372
FXUS61 KBTV 161506
AFDBTV
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
1006 AM EST MON DEC 16 2024
SYNOPSIS
RELATIVELY QUIET WEATHER CONDITIONS ARE EXPECTED TODAY AS LIGHT
SNOW COMES TO A CLOSE TODAY. THERE IS A CHANCE FOR SOME DRIZZLE
THIS EVENING ACROSS PARTS OF EASTERN VERMONT. BE AWARE OF
TEMPERATURES FOR THE EVENING COMMUTE AS DRIZZLE SHIFTS INTO THE
REGION. STRONG SOUTHERLY GUSTS WILL DEVELOP TONIGHT OVER THE
NORTHERN SLOPES OF THE ADIRONDACKS AND IN THE NORTHERN CHAMPLAIN
VALLEY, WHERE GUSTS OF 35 TO 45 MPH ARE EXPECTED. PERIODS OF
RAIN SHOWERS ON TUESDAY WILL TRANSITION TO LAKE EFFECT LATER IN
THE EVENING. SEVERAL FAST MOVING WEATHER DISTURBANCES WILL
TRAVERSE THE REGION THROUGHOUT THE WEEK WITH ADDITIONAL RAIN AND
SNOW CHANCES.
NEAR TERM /THROUGH TUESDAY/
AS OF 959 AM EST MONDAY...QUICK UPDATE TO ISSUE WIND ADVISORY
FOR NORTHERN DACKS INTO THE CPV AND PARTS OF THE NORTHERN GREENS
FROM 7 PM THIS EVENING TO 4 PM TUES. EXPECTING TWO PERIODS OF WINDS
GUSTS OF 45 TO 50 MPH TO OCCUR. FIRST IS TONIGHT FROM 9 PM TO 2
AM FROM THE SOUTHWEST, FOLLOWED BY THE SECOND FROM A WESTERLY
DIRECTION BTWN 8 AM AND 2 PM ON TUES. LATEST GUIDANCE CONTINUES
TO SUPPORT A ROBUST 850MB JET OF 55 TO 65 KNOTS MOVING ACRS THE
REGION TONIGHT, STILL SOME QUESTION WITH REGARDS TO MIXING, BUT
GIVEN 925MB WINDS OF 55 TO 60 KNOTS ALONG THE NORTHERN SLOPES OF
THE DACKS FEEL LOCALIZED GUSTS TO 50 MPH IS HIGHLY PROBABLY. AS
MIXING IMPROVES ON TUES FROM CAA, FEEL ADDITIONAL GUSTY
WESTERLY WINDS WILL DEVELOP ON EASTERN SIDE OF THE DACKS AND
EAST SIDE OF THE NORTHERN GREENS. HAVE NOTED THE 12Z GUIDANCE IS
STILL INDICATING LOW LEVEL COLD AIR REMAINING TRAPPED EAST OF
THE GREEN THIS EVENING, SUPPORTING A PERIOD OF PATCHY FREEZING
DRIZZLE. IF CONFIDENCE INCREASES IN BL TEMPS AT OR BELOW 0C, WE
PLAN TO ISSUE SPS TO HANDLE SLICK SPOTS DURING EVENING COMMUTE.
PREVIOUS DISCUSSION BELOW:
THE TRICKY PART THIS EVENING IS HOW MUCH COOL AIR REMAINS LOCKED IN
EASTERN VERMONT AS MARITIME MOISTURE TRACKS NORTHWARDS. TEMPERATURES
COULD BE HOVERING AROUND THE FREEZING MARK LATER THIS EVENING, AND
DEPENDING ON HOW EARLY LOW-LEVEL MOISTURE ARRIVES, THERE COULD BE A
FEW POCKETS OF FREEZING DRIZZLE. FOR NOW, WILL CONTINUE TO MONITOR
TRENDS AND HOW WARM TEMPERATURES GET.
OVERNIGHT, A STRONG 55-65 KNOT LOW-LEVEL JET WILL DEVELOP ACROSS THE
REGION. THIS SHOULD PROMOTE INCREASING GUSTS OVERNIGHT.
