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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 230037
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
837 PM EDT WED MAY 22 2013

.SYNOPSIS...
FRONTAL BOUNDARY WILL CONTINUE TO LIFT NORTHWARD ACROSS THE
REGION OVERNIGHT. SCATTERED TO ISOLATED THUNDERSTORMS ARE
EXPECTED THROUGH 10PM...SOME STORMS MAY BE SEVERE. A SLOW-MOVING
COLD FRONT WILL THEN APPROACH FROM THE EASTERN GREAT LAKES REGION
BRINGING ADDITIONAL WIDESPREAD RAINFALL AND EMBEDDED
THUNDERSTORMS DURING THURSDAY AND THURSDAY NIGHT. WHILE IT WON/T
BE RAINING CONTINUOUSLY...PERIODS OF BRIEFLY HEAVY RAIN
ASSOCIATED WITH THE SHOWERS AND THUNDERSTORMS WILL GENERALLY
BRING AN ADDITIONAL 1 TO 2 INCHES OF RAIN ACROSS THE NORTH
COUNTRY THROUGH THURSDAY NIGHT. SOME MINOR FLOODING WILL BE
POSSIBLE...MAINLY THURSDAY INTO THURSDAY NIGHT WITH THE MOST
WIDESPREAD RAINFALL.

&&

.NEAR TERM /UNTIL 8 AM THURSDAY MORNING/...
-- Changed Discussion --
AS OF 817 PM EDT WEDNESDAY...SEVERE THUNDERSTORM WATCH REMAINS IN
EFFECT UNTIL 10PM. LATEST RADAR INDICATES THAT THE STRONG TO SEVERE
STORMS WITH LOCALLY HEAVY AMOUNTS OF RAINFALL WHICH AFFECTED MUCH
OF THE AREA ARE DECREASING IN BOTH COVERAGE AND INTENSITY AS
ATMOSPHERE BEGINS TO STABILIZE. STILL EXPECTING SOME SHOWERS WITH
POSSIBLE THUNDER OVERNIGHT HOWEVER AS GOING FORECAST INDICATES. HAVE
MADE SOME MINOR ADJUSTMENTS TO HOURLY GRIDS FOR THIS EVENING TO
ACCOUNT FOR LATEST DATA...BUT NO CHANGES TO OVERALL FORECAST FOR
THE OVERNIGHT.

PREVIOUS DISCUSSION...
REGION CONTINUES TO BE UNDER SEVERE THUNDERSTORM WATCH
THRU 10PM. LARGE HAIL...DAMAGING WINDS...AND VERY HEAVY RAIN ARE
POSSIBLE IN ANY THUNDERSTORMS. FRONT ACROSS THE AREA LIFTS
NORTHWARD OVERNIGHT AND SHOWERS AND THUNDERSTORMS END BY ABOUT
11PM. THEN SYNOPTIC FEATURE BRINGS RENEWED CHANCE OF SHOWERS WITH
EMBEDDED THUNDERSTORMS DURING THE OVERNIGHT HOURS FROM WEST TO
EAST ACROSS THE AREA. DEEP-LAYER SWLY FLOW AND WARM ADVECTION
CONTINUES. SEVERE PARAMETERS LOOK LESS FAVORABLE
OVERNIGHT...THEREFORE HAVE DROPPED ENHANCED WORDING. LOWS WILL BE
ON THE WARM SIDE TONIGHT WITH 60S DEWPOINTS IN PLACE ALONG WITH
CLOUDS AND S-SW WINDS ALL NIGHT. LOW TEMPS WILL MAINLY BE IN THE
UPR 50S TO LOWER 60S.
-- End Changed Discussion --

