Area Forecast Discussion
Issued by NWS Burlington, VT

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KBTV 252310
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
710 PM EDT WED MAR 25 2015

.SYNOPSIS...
A WARM FRONT WILL BRING PERIODS OF LIGHT RAIN TO THE NORTH
COUNTRY THIS EVENING...FOLLOWED BY ANOTHER SURGE OF RAIN MID-
MORNING THURSDAY. A MIX OF RAIN AND SNOW THURSDAY NIGHT INTO
FRIDAY WILL DEVELOP AS A COLD FRONT TRACKS THROUGH THE REGION.
TEMPERATURES WILL TREND COLDER INTO THE FIRST HALF OF THE
WEEKEND...REBOUNDING NEXT WEEK.

&&

.NEAR TERM /UNTIL 8 AM THURSDAY MORNING/...
AS OF 426 PM EDT WEDNESDAY...VERY DRY AIR OVER THE NORTH COUNTRY,
WITH SURFACE TEMPERATURE DEWPOINT SPREADS EXCEEDING 30 DEGREES,
WILL CAUSING RAIN ASSOCIATED WITH WARM FRONT TO EXPEND MUCH OF ITS
MOISTURE TRYING TO SATURATE THE ATMOSPHERE. AS THE WARM FRONT
LIFTS SOUTHWEST TO NORTHEAST, DO EXPECT SOME RAIN SHOWERS WITH
LIGHT QPF AMOUNTS GENERALLY LESS THAN A TENTH OF AN INCH WITH
EXCEPTION OF SW ST LAWRENCE VALLEY. THE FRONT LOOKS TO CLEAR THE
NORTH COUNTRY SHORTLY AFTER 06Z WITH A DRY SLOT FILTERING IN
BEHIND IT.

CLOUDS OVER THE AREA MOST OF THE NIGHT COMBINED WITH WARM
SOUTHERLY FLOW IN THE WARM SECTOR, EXPECT MINIMUM TEMPERATURES IN
THE 30S.

&&

.SHORT TERM /8 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 426 PM EDT WEDNESDAY...PRECIPITATION CHANCES INCREASE
THURSDAY MORNING AS A SECOND STRONGER TROUGH DIGS INTO THE GREAT
LAKES ASSOCIATED WITH A NEW SURFACE LOW LIFTING NORTHEAST FROM THE
OHIO RIVER VALLEY INTO SOUTHERN NEW ENGLAND LATE THURSDAY. THIS
LOW WILL TRACK TO THE GULF OF MAINE BY FRIDAY MORNING. THIS NEW
SYSTEM WILL HAVE PWATS NEARING ONE INCH AND STRONGER
DEFORMATION/FRONTOGENETIC ZONE OVER CENTRAL/SOUTHERN VERMONT.
EXPECT WIDESPREAD RAINFALL BY THURSDAY AFTERNOON WITH PERIODS OF
MODERATE RAIN POSSIBLE MAINLY FOR THE SOUTHERN THIRD OF THE
FORECAST AREA. RAINFALL AMOUNTS WILL RANGE FROM 0.20-0.50 INCH
DURING THE DAY WITH TEMPERATURES REACHING THE 40S.

A SURFACE COLD FRONT WILL MOVE THROUGH THURSDAY NIGHT WITH A
TRANSITION TO A MIX OF RAIN AND SNOW WITH MAINLY SNOW OVER THE
NORTHERN MOUNTAINS...THOUGH PRECIPITATION WILL BEGIN TO TAPER OFF
AFTER MIDNIGHT. LIGHT SNOWFALL ACCUMULATIONS OF A DUSTING TO 2
INCHES ARE POSSIBLE OVERNIGHT WITH MINS FALLING TO THE UPPER 20S
TO LOWER 30S.

SNOW OR RAIN SHOWERS WILL CONTINUE FRIDAY IN LINGERING MOISTURE
BEHIND COLD FRONT AS POSITIVELY TILTED UPPER TROUGH AND ASSOCIATED
VORT PROVIDE LIFT, WHILE N-NW FLOW AT THE SURFACE FOCUSES THE
PRECIPITATION AROUND THE TERRAIN. MAINLY SNOW ACROSS NORTHERN YORK
AND THE HIGHER TERRAIN OF VERMONT WHERE HIGHS WILL BE ONLY IN THE
LOWER 30S. MORE OF A MIX EXPECTED IN THE VALLEYS OF VERMONT WITH
HIGHS 35 TO 40.

