FXUS61 KBTV 151956

National Weather Service Burlington VT
356 PM EDT Sat Jun 15 2019

Breezy south to southwesterly winds continue today ahead of a
cold front approaching from southwestern Quebec and southeastern
Ontario. Showers will become more widespread as the the cold
front tracks across northern New York late this afternoon, and
during the evening hours across northern Vermont. While showers
will be widespread rainfall totals will be somewhat limited by
terrain and so expect amounts between a tenth and quarter inch.
For Sunday, the boundary settles over the Vermont and
Massachusetts border allowing for partly cloudy skies and
generally quite weather across the North Country. Dry and
seasonable conditions are expected Sunday night and Monday.


As of 351 PM EDT Saturday...Its been quite a blustery day
across the North Country as partial clearing this afternoon
allow temps to warm a few degrees warmer than initially
thought. This mean that lapse rates steepened and we were able
to mix slightly higher across the Champlain and Saint Lawrence
Valleys. The 25 to 35 mph winds will start to abate as a cold
front brings widespread rain showers to the region. The front
has been a little slower to track through the North Country but
expect between 4 to 6 pm this evening showers will develop
ahead of and along the frontal axis and move towards the south
to southeast bringing widespread light rain to northern New York
and then by 8 to 10 pm into Vermont. The exception will be
across the Champlain Valley where a modestly strong low level
jet out of the southwest will shadow the Champlain valley and
significantly lower our rainfall totals.

The front sags through the region and becomes stalled just to
our south across the MA/VT border just before sunrise tomorrow
morning. All totaled we're looking at between a tenth of an
inch here in the Champlain Valley and outside the Champlain
valley upwards of a quarter to a third of an inch. Right behind
the front expect the winds to relax and weaken which will lead
to the possibility of some patchy fog developing mainly over the
Saint Lawrence Valley but I certainly can't rule out more
widespread fog. Temps will fall this evening into the mid to
upper 50s but still remain a degree or two above normal.

Sunday should be a pleasant and quiet day for most of the North
Country. With the front stalled to our south and weak ridging
we'll see temps in the upper 60s to low 70s under partly cloudy
skies. Parts of southeastern Windsor county could see a an
isolated shower or two but I'm not expecting much precip at all.
Sunday night remains a pleasant one as temps drop to near
normal under light northerly winds and variable cloud cover.


As of 336 PM EDT Saturday...For Monday, weak surface high
pressure will settle over the region with drier air filtering
into the region behind Sunday's activity. Skies should be mostly
clear to partly cloudy before some mid to high level clouds
stream over the region later in the day. Weak cold- air
advection present, but with high pressure and clear skies, we
should see temperatures reach seasonal norms. Low temperatures
for Monday night similar to previous night with 50s across the
North Country and calm winds.


As of 336 PM EDT Saturday...Tuesday should be fairly quiet as
well with low pressure passing to our south on its way to the
Atlantic Ocean. There is a weak trough axis on its north side
that I do not completely trust, and the latest GFS output
indicates some marginal surface instability, so an isolated
shower could develop across mainly south-central Vermont.
Wednesday will be rinse and repeat with another weak surface low
and shortwave passing to our south. The 300K isentrope
indicates a bit more moisture streaming north with some cross-
isobaric flow so isolated to scatter showers possible across the
North Country in the afternoon.

A more impressive system approaches late Thursday as a compact,
negatively tilted shortwave lifts northeast into New England
along with a stacked 998mb surface low. Deterministic output
indicates the potential for moderate to locally heavy rain. A
few individual ensemble members are starting to catch on, but
there does remain some spread. Synoptic forcing is favorable
with excellent Q-vector convergence over the North Country and
with a semi-coupled upper jet structure developing. Efficient
moisture transport should bring 1.5 to 1.75" PWATs into our area
and the low track is favorable for a good soaking. There are a
few timing discrepancies with EC/CMC trending closer to Thursday
afternoon and the GFS trending closer to overnight Friday into
the morning hours. Depending on time of day, there could be some
thunder as well. We will closely monitor the progress of this

As far as temperatures are concerned, we will experience a warm up
Tuesday and Wednesday with the latest GFS MOS forecasting 80s
on Tuesday and Wednesday and the EC MOS just shy of 80. Based
on 925mb temps of about 18-19C, Wednesday looks the more likely
day to reach 80 degrees and have added a few spot 80s across
the Champlain and St. Lawrence Valley. With the approaching
system later in the week, temperatures will cool into the
weekend. Lows will fluctuate little, remaining generally in the


Through 18Z Sunday... Generally expect VFR through the day
today with lowering ceilings and some brief visibility
reductions this evening as a rain showers associated with a
frontal system track through the North Country. Ceilings lower
even further behind the front as flight conditions should become
MVFR. Ceilings will drop to 1000-1200 feet at MSS/SLK behind
the front overnight and will likely hover right between low MVFR
and IFR. Anticipate with the rainfall this evening that as the
winds decouple behind the front some ground fog or mist may end
up developing over portions of northern New York especially in
the Saint Lawrence Valley. So I've opted to go ahead and bring
in some IFR visibility at MSS just briefly before sunrise.

The main issue through the rest of the daylight hours remain
the gusty winds. Will see sustained winds southerly to
southwesterly 12-17kt with gusts 25-35kt possible, likely
highest at BTV and MSS with valley channeling. Winds gradually
diminishing toward early evening as the cold front approaches
from southeastern Ontario.


Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. Slight chance SHRA.
Tuesday Night: VFR. Slight chance SHRA.
Wednesday: VFR. Slight chance SHRA.
Wednesday Night: VFR. NO SIG WX.
Thursday: Mainly VFR, with local MVFR possible. Chance SHRA.




LONG TERM...Haynes
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