&&

.SHORT TERM /8 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 350 PM EDT WEDNESDAY...THURSDAY WILL PRODUCE OUR MOST
WIDESPREAD RAINFALL AS COLD FRONT AND ASSOCIATED POSITIVE TILT
500MB TROUGH BEGINS TO SHIFT SLOWLY SEWD ACROSS THE FORECAST
AREA. MOIST AND MARGINALLY UNSTABLE AIR MASS WILL SUPPORT SEVERAL
BANDS OF SLOW MOVING CONVECTION ALONG/IN ADVANCE OF THE COLD
FRONT. GIVEN THE SETUP...MOST OF THE NWP QPF LOOKED ON THE LOW
SIDE GIVEN EVOLUTION AND MOIST AIR MASS IN PLACE. TRENDED CLOSER
TO HIGHER ECMWF QPF WITH WIDESPREAD 1+" RAINFALL AMTS ACROSS THE
CWA. SOME OF THIS HEAVY RAIN CONTINUES INTO THURSDAY
NIGHT...ESPECIALLY CENTRAL AND ERN VT. CAN/T RULE OUT LOCALIZED
2" RAINFALL AMTS BEFORE THINGS LIGHTEN UP EARLY FRIDAY. SOME
MINOR FLOODING IS POSSIBLE...REFER TO HYDRO SECTION BELOW. HIGHS
THURSDAY GENERALLY IN THE MID 70S. EPISODES OF SHOWERS/TSTMS
EXPECTED UNDER CLOUDY SKIES. FRIDAY...LIKELY POPS FOR RAIN
SHOWERS IN THE MORNING...THEN SLOW/GRADUAL DRYING FROM NW-SE
ACROSS THE REGION. SHOULD SEE SOME PARTIAL SUNSHINE LATE IN THE
DAY FROM THE CHAMPLAIN VALLEY WWD. COOLER TEMPS WITH HIGHS IN THE
LOW-MID 60S.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 255 PM EDT WEDNESDAY...STILL NOT A VERY CLEAR CUT FORECAST
FOR THE HOLIDAY WEEKEND, BUT IT`S LOOKING INCREASINGLY LIKELY
THAT SATURDAY WILL FEATURE SOME RAIN -- AND PERHAPS EVEN INTO
SUNDAY FOR PARTS OF THE AREA THANKS TO A SLOW MOVING UPPER TROUGH
AND ASSOCIATED SURFACE LOW PRESSURE. MEMORIAL DAY AND AFTER DOES
LOOK DRY WITH WARMING TEMPERATURES. DAILY SPECIFICS BELOW:

SATURDAY: DECENT AMOUNT OF VARIABILITY IN THE MODELS. NAM PUSHES
THE TROUGH AND LOW PRESSURE OUT THE QUICKEST AND WOULD FEATURE A
PRETTY DRY DAY, WHILE 12Z GFS AND 00Z EURO ARE PRETTY SIMILAR
FEATURING A "BATTEN DOWN THE HATCHES" WET DAY AS THEY HOLD BACK
THE TROF AND LOW THE LONGEST. THIS SOLUTION WOULD FEATURE A SLUG
OF HEAVY RAIN, PROBABLY ACROSS VERMONT -- AND THIS COULD RESULT
IN FLOODING ISSUES. 00Z GFS ENSEMBLES ARE A BIT QUICKER, BUT
STILL FEATURE PRECIPITATION FOR THE DAY. GIVEN A BIG OMEGA BLOCK
EXPECTED TO FORM OVER THE ATLANTIC, THAT MEANS EVERYTHING WILL
SLOW DOWN. THUS FEEL THE FAST NAM NEEDS TO BE DISCARDED, BUT THE
GFS/EURO COMBO MIGHT BE A LITTLE SLOW. AT THE END OF MY THOUGHT
PROCESS THOUGH, FELT IT NECESSARY TO INCREASE POPS -- WITH THE
BEST CHANCE ACROSS VERMONT WHERE IT WILL BE CLOSER TO THE LOW OFF
THE COAST. ST LAWRENCE VALLEY SHOULD REMAIN DRY AND A LITTLE BIT
OF LIGHT RAIN COULD COME BACK TO THE `DACKS. WITH ALL THE CLOUDS
AND COLD AIR WITH THE ASSOCIATED TROUGH, TEMPERATURES WILL BE
WELL BELOW NORMAL, 50S IN THE VALLEYS AND 40S IN THE HIGHER
TERRAIN. GONNA BE A DAMP/DREARY DAY. ADDING TO THE MISERY WILL BE
SOME BREEZY CONDITIONS. NORTH/NORTHWEST WINDS SHOULD GUST UPWARDS
OF 25 MPH. COME SATURDAY NIGHT, COLDER AIR ALOFT COULD RESULT IN
A LITTLE BIT OF SNOW AT ELEVATIONS PRIMARILY ABOVE 2500FT.

