Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
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FXUS61 KBTV 292324
Area Forecast Discussion
National Weather Service Burlington VT
724 PM EDT Mon Aug 29 2016
A ridge of high pressure will build east from the Great Lakes
overnight and will crest over the north country on Tuesday. A cold
front will move south from Canada on Wednesday and will bring a
chance of showers and thunderstorms to the north country on
Wednesday. A ridge of high pressure over Canada and the western
Great Lakes on Thursday will build slowly east and will be over
the north country from Thursday through Labor Day, with fair and
dry weather expected.
.NEAR TERM /THROUGH TUESDAY/...
As of 645 PM EDT Monday...Fair weather cumulus clouds are rapidly
dissipating per visible satellite imagery at 2230Z with onset of
diurnal cooling cycle. Expecting mainly clear skies overnight, and
northwest winds will become light and variable as PBL stabilizes
after sunset. Should see patchy dense radiational fog in the
normally favored valleys within the northern Adirondacks and the
valleys of central/ern VT. Lows temperatures will mainly be in the
50-55F range overnight, except in the 40s over the Adirondacks and
portions of the Northeast Kingdom of Vermont.
On Tuesday, expecting any morning valley fog to burn off early,
with mostly sunny skies expected throughout the balance of the
morning. Expecting an increase in mid to upper level clouds from
NW-SE across the North Country during the afternoon with a weak
upper level wave approaching from southeastern Ontario. Temperatures
will climb to the upper 70s to the lower 80s for highs Tuesday
afternoon, as the ridge of high pressure crests over the region.
2-M dewpoints will remain pleasantly low, generally in the 50s.
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 332 PM EDT Monday...Tuesday night will start dry with
increasing clouds and moisture towards Wednesday morning. Chance
for precipitation will also increase as surface trough approaches
ahead of mid level trough with vort max south of James Bay by 12Z
Wednesday. Some instability providing a slight chance to chance of
thunderstorms during the day Wednesday. Trough will dig into the
eastern Great Lakes for the latter half of Wednesday into
Wednesday night behind surface cold front that pushes southeast
across the North Country. Expect most precip to exit south and
east before 12Z Thursday as drier air filters in behind the cold
front in NW low level flow.
Temperatures around normal but a few degrees cooler Wednesday
night in the wake of the front.
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 332 PM EDT Monday...Lingering clouds and possibly a few
showers mainly across the Northeast Kingdom and areas near the
international border as the main 500mb trough progresses over the
North Country with every pieces of vorticity embedded in the flow
move through the base of the trough. Come Thursday night, PWATs
drop below 1 inch and North to Northwest flow takes over at the
surface through mid levels. High pressure will build over the
Great Lakes Friday shifting over the eastern Great
Lakes/southwestern Quebec Saturday. This ridge at the surface and
aloft will keep a potential tropical system originating in the
Gulf of Mexico (currently Tropical Depression 9) to our south and
east at least through Sunday. GFS and ECMWF begin to diverge on
strength and position of ridge that far out, but another 500mb
trough developing west of James Bay and digging into the Great
Lakes looks to help keep the tropical system offshore. At this
time, expect dry weather across the North Country Thursday night
through Monday/Monday night.
Temperatures will be noticeably cooler for the first few days of
the period. Max temps Thursday range from the mid 60s to mid 70s
with chilly nights expect Thursday night and Friday night. Min
temps in the mid 40s to mid 50s the first night will be cooler
about 5-10 degrees cooler as ridge of high pressure crests of the
region and ideal radiational cooling results. Temperatures recover
to near normal Sunday through the rest of the period.
.AVIATION /00Z Tuesday THROUGH Saturday/...
-- Changed Discussion --Through 00Z Wednesday...mainly VFR except VLIFR in fog expected
at KMPV/KSLK 06-12Z. A ridge of high pressure will move east from
the Great Lakes overnight and will crest over the region on
Tuesday. Expecting some areas of radiation fog to develop in the
usual fog prone valleys of eastern and northeast Vermont, as well
as the valleys of the Adirondacks. Any fog should burn off by 13Z
Tuesday. Expecting surface winds after 00z Tuesday to be nearly
calm or light and variable. Expecting increasing middle to high
clouds across the region after 14Z Tuesday in addition to some
cumulus clouds mainly over the mountains.
Outlook 00Z Wednesday through Saturday...VFR conditions expected
through 12Z Wednesday. A cold front moving south from Canada on
Wednesday will bring a chance of showers and thunderstorms to the
region with some areas of MVFR and IFR possible.
Expecting mainly VFR conditions from 06Z Thursday through Sunday,
as a ridge of high pressure over the western Great Lakes and
Canada builds slowly east into the region through the period.
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