Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
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FXUS61 KBTV 271427
Area Forecast Discussion
National Weather Service Burlington VT
1027 AM EDT Tue Sep 27 2016
A frontal system will move east through the north country early
this morning. Mainly dry weather will be over the north country
today through Thursday. An upper low will bring a chance of
showers to the region from Thursday night through this weekend.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 1027 AM EDT Tuesday...Surface occluded front continues to
shift east of the North Country this morning, and in it`s wake
dry conditions and variable cloudiness can be expected through the
day. Noting a few lake enhanced showers and even thunderstorms
developing off Lakes Erie and Ontario and while confidence is
rather low they`ll make it into the BTV CWA have opted to include
some slight to low chance pops across St. Lawrence county through
the day. Temps are on track to be back above seasonal normals,
rising into the mid 60s to low 70s this afternoon.
Tonight, expecting a mainly dry forecast with partly cloudy skies.
lows will be mainly in the 40s to lower 50s in some valley
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
As of 351 AM EDT Tuesday...Large scale pattern shows closed 5h/7h
circulation across the Ohio Valley with building ridge both aloft
and at the surface across eastern/southern Canada. This complex
and nearly stationary pattern will produce above normal
temperatures and several chances for precip. However...latest
trends show best potential of heavier rainfall staying closer to
the upper level circulation over the Ohio Valley and Mid Atlantic
States through Thursday. Have continued with a mainly dry forecast
for Weds...as best energy and moisture is located over the Ohio
Valley. An isolated shower or sprinkle is possible over the
mountains and have mention slight chance pops to cover this
potential. Progged 850mb temps near 7c support highs well into the
60s with a few 70s possible...especially if we can see some sun in
the warmer valleys. By Thursday...have noted easterly 850mb flow
of 15 to 25 knots...may help to advect low level moisture into
central/eastern vt. Still plenty of uncertainty on depth of
moisture and placement...so high only mention chance pops across
southern/eastern VT on Thursday...with some areas of drizzle
possible in the mountains. Thinking additional clouds will keep
southeast cwa cooler with highs mainly in the 60s...but lower 70s
possible Saint Lawrence Valley...with lows mainly in the 50s.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 351 AM EDT Tuesday...Little change in the overall synoptic
pattern is expected through Saturday...as closed mid/upper level
low pressure continues to sit and spin across the Ohio Valley.
Eventually pattern will break down and cyclonic circulation will
weaken as it lifts across the NE CONUS by next weekend. Still
plenty of uncertainty on the overall impacts of system and
placement of best deep layer moisture and upper level support.
Latest trends show best moisture/lift remaining to our south
through Friday...with only weak embedded vorts lifting across our
cwa...resulting in chc pops. Furthermore....seems like moisture
fields and associated qpf weaken as it encounters dry air
associated with surface ridge. Guidance shows a tight north to
south precip gradient across central New England into the Mid
Atlantic...given this scenario have continuity to mention chc
pops during the Thurs Night into Saturday time period. Best chance
for measurable qpf will be along the se upslope regions of the
green mountains of central/southern vt during this time period.
Also...prevailing east to southeast flow may result in areas of
low clouds and drizzle...with cooler temps. Thinking highs will
generally range from the upper 50s/lower 60s mountains of eastern
VT to lower 70s Saint Lawrence Valley with near 70f for the
Champlain Valley. Have kept temps several degrees above superblend
because of clouds...with lows mainly in the 50s...which is above
10 degrees above normal.
.AVIATION /15Z Tuesday THROUGH Saturday/...
Through 12Z Wednesday...Rain showers have moved well east of the
region as of 1130Z today. Expecting mainly VFR conditions
throughout the region by 15Z Tuesday.
Outlook 12z Wednesday through Saturday...
12z Wed - 00z Thu: Generally VFR, though an MVFR marine layer may
intrude from the east late Tuesday night through mid-day
00z Thu - 00z Sun: Mainly VFR with MVFR in rain showers possible,
especially on Saturday.