SUNDAY: WILL BE A TRANSITION DAY. LOW PRESSURE WILL BE MOVING
TOWARD THE CANADIAN MARITIMES, BUT ENOUGH MOISTURE ROTATING BACK
SO THAT I EXPECT CLOUDS AND LIGHT PRECIPITATION TO CONTINUE,
ESPECIALLY ACROSS EASTERN SECTIONS. HAVE PLACED LOW CHANCE POPS
BACK TO THE CHAMPLAIN VALLEY WITH HIGHER IN EASTERN VERMONT. NEW
YORK SHOULD REMAIN DRY. BY LATE IN THE DAY, CLOUDS SHOULD BE
BREAKING UP FROM WEST TO EAST. WILL BE CHILLY AND CONTINUED
BREEZY. 850MB TEMPERATURES ALOFT WILL BE ON EITHER SIDE OF 0C.
EVEN IN PERFECTLY SUNNY/DRY CONDITIONS, THIS WOULD ONLY SUPPORT
VALLEY HIGHS ABOUT 60F. WITH CLOUDS AND CONTINUED NORTHERLY FLOW,
I SUSPECT LOW 50S WILL BE IT FOR LOWER ELEVATIONS AND 40S IN THE
HIGHER TERRAIN. AGAIN SUNDAY MORNING AT THE HIGHEST SUMMITS, I`M
EXPECTING A LITTLE BIT OF SNOW. MAYBE ACCUMULATING TO 1" OR SO ON
MANSFIELD BY MID-DAY.

MEMORIAL DAY: GETTING BETTER AND WILL BE THE BEST DAY FOR ALL
OUTDOOR ACTIVITIES. PERHAPS RESIDUAL CLOUDS EARLY ACROSS THE
EAST, BUT OTHERWISE MOSTLY SUNNY. STILL COOL ALOFT, BUT 850MB
TEMPERATURES UP TO ABOUT 4C, SUPPORTING SURFACE HIGHS ABOUT 10F
WARMER THAN SUNDAY. LOTS OF LOW-MID 60S AT LOWER ELEVATIONS AND
UPPER 50S AT HIGHER ELEVATIONS.

DO NEED TO NOTE THAT THE 12Z EURO IS JUST COMING IN, AND IT
SUGGESTS AN EVEN SLOWER MOVE OUT OF THE TROUGH AND UPPER LOW. IN
FACT, IF THAT MODEL FORECAST ENDS UP PERFECT, THEN EVEN MONDAY
WILL BE CLOUDY/COOL/SOME RAIN -- VERY MUCH LIKE SUNDAY.

TUESDAY/WEDNESDAY: RIDGING SLOWLY BUILDS IN, ALONG WITH WARMER
TEMPERATURES ALOFT. EACH DAY SHOULD FEATURE TEMPERATURES ABOUT 5
TO 7 WARMER THAN THE PREVIOUS ONE -- SO SHOULD BE SOME NICE DAYS
(AGAIN ASSUMING THINGS DONT COME TO A COMPLETE STANDSTILL AND
KEEP US SMACK IN THE MIDDLE OF THE TROUGH).