HIGH PRESSURE BUILDS OVER THE MID-WEST WITH THE AXIS EXTENDING
INTO QUEBEC. THIS WILL FILTER IN DRIER AIR ENDING SNOW SHOWERS BUT
KEEPING TEMPERATURES COLD FRIDAY NIGHT WITH MINS IN THE SINGLE
DIGITS TO TEENS.

WITH THE EXPECTED RAINFALL OF 0.50-0.85 INCH THROUGH FRIDAY AND
ABOVE FREEZING TEMPERATURES THROUGH EARLY THURSDAY NIGHT CAUSING
SNOWMELT, EXPECT SOME ICE MOVEMENT...ESPECIALLY IN OUR SOUTHERN
RIVERS. FOR MORE ON THAT SEE OUR HYDRO SECTION BELOW.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 426 PM EDT WEDNESDAY...COLD SURFACE HIGH PRESSURE WILL BE
IN PLACE FOR SATURDAY AND SUNDAY PROVIDING THE REGION WITH DRY
WEATHER AND COLD TEMPERATURES. A SERIES OF FRONTAL PASSAGES WILL
BRING CHANCES FOR SHOWERS DURING THE FIRST HALF OF THE WORK WEEK
ACROSS NORTHERN NEW YORK AND VERMONT.

DRY COLD WEATHER IS EXPECTED SATURDAY WITH CLEARING SKIES DURING
THE AFTERNOON AND OVERNIGHT. MAX TEMPERATURES WILL BE IN THE MID
TO UPPER 20S...LOWER 30S IN SOUTHERN VERMONT. SATURDAY NIGHT WILL
CONTINUE COLD AND DRY WITH SINGLE DIGITS AND TEENS ACROSS THE
AREA. WARM AIR ADVECTION WILL BEGIN SUNDAY AS SURFACE HIGH SLOWLY
MOVES EASTWARD AND HIGH TEMPS WILL REACH THE MID TO UPPER
30S...NEAR 40 IN SOUTHERN VERMONT. CLOUDS MOVE INTO THE REGION
SUNDAY NIGHT AND MONDAY AHEAD OF NEXT APPROACHING SYSTEM. A LOW
PRESSURE SYSTEM WILL PASS NORTH OF OUR FORECAST AREA MONDAY
DRAGGING A COLD FRONT ACROSS THE REGION. GENERALLY WIDESPREAD
SHOWERS...THOUGH LIGHT...CAN BE EXPECTED...BEGINNING AS SNOW
SHOWERS SUNDAY NIGHT THEN MIXING WITH AND CHANGING TO RAIN SHOWERS
ON MONDAY. THIS SYSTEM WILL BE PRETTY SLOW PUSHING EASTWARD...WITH
SHOWERS LINGERING EVEN INTO EARLY TUESDAY BEFORE ANOTHER WEAKER
SURFACE HIGH RIDGES INTO THE AREA TUESDAY NIGHT AND WEDNESDAY.
TEMPERATURES WILL TREND BACK TOWARDS NORMAL LEVELS BY THE END OF
THE PERIOD.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
THROUGH 00Z FRIDAY...RELATIVELY ACTIVE, CHANGEABLE AVIATION
PERIOD AS VFR CONDITIONS LOWER TO MAINLY. LOW-LEVEL WIND SHEAR AND
PRECIP TYPE CHANGES ARE ADDITIONAL AVIATION FORECAST CONCERNS.

COMPOSITE RADAR SHOWS SOLID BAND OF WARM-FRONTAL PRECIP
APPROACHING NORTHERN NY INTO THE LOWER CHAMPLAIN VALLEY. SOME
35-45 DBZ ECHOES BEING OBSERVED WITH FRONTAL PRECIP. BASED ON
RECENT ALB METARS AND KENX DUAL-POLARIZED DOPPLER RADAR DATA,
RAIN MAY MIX WITH GRAUPEL/ICE PELLETS IN THESE HEAVIER ECHOES.
THIS BAND LIFTS NORTHEAST THROUGH 03Z. IN ITS WAKE, CEILINGS
LIKELY TO DROP TO MVFR WITH SPOTTY IFR. AREAS OF DRIZZLE AND MIST
AS DRY AIR WORKS ITS WAY ABOVE STRATUS. WINDS SOUTH 10-15 KTS WITH
INTERVALS OF GUSTS. I`VE ALSO MENTIONED LLWS AT BTV AND PBG BASED
ON CXX VWP OF 50 KTS AT 2 KFT.

