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000
FXUS61 KBTV 171108
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
708 AM EDT Thu Aug 17 2017

.SYNOPSIS...
High pressure over the area today will bring dry weather to the
area with high temperatures in the 70s to around 80. A warm
front will approach the region later tonight from the southwest
and enhance the potential for showers and a few thunderstorms
across the area...especially over northern New York. Showers and
a few thunderstorms will exist over the entire area from time
to time...with the potential for some stronger storms over
northern New York late in the day on Friday. Showers and storms
will taper off Friday night...but scattered showers will exist
over the area on Saturday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 707 AM EDT Thursday...Any fog will burn off quickly this
morning and area will just be dealing with mid and high level
clouds in the northwest flow aloft. Not expecting any
precipitation with highs in the 70s to around 80.

For tonight...a well defined warm front will move into the
region from the southwest and enhance the threat of showers and
embedded thunderstorms across northern New York after midnight.
Sharp dew point gradient clearly defines the front and with
noticeable warm air advection at 850 mb...showers should be
likely with the front. Sharp gradient of Showalter Index values
moves into northern New York after midnight and this will
enhance the potential for elevated convection.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
As of 503 AM EDT Thursday...Showers and a few thunderstorms
will be ongoing across much of the area Friday morning as warm
front lifts northeast across the region. Areal coverage of the
showers should decrease around midday as warm front lifts north
of the border. Composite analysis shows northern New York
getting into the warm sector and instability should develop with
highs in the 70s and dew points in the 65 to 70 degree range.
At the same time deep layer shear will be increasing over the
top of the instability and would expect the potential for
thunderstorms to develop in advance of the approaching cold
front. Will have to keep an eye on this situation because if
sufficient instability develops storms may get organized enough
to produce gusty winds...hail...and heavy downpours. Mid level
lapse rates are not impressive and thus will need surface
heating to help drive the development of instability. Best
instability may be across central and southeast New York where
shear is a bit weaker. Precipitable water values in this area
will be around 2 inches as well. Clouds and showers over Vermont
on Friday will keep highs in the upper 60s to mid 70s...but
over northern New York highs will be in the 70s to around 80.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 503 AM EDT Thursday...Mainly dry weather is expected from
Saturday night through Tuesday morning. Cold air advection
continues Saturday night behind departing surface cold front
that crossed the area Friday night. Ridge of surface high
pressure centered over Ohio river valley will build into our
region and remain through early Tuesday. An upper level trough
will push across our forecast area Saturday night and Sunday.
Looks like good eclipse viewing weather for Monday afternoon.
Southwest flow will develop Tuesday as surface ridge moves East
of the region, this flow will also advect some much warmer air
into the North Country. A low pressure system will pass from the
Northern Great Lakes area on Tuesday Northeastward into Central
Quebec on Wednesday. Best chance for rain showers will be
Tuesday night into Wednesday with surface cold frontal passage.
Upper level trough will lag behind a bit, crossing our area
Thursday night into Friday. Overall the work week looks
unsettled.

&&

.AVIATION /11Z THURSDAY THROUGH MONDAY/...
Through 12Z Friday...Overall looking at VFR conditions through
much of the period. However...after 04z conditions will trend
toward the MVFR category as a warm front moves into northern New
York. Showers will increase in areal coverage over northern New
York and the potential for some thunderstorms will also exist to
help lower ceilings and visibilities. The Champlain Valley may
see some showers and storms right toward the end of the period
along with the trend to MVFR conditions. Winds will generally be
under 10 knots through about 06z...then increase from the
southeast during the remainder of the period.

Outlook...

Friday: VFR/MVFR. Likely SHRA...Slight Chance TSRA.
Friday Night: VFR. Likely SHRA...Slight Chance TSRA.
Saturday: VFR. Chance SHRA...Slight Chance TSRA.
Saturday Night: VFR. Slight Chance SHRA.
Sunday: VFR. Slight Chance SHRA.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.

&&

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

&&

$$
SYNOPSIS...Evenson
NEAR TERM...Evenson
SHORT TERM...Evenson
LONG TERM...Neiles
AVIATION...Evenson