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
THROUGH 00Z FRIDAY...SCATTERED SHOWERS AND THUNDERSTORMS ACROSS
THE REGION THIS EVENING. VFR CONDITIONS WILL DETERIORATE TO MVFR
WITHIN SHOWERS AND LIFR/IFR IN ANY THUNDERSTORMS THIS EVENING.
AFTER 04Z...EXPECT SOME SHOWERS WITH EMBEDDED THUNDER. PLENTIFUL
LLVL MOISTURE WILL RESULT IN WIDESPREAD MVFR CIGS WITH AREAS OF
IFR OVERNIGHT. DURING THURSDAY...COVERAGE OF SHOWERS AND THUNDERSTORMS
INCREASES BY AFTERNOON WITH APPROACH OF COLD FRONT. PREVAILING
MVFR DURING THURSDAY AFTERNOON...WITH LOCAL IFR AND POSSIBLE WIND
GUSTS 40 KTS IN THUNDERSTORMS.

OUTLOOK 00Z FRIDAY THROUGH MONDAY...UNSETTLED WX WITH OCCASIONAL
SHOWERS/STORMS WILL CONTINUE THURSDAY NIGHT INTO FRIDAY ACROSS OUR
TAF SITES. THE STRONGER SHOWERS/STORMS THURSDAY EVENING
ASSOCIATED WITH A SFC COLD FRONT WILL PRODUCE MVFR CONDITIONS...WITH
BRIEF PERIODS OF IFR LIKELY. ALSO...ANY STORMS WILL HAVE THE
POTENTIAL TO PRODUCE GUSTY SFC WINDS UP TO 40 MPH. AREAS OF FOG
AND LOW CLOUDS ARE POSSIBLE THURSDAY NIGHT...WITH SOME LOCALIZED
IFR/LIFR LIKELY. SCATTERED SHOWERS MAY LINGER INTO SATURDAY/SUNDAY
WITH MVFR...BEFORE HIGH PRESSURE SLOWLY BUILDS INTO THE REGION BY
EARLY NEXT WEEK. GUSTY NORTHWEST WINDS ARE POSSIBLE OVER THE
WEEKEND...WITH AREAS OF LLVL TURBULENCE.
-- End Changed Discussion --

&&

.HYDROLOGY...
350 PM WEDNESDAY...WIDESPREAD 1.0" TO 1.5" RAINFALL (WITH LOCALLY
HIGHER AMTS) HAS OCCURRED ACROSS THE NORTH COUNTRY DURING THE
PAST 24-30 HOURS ASSOCIATED WITH SEVERAL EPISODES OF HEAVY
SHOWERS AND TSTMS. AN ADDITIONAL 1-2" RAINFALL IS FORECAST
BETWEEN LATE AFTN/EVENING SHOWERS AND TSTMS AND THE MORE
WIDESPREAD RAIN AND EMBEDDED TSTMS ON THURSDAY. WHILE ANTECEDENT
SOIL CONDITIONS HAVE BEEN DRY...AND VEGETATION IS FULLY
ACTIVE...THE ADDITIONAL RAINFALL WILL EVENTUALLY BRING THE
POTENTIAL FOR STREET/POOR DRAINAGE FLOODING. ASSOCIATED MINOR
FLOODING WOULD MOST LIKELY OCCUR DURING THE DAY THURSDAY AND INTO
THURSDAY NIGHT. MAIN-STEM RIVER FLOODING IS NOT FORECAST...BUT
MAY NEED TO WATCH SOME OF THE SMALLER RIVERS AND STREAMS THAT
COULD LOCALLY EXCEED BANKFUL LATER THURSDAY AND THURSDAY NIGHT.

&&

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

&&

$$
SYNOPSIS...BANACOS/NEILES
NEAR TERM...RJS/NEILES
SHORT TERM...BANACOS/NEILES
LONG TERM...NASH
AVIATION...KGM
HYDROLOGY...