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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 280614
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
214 AM EDT MON JUL 28 2014

.SYNOPSIS...
DEVELOPING SURFACE LOW PRESSURE ACROSS NEW YORK WILL TRACK INTO
VERMONT ON MONDAY...RESULTING IN A WIDESPREAD MODERATE RAINFALL. A
FEW EMBEDDED THUNDERSTORMS WITH LOCALIZED GUSTY WINDS WILL BE
POSSIBLE OVER EASTERN VERMONT ON MONDAY AFTERNOON. TEMPERATURES WILL
BE SEVERAL DEGREES BELOW NORMAL TO START THE WORK WEEK...WITH SOME
SHOWERS LINGERING INTO TUESDAY AND WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 113 AM EDT SUNDAY...WITH LIGHT WINDS AND WET GROUND FROM
TODAY`S RAINFALL...I`VE ADDED PATCHY FOG INTO THE FORECAST THROUGH
THE NEXT COUPLE OF HOURS FOR A LARGE PORTION OF THE NORTH COUNTRY.
I`VE ALSO ADJUSTED POPS/WX AFTER MIDNIGHT TO BETTER SHOW TIMING OF
AREA OF MODERATE RAIN/EMBEDDED THUNDERSTORMS NOW IMPACTING SOUTH-
CENTRAL NEW YORK STATE. HI-RES CONVECTION-ALLOWING MODEL
REFLECTIVITY PROGS AND SIMPLE EXTRAPOLATION PUTS THE LEADING EDGE
OF THIS AREA OF MODERATE RAIN FROM THE SOUTHERN ST. LAWRENCE
VALLEY - ADIRONDACKS - SOUTHERN VT AREA AROUND 08-09Z. SHOWN HIGH
POPS (LIKELY TO CATEGORICAL) AND CONTINUING TO TAPER UPWARD
THROUGH 12Z. INSTABILITY IS LIMITED BUT THUNDER`S ALREADY ONGOING
ACROSS CENTRAL NEW YORK...IN ZONE OF MID-/UPPER-LEVEL DIFFLUENCE
AND IN THE POLEWARD EXIT REGION OF MID-LEVEL JET STREAK
APPROACHING WESTERN PA. THAT SYNOPTIC-SCALE LIFT WILL OFFSET THE
SCANT INSTABILITY AND KEEP THUNDER GOING AS BAND OF MODERATE RAIN
SPREADS NORTH. SO I`VE KEPT CHANCE THUNDER TIED TO THE
LIKELY/CATEGORICAL POPS.

TEMPS LOOK REASONABLY GOOD WITH ONLY ADJUSTMENT HERE TO MATCH
CURRENT OBSERVATIONS.

PREVIOUS NEAR-TERM DISCUSSION ISSUED AT 1001 PM EDT SUNDAY FOLLOWS...

AREAL COVERAGE OF SHOWERS CONTINUES TO DECREASE NOTICEABLY
TONIGHT. SHOULD ONLY BE SOME ISOLATED SHOWERS THROUGH THE EARLY
MORNING HOURS...THEN THE FOCUS TURNS TO THE LARGE AREA OF
PRECIPITATION TO OUR SOUTHWEST. POTENT STORM SYSTEM COMING OUT OF
THE EASTERN GREAT LAKES TONIGHT WILL CONTINUE TO ENHANCE
PRECIPITATION DEVELOPMENT ACROSS WESTERN AND CENTRAL NEW YORK
AFTER MIDNIGHT...AS WELL AS IN PENNSYLVANIA...WITH THE FLOW
GRADUALLY BACKING AND ALLOWING ALL OF IT TO MOVE UP INTO OUR AREA
TOWARD MORNING. GOING FORECAST HAS THIS COVERED WELL AND ONLY
TWEAKED GRIDS TO MATCH CURRENT CONDITIONS BEFORE TRANSITIONING TO
THE INCREASING PRECIPITATION CHANCES TOWARD MORNING.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 340 PM EDT SUNDAY...POTENT SYSTEM WL IMPACT OUR CWA ON
MONDAY AND MONDAY NIGHT...WITH A WIDESPREAD MODERATE TO LOCALIZED
HEAVY RAINFALL EVENT. IN ADDITION...STILL WATCHING FOR THE
POTENTIAL OF STRONG STORMS ACRS OUR EASTERN/SOUTHERN CWA ON MONDAY
AFTN...AS PART OF THIS AREA GETS INTO THE WARM SECTOR. TOTAL
RAINFALL AMOUNTS WL GENERAL BE BTWN 1 AND 2 INCHES BY TUESDAY WITH
THE HEAVIEST AMOUNTS FROM THE DACKS TO CPV TO NORTHERN/CENTRAL VT
MTNS. NOT ANTICIPATING ANY MAJOR HYDRO ISSUES...BUT COULD SEE SOME
MINOR POOR DRAINAGE URBAN FLOODING IN THE HIGHER RAINFALL RATES ON
MONDAY.