FOR THURSDAY: MVFR CEILINGS WITH PERIODS OF DRIZZLE/MIST INTO THE
MORNING HOURS. NEXT WAVE OF COLD FRONTAL PRECIP APPROACHES TOWARD
15-17Z. WITH COOLING TEMPERATURE PROFILES, INITIAL RAIN CHANGES
TO RAIN/WET SNOW MIX, THOUGH THAT CHANGEOVER OCCURS PRIOR TO 00Z
THURS ONLY AT MSS AND SLK. SOUTH WINDS AROUND 10 KTS BECOMING MORE
VARIABLE WITH FRONT.

OUTLOOK 00Z FRIDAY THROUGH SUNDAY...

00Z FRIDAY - 12Z FRIDAY...MAINLY MVFR (BRIEF IFR POSSIBLE) AS
RAIN CHANGES TO SNOW SHOWERS AS COLD FRONT MOVES THROUGH.

12Z FRIDAY - 00Z SUNDAY...MIX OF VFR AND MVFR WITH SCATTERED SNOW
SHOWERS POSSIBLE.

00Z SUNDAY - 00Z MONDAY...VFR CONDITIONS UNDER RIDGE OF HIGH
PRESSURE.

00Z MONDAY - TUESDAY...MVFR POSSIBLE IN SHOWERS.

&&

.HYDROLOGY...
AS OF 426 PM EDT WEDNESDAY...THREAT FOR POTENTIAL ICE BREAKUP AND
JAMMING IS LOWER WITH THIS FORECAST CYCLE. PERIOD OF ABOVE
FREEZING TEMPERATURES WILL RELEASE SNOW MELT, AND WHEN COMBINED
WITH THURSDAY RAINFALL WILL PRODUCE WITHIN BANK RISES ON RIVERS.
RAIN THAT ARRIVES WITH WARM AIR ADVECTION TONIGHT WILL BE ABSORBED
BY COLD SNOWPACK WITH LITTLE IMPACT ON RIVERS. SOUTH WINDS AND
INCREASING DEWPOINTS WILL BEGIN MELT OF SOME SNOW ON THURSDAY,
THEN RAIN ARRIVES ALONG/AHEAD OF COLD FRONT LATE THURSDAY.

TREND TOWARD SLIGHTLY COOLER TEMPERATURES AND LOWER FORECAST
RAINFALL IS HAVING EFFECT OF REDUCING FORECAST RIVER RISES. A FEW
DEGREES COOLER WILL SLOW RATE OF SNOWMELT FROM PREVIOUS FORECAST,
ESPECIALLY OVER HIGHER TERRAIN. DURATION AND INTENSITY OF WARMER
TEMPS BASED ON LOCALLY RUN ACCUMULATED THAWING DEGREE HOURS TOOL
SHOWS THREAT AREA ONLY AT LOWEST ELEVATIONS BUT HIGHER TERRAIN
REMAINING TOO COOL. WILL LIKELY LOSE MOST SNOW ON VALLEY FLOORS IN
THIS WARMUP BUT HIGHER TERRAIN WILL MELT LESS. RAINFALL FORECASTS
HAVE BACKED OFF TO THREE QUARTERS INCH IN THE SOUTH TO A HALF INCH
ALONG THE CANADIAN BORDER. THESE LESSER AMOUNTS WILL BE MORE
LIKELY TO ABSORB INTO SNOWPACK RATHER THAN RUN OFF.

FORECAST RIVER RISES NOW MORE LIKE TWO TO FOUR FEET, WHICH IS
BARELY SUFFICIENT TO BEGIN TO BREAK UP AND MOVE OUR RIVER ICE THAT
IS 1 TO 1.5 FEET THICK. WE MIGHT GET SOME ICE BREAKUP ON SMALLER
TRIBUTARIES, ESPECIALLY IN THE SOUTH, BUT ANY IMPACTS WILL BE
ISOLATED. STILL NEED TO MONITOR RIVERS FOR ICE MOVEMENT THURSDAY
NIGHT INTO FRIDAY.

&&

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

&&

$$
SYNOPSIS...KGM
NEAR TERM...KGM
SHORT TERM...KGM
LONG TERM...NEILES
AVIATION...NEILES/LOCONTO
HYDROLOGY...HANSON



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.