PROBABILISTIC GUIDANCE FROM THE HREF IS SURPRISINGLY AGGRESSIVE,
INDICATING 70-100 PERCENT PROBABILITIES OF GUSTS GREATER THAN 50
MPH. HOWEVER, FORECAST SOUNDINGS ARE EITHER NEUTRAL OR FEATURE AN
INVERSION BELOW THE CORE OF STRONGEST WINDS THAT IS BELOW RIDGE
TOPS. ANALYZING CROSS SECTIONS OF DOWNSLOPE REGIONS DOES NOT APPEAR
TO MATCH SIGNALS FOR MOUNTAIN WAVE BREAKING. CROSS SECTIONS
HIGHLIGHT THE DOWNSLOPE WINDS WELL, BUT DEEP MOISTURE IS ALREADY IN
PLACE WHERE WE ARE USUALLY LOOKING FOR DRY SUBSIDENCE, AND
PRECIPITATION LOOKS TO ARRIVE WITH THE JET FORMATION. THE
FORECAST WILL SOMEWHAT RELY ON HAVING THE JET DEVELOP AS WELL.
A DELAY IN ITS DEVELOPMENT BEFORE IT LIFTS NORTH COULD LEAVE US
LESS WINDY AS WELL. THE SHORT OF IT IS THAT THERE ARE SEVERAL
FORECAST INDICATORS THAT SUGGEST KEEPING THINGS FROM GUSTING TOO
STRONGLY. PRESSURE GRADIENTS WILL ALLOW FOR STRONG CHANNELING
IN THE CHAMPLAIN VALLEY WITH SOME DOWNSLOPE ENHANCEMENT THAT
PLACES AN EXPECTED FORECAST OF 35 TO 45 MPH GUSTS IN THE
NORTHERN CHAMPLAIN VALLEY AND NORTHERN SLOPES OF THE
ADIRONDACKS. THERE COULD BE A LOCALIZED GUST TO 50 AT COMMON
TROUBLE SPOTS LIKE MALONE, ELLENBURG, AND THE MILTON SANDBAR.
WILL GIVE ANOTHER CYCLE TO ASSESS WHETHER HEADLINES ARE NEEDED.
ANY INCREASE IN LOW-LEVEL INSTABILITY OR LOWERING OF WHERE THE
STRONGEST WINDS ARE LOCATED WOULD NECESSITATE HEADLINES.
THE PRECIPITATION ASPECT OF THIS REMAINS UNCHANGED. A BRIEF
CONVERGENCE OF FAVORABLE INGREDIENTS FOR PRECIPITATION SHOULD
PRODUCE 0.10-0.50" WITH LOCALLY MORE OR LESS DEPENDING ON TERRAIN.
RAIN IS GOING TO RACE EAST, AND WILL BE OUT OF HERE BY TUESDAY
MORNING. AFTERWARDS, WE WILL AGAIN NEED TO WATCH GUSTS. RISING
HEIGHTS BEHIND THE FRONT AND THE PRESENCE OF 50 KNOT WINDS AROUND
3500-4500 FEET WILL BEAR SOME WATCHING. THERE COULD BE ANOTHER
WINDOW FOR STRONG WINDS BEFORE THINGS SETTLE TUESDAY AFTERNOON. SOME
LAKE EFFECT SHOWERS WILL DEVELOP, BUT A LACK OF COOL AIR WILL
KEEP LAPSE RATES RELATIVELY LOW. TEMPERATURES WILL STILL BE IN
THE 40S FOR MOST ON TUESDAY, BUT NOT FEELING PLEASANT WITH GUSTY
SOUTHWEST WINDS.
SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/
AS OF 313 AM EST MONDAY...WE'VE GOT A BRIEF BREAK IN THE ACTIVE
WEATHER PATTERN TUESDAY NIGHT AND WEDNESDAY AS THE FRONTAL SYSTEM
WILL QUICKLY BE RACING EASTWARD. DIMINISHING WINDS AND RAIN CHANCES
WILL BE THE HIGHLIGHT OF THE TUESDAY NIGHT PERIOD. SLIGHTLY COOLER
TEMPERATURES ARE EXPECTED ON WEDNESDAY WITH HIGHS IN THE UPPER 30S
TO LOWER 40S DUE TO A COMBINATION OF WEAK COLD ADVECTION AND A
PLETHORA OF CLOUD COVER. WE WILL BEGIN TO SEE PRECIPITATION CHANCES
INCREASE CLOSE TO SUNSET ON WEDNESDAY ACROSS NORTHERN NEW YORK AS A
MORE AMPLIFIED UPPER LEVEL TROUGH AND STRONGER COLD FRONT DEVELOP
ACROSS THE REGION. MORE ON THIS IN THE LONG TERM SECTIONS BELOW.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/
AS OF 313 AM EST MONDAY...A FAST MOVING STORM SYSTEM IS EXPECTED TO
BRING A MIX OF RAIN AND SNOW TO THE NORTH COUNTRY WEDNESDAY NIGHT
THROUGH THURSDAY MORNING. THIS SYSTEM IS GOING TO BE ON THE TRICKY
SIDE FOR TWO REASONS. ONE, THE LOW PRESSURE SYSTEM WILL BE MOVING
AROUND 50 MPH WHICH WILL LIMIT THE AMOUNT OF TIME THAT PRECIPITATION
WILL FALL ACROSS THE REGION. TWO, THE THERMAL PROFILES FOR THIS
EVENT ARE GOING TO BE ON THE MARGINAL SIDE FOR BOTH RAIN AND SNOW.