WATER VAPOR SHOWS POTENT 5H VORT ACRS THE WESTERN GREAT
LAKES...QUICKLY MOVING SE TWD THE OHIO VALLEY ATTM...WITH SOME
LIGHTNING ACTIVITY ALREADY NOTED UNDER THE 5H CIRCULATION. THIS
CONVECTIVE ACTIVITY AND UPSTREAM ACTION TODAY...MAKES FOR A TRICKY
SFC LOW TRACK HEADING INTO MONDAY...ALONG WITH THE EXACT PLACEMENT
OF A STRONG NW TO SE THERMAL BOUNDARY. AS VIGOROUS 5H VORT ROUNDS
MID/UPPER LVL TROF...SYSTEM WL BECOME NEGATIVELY TILTED BY 18Z
WEDS...WITH SFC LOW PRES TRACKING FROM NEAR KBGM AT 12Z MONDAY TO
NORTHERN VT BY 00Z TUES. THIS TRACK PLACES OUR WESTERN CWA ON THE
COOL SIDE...WHILE PARTS OF THE CENTRAL/EASTERN CWA WL BE IN THE WARM
SECTOR WITH THE POTENTIAL FOR CONVECTION ON MONDAY AFTN. THINKING
INITIAL SURGE OF MID WAA LIFT/MOISTURE WL DEVELOP ACRS
RUTLAND/WINDSOR COUNTIES AROUND 12Z MONDAY AND LIFT INTO
CENTRAL/NORTHERN VT 14Z...BEFORE BEING NORTH OF OUR CWA BY 16Z
MONDAY. THIS LIFT/MOISTURE WL RESULT IN A 2 TO 4 HOUR WINDOW OF
MODERATE RAINFALL WITH EMBEDDED STORMS. HOWEVER...AS SOME BREAKS
DEVELOP IN THE WARM SECTOR ON MONDAY AFTN...SFC INSTABILITY IS
EXPECTED TO INCREASE BTWN 800 AND 1200 J/KG...WITH 0 TO 6 KM SHEAR
AROUND 30 KNOTS. THINKING SCATTERED STORMS WL DEVELOP ACRS OUR
EXTREME EASTERN CWA...WITH A FEW STRONGER STORMS CAPABLE OF GUSTY
WINDS AND SMALL HAIL POSSIBLE....ESPECIALLY GIVEN THE VERY STRONG
DYNAMICS ALOFT. THE SYSTEM AND ASSOCIATED CONVECTION ON MONDAY WL BE
DRIVEN BY THE STRONG DYNAMICS AND NOT SO MUCH THE INSTABILITY. BOTH
THE GFS/NAM 850 TO 500MB RH PROGS SHOW A NICE WELL DEFINED DRY SLOT
DEVELOPING ACRS OUR EASTERN CWA AT 18Z MONDAY...WHILE A BAND OF DEEP
RH ASSOCIATED WITH BACKSIDE DEFORMATION EXTENDS FROM
NORTHERN/CENTRAL NY INTO NORTHERN VT. THIS MOISTURE COMBINED WITH
FAVORABLE NORTHWEST LOW LEVEL UPSLOPE FLOW AND ASSOCIATED LIFT FROM
THERMAL DRIVEN MID LVL TROWAL FEATURE WL HELP TO PRODUCE ADDITIONAL
MODERATE RAINFALL ACRS THE DACKS INTO THE CPV AND MOST OF
CENTRAL/NORTHERN VT ON MONDAY AFTN/EVENING. GIVEN THE TRACK OF THE
CLOSED 85H AND 7H CIRCULATIONS...AND SFC LOW...EXPECT BACKSIDE
DEFORMATION PRECIP TO LINGER OVERNIGHT MONDAY...BEFORE TAPERING OFF
ON TUES MORNING. THINKING TOTAL QPF WL RANGE BTWN 0.25 AN 0.75"
SLV/WESTERN DACKS TO 0.75 TO 1.75" EASTERN DACKS/CPV AND NORTHERN
VT....WITH AMOUNTS BTWN 0.50 AND 1.0" ACRS SOUTHERN/CENTRAL
VT...WITH SOME LOCALIZED HIGHER AMOUNTS AROUND 2.0" POSSIBLE DUE TO
CONVECTION AND TRRN. EXPECTING SOME SHARP RISES ON SMALLER
STREAMS/RIVERS...BUT GIVEN RECENT DRY SPELL NO MAJOR HYDRO ISSUES
ANTICIPATED ATTM. VERY INTERESTING TEMP PROFILE ON MONDAY WITH
NORTHERLY WINDS DOWN THE CPV/SLV AND LOW LEVEL CAA/CLOUDS...TEMPS WL
STRUGGLE IN THE UPPER 50S DACKS TO L/M60S CPV/SLV AND MID 70S LWR CT
RIVER VALLEY NEAR VSF. THE MTNS OF VT WL HOLD IN THE U50S TO LOWER
60S ON MONDAY WITH LOWER 70S POSSIBLE IN THE NEK VALLEYS.

