRU THE PERIOD.

&&

.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...VFR CONDITIONS THRU 18Z SATURDAY WL PREVAIL
AT OUR TAF SITES. SFC ANALYSIS PLACES RIDGE AXIS ACRS WESTERN NY
WITH MOVEMENT TWD OUR REGION. SOME SFC HEATING CLOUDS HAVE
DEVELOPED ACRS THE MTNS...WHICH WL QUICKLY DISSIPATE THIS
EVENING...WITH NW WINDS 10 TO 15 KNOTS...BECOMING LIGHT AND TRRN
DRIVEN TONIGHT. SLK WL REACH 2 TO 3 DEGREES BLW CROSS OVER TEMP
TONIGHT...BUT LLVLS ARE VERY DRY...THEREFORE NOT THINKING ANY
FOG/BR ATTM. SATURDAY...EXPECT VFR CONDITIONS WITH SOME HIGH
CLOUDS TWD AFTN.

OUTLOOK 18Z SATURDAY THROUGH TUESDAY...
VFR FROM 18Z THRU TUESDAY...WITH CHCS INCREASING FOR SHOWERS BY
EARLY NEXT WEEK. THIS COULD RESULT IN A PERIOD OF MVFR
CIGS/VIS...ESPECIALLY ON TUES IN THE HEAVIER SHOWERS. IN
ADDITION...A SPRINKLE ASSOCIATED WITH A WARM FRNT WL BE POSSIBLE
LATE SUNDAY INTO EARLY MONDAY.

&&

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

&&

$$
SYNOPSIS...EVENSON
NEAR TERM...EVENSON/MUCCILLI
SHORT TERM...EVENSON
LONG TERM...TABER
AVIATION...TABER