LET'S TAKE A DEEPER LOOK AT THE THERMAL PROFILES TO GET A BETTER
UNDERSTANDING ON WHAT IS EXPECTED TO OCCUR. TUESDAY AND WEDNESDAY
ARE BOTH EXPECTED TO BE WELL ABOVE FREEZING ACROSS THE REGION WHICH
STARTS US OFF ABOVE FREEZING WHICH IS ALWAYS A RECIPE FOR TRICKY
PRECIPITATION TYPE AND AMOUNTS. GIVEN STRONG UPPER LEVEL DYNAMICS
WITH GOOD UPPER LEVEL DIFFLUENCE, WE SHOULD SEE IMPRESSIVE WET-
BULBING AT THE ONSET OF PRECIPITATION WHICH MAY BE ENOUGH TO SWITCH
PRECIPITATION TYPE TO SNOW IN SOME LOCATIONS ALTHOUGH TEMPERATURES
WILL INITIALLY BE ABOVE FREEZING. STRONG COLD ADVECTION ALOFT IN THE
MID-LEVELS WILL QUICKLY OVERSPREAD THE NORTH COUNTRY WEDNESDAY NIGHT
ALLOWING FOR MID-LEVEL AND SURFACE TEMPERATURES TO RAPIDLY COOL
ALLOWING FOR MORE PRECIPITATION TO CHANGE OVER TO RAIN.
AT HIGHER ELEVATIONS, LIKE MOUNT MANSFIELD, WE WILL SEE MORE SNOW
THAN RAIN GIVEN THE COLD ADVECTION ALOFT HAPPENS WELL BEFORE THE
BOUNDARY LAYER. GIVEN THE ABOVE INFORMATION, WE ARE CONFIDENT MOST
PLACES WILL SEE ACCUMULATING SNOW BUT THE AMOUNT REMAINS IN
QUESTION. IN PREVIOUS EVENTS WHERE WE ARE WAITING ON THE COLD
ADVECTION TO HELP CHANGE RAIN TO SNOW, WE TYPICALLY WASTE SOME OF
THE PRECIPITATION AMOUNTS (QPF) IN THAT TRANSITION PERIOD WHICH CUTS
OUR SNOW TOTALS. IN ADDITION, ISOTHERMAL LOW-LEVEL THERMAL PROFILES
AROUND 30-32 DEGREES WILL LIKELY LEAD TO A 8-1 TO 10-1 SNOW RATIO.
AS IT STANDS NOW, IT LOOKS LIKE SNOW AMOUNTS MAY STAY JUST BELOW
ADVISORY LEVEL BUT IT'S POSSIBLE A FEW PLACES COULD SEE 3-5" OF SNOW
BELOW 1500 FT WITH SUMMITS POSSIBLY PICKING UP 8 TO 12 INCHES OF
FRESH SNOW.
THE BULK OF THE PRECIPITATION WILL TAPER OFF THROUGH THE MORNING
HOURS ON THURSDAY BUT A NICE SET-UP FOR A BACKSIDE BONUS OF UPSLOPE
SNOW SHOWERS ACROSS THE WESTERN SLOPES OF THE GREEN AND ADIRONDACK
MOUNTAINS LOOKS LIKELY. OTHER THAN A CHANCE FOR SOME SNOW SHOWERS ON
FRIDAY, THE FORECAST THROUGH EARLY NEXT WEEK LOOKS RATHER QUIET BUT
WILL BE ON THE COLD SIDE. HIGHS IN THE TEENS AND LOWS IN THE SINGLE
DIGITS ABOVE AND BELOW ZERO LOOK LIKELY SATURDAY AND SUNDAY.