TUESDAY-TUESDAY NIGHT...MID/UPPER LVL CLOSED CIRCULATION LIFTS INTO
EASTERN CANADA WITH CYCLONIC NW FLOW ACRS OUR CWA. BEST 850 TO 500MB
MOISTURE LIFTS NORTH OF OUR CWA BY 12Z TUES...BUT GIVEN AMOUNT OF
ENERGY IN THE FLOW ALOFT AND SOME SFC HEATING ON TUES AFTN...CANNOT
RULE OUT THE POTENTIAL FOR SOME SCATTERED SHOWERS TO DEVELOP IN THE
AFTN...ESPECIALLY WITH PLENTY OF LEFTOVER BL MOISTURE. THIS ACTIVITY
WL DECREASE BY TUES EVENING...WITH CHILLY NORTHWEST WINDS. TUES/TUES
NIGHT WL FEEL A BIT LIKE FALL WITH TEMPS ONLY WARMING INTO THE
U50S/L60S MTNS TO NEAR 70F WARMER VALLEYS...ASSOCIATED WITH PROGGED
85H TEMPS ONLY BTWN 6-8C. WINDS/CLOUDS AND PLENTY OF LEFTOVER BL RH
WL KEEP TEMPS FROM COMPLETELY BOTTOMING OUT ON TUES NIGHT...THINKING
MAINLY 40S MTNS TO 50S VALLEYS.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 315 PM EDT SUNDAY...MODELS REMAIN IN GOOD AGREEMENT INDICATING
DEEP LARGE SCALE TROUGH OVER THE EASTERN CONUS WITH RIDGE OVER THE
INTER-MOUNTAIN WEST THROUGH MUCH OF THE PERIOD...THOUGH TROUGH
WEAKENS LATER IN THE PERIOD WITH SLOWLY RISING HEIGHTS.

DESPITE THE PRESENCE OF LARGE UPPER TROUGH OVER THE REGION...EXPECT
MUCH OF THE TIME TO BE DRY. SHORTWAVES MOVING THROUGH THE MEAN TROUGH
DIFFICULT TO TIME THIS FAR OUT...BUT LATEST GUIDANCE SUGGESTS
STRONGEST DISTURBANCE WILL MOVE ACROSS THE AREA THURSDAY.
OTHERWISE...CHANCES FOR PRECIPITATION LARGELY DIURNALLY
DRIVEN...WITH BEST CHANCES DURING THE AFTERNOON HOURS AND MAINLY
DRY CONDITIONS ANTICIPATED EACH NIGHT AND EARLY MORNING.

BELOW NORMAL TEMPS EXPECTED THROUGH MIDWEEK. 850 MB TEMPS PROGGED TO
TO BE AROUND 10-11C WED/THU THEN MODERATE TO 12-13C BY THE WEEKEND.
WITH PARTIAL SUN...THIS SUPPORTS VALLEY HIGHS IN THE MID TO UPPER
70S WED/THU AND AROUND 80 FOR THE REST OF THE PERIOD. EXPECT MINS IN
THE 50S TO LOWER 60S.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
THROUGH 06Z TUESDAY...TRENDING MVFR LOCALLY IFR INITIALLY IN BR/FG
THEN IN MODERATE TO HEAVY RAIN WITH EMBEDDED THUNDERSTORMS AFTER
10-12Z AS LOW PRESSURE TRACKS EASTWARD ACROSS NY THEN NORTHEAST
ALONG A FRONTAL SYSTEM THROUGH CENTRAL NEW ENGLAND TO WESTERN
ME/SOUTHERN QUEBEC BY 06Z TUE.

PATCHY FG/BR GIVE WAY TO RAIN...MODERATE TO HEAVY AT TIMES WITH
EMBEDDED THUNDER BEGINNING 10-12Z FROM SW TO NE. EXPECT
CONDITIONS TO LOWER TO MVFR AREA-WIDE WITH POSSIBLE IFR AT TIMES.
THUNDER POSSIBLE FROM KSLK EASTWARD AND HAVE INDICATED WITH VCTS.

LIGHT WINDS EARLY TODAY GRADUALLY BECOMING NORTHERLY 10 TO 15 KTS
TODAY AT BTV/PBG. WINDS NE BECOMING N AT MSS/SLK. AT RUT/MPV
LIGHT E/SE WINDS WILL BECOME W/NW LATER TODAY.

OUTLOOK 00Z MONDAY THROUGH FRIDAY...

00Z TUE - 12Z TUE...PERIODS OF MVFR IN RAIN TAPERING OFF. LOCAL
IFR POSSIBLE IN HEAVIER RAIN.

12Z TUE - 12Z THU...TRENDING VFR. POSSIBLE IFR/LOWER VISIBILITY IN
OVERNIGHT FOG/MIST MPV AND SLK.

12Z THU ONWARD...MAINLY VFR ALTHOUGH BRIEF PERIODS OF MVFR
POSSIBLE IN SCATTERED SHOWERS.
-- End Changed Discussion --

&&

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

&&

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