AVIATION /15Z MONDAY THROUGH FRIDAY/
THROUGH 12Z TUESDAY...CURRENTLY, THERE ARE SOME POCKETS OF
2100-3000 FT AGL CEILINGS AT KMSS AND KSLK. THERE COULD BE
ADDITIONAL MVFR CEILINGS THAT REACH KMPV AT TIMES, BUT THERE
SHOULD BE LITTLE CHANGE OVER THE NEXT 6 TO 9 HOURS. SOUTH TO
SOUTHEAST WINDS WILL SLOWLY RAMP UP. AREAS LIKE KMSS WILL HOLD
ONTO A NORTHEAST OR EAST WIND THOUGH. BY 18Z-21Z, WINDS WILL
TREND TOWARDS 7 TO 12 KNOTS SUSTAINED WITH GUSTS 16 TO 22 KNOTS
LIKELY, IN ADDITION TO SOUTH WINDS AT 2000 FT AGL INCREASING TO
45 TO 55 KNOTS. LLWS IS LIKELY AT ALL TERMINALS OVERNIGHT.
AROUND 06Z TO 12Z, WINDS COULD BE AROUND 12 TO 19 KNOTS
SUSTAINED AND GUSTING 20 TO 30 KNOTS. AFTER 00Z, DRIZZLE WILL
BE POSSIBLE, MAINLY IN EASTERN VERMONT AT KMPV, AND THEN MORE
WIDESPREAD RAIN WILL QUICKLY SHIFT EAST BETWEEN 02Z AND 10Z
TUESDAY. 4-6SM VISIBILITY WILL BE POSSIBLE, IN ADDITION TO
LOWERING CEILINGS TO 800-2000 FT AGL.
OUTLOOK...
TUESDAY: MAINLY VFR, WITH AREAS MVFR POSSIBLE. WINDY WITH GUSTS
TO 30 KT. SLIGHT CHANCE SHRA.
TUESDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. NO SIG WX.
WEDNESDAY: MAINLY VFR, WITH AREAS MVFR POSSIBLE. CHANCE RA,
CHANCE SN.
WEDNESDAY NIGHT: MAINLY MVFR, WITH AREAS IFR POSSIBLE. DEFINITE
SN, LIKELY SHSN, DEFINITE RA.
THURSDAY: MAINLY MVFR, WITH LOCAL IFR POSSIBLE. CHANCE SHSN.
THURSDAY NIGHT: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. NO SIG WX.
FRIDAY: MVFR. CHANCE SHSN.
MARINE
SOUTH WINDS 15 TO 30 KNOTS ARE ANTICIPATED THROUGH THE NEXT 12
TO 18 HOURS OVER LAKE CHAMPLAIN. AFTER MIDNIGHT, WINDS ARE
EXPECTED TO INCREASED TO 25 TO 35 KNOTS, WITH GUSTS AS HIGH AS
45 KNOTS POSSIBLE. WAVES WILL BE ANYWHERE FROM 1 TO 5 FEET
TODAY. DURING THE OVERNIGHT HOURS, WAVES ON THE BROAD WATERS MAY
BRIEFLY INCREASE TOWARDS 5 TO 7 FEET AS GUSTS OF 45 KNOTS
DEVELOP. WINDS WILL DECREASE TOWARDS 10 TO 20 KNOTS AS THEY
SHIFT SOUTHWESTERLY.
EQUIPMENT
PLATTSBURGH ASOS IS MISSING VISIBILITY IN REPORTS AND IS
AWAITING A PART TO FIX THIS ISSUE, WHICH IS CURRENTLY
UNAVAILABLE UNTIL FEBRUARY 1.
BTV WATCHES/WARNINGS/ADVISORIES
VT...WIND ADVISORY FROM 7 PM THIS EVENING TO 4 PM EST TUESDAY FOR
VTZ001>003-016.
NY...WIND ADVISORY FROM 7 PM THIS EVENING TO 4 PM EST TUESDAY FOR
NYZ027-028-030-031-034.
SYNOPSIS...HAYNES
NEAR TERM...HAYNES/TABER
SHORT TERM...CLAY
LONG TERM...CLAY
AVIATION...HAYNES
MARINE...TEAM BTV
EQUIPMENT...TEAM BTV
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