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000
FXUS61 KBTV 241111
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
711 AM EDT Mon Jul 24 2017

.SYNOPSIS...
Upper low pressure will cross the area today into tonight with
widespread rainfall and cool temperatures before exiting east on
Tuesday. High pressure brings a brief stretch of fair weather
on Wednesday before a weak cold front brings a renewed threat of
showers and storms on Thursday. Fair weather then returns for
Friday into next weekend with temperatures near seasonal late
summer norms.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 310 AM EDT Monday...A soggy, damp and dreary 24-36 hours
remains on tap for our area today into Tuesday morning as upper
low pressure and an accompanying 500 mb longwave trough slowly
pivot through the area. Good PVA and diffluence aloft will aid
dynamical support for upward motion and rainfall through the
period, some of which could be heavy at times across our
northern New York counties today into early this evening.
Instability remains rather marginal and have kept with prior
thinking confining any lower thunder threat in these western
counties only into this evening where modestly steep mid-level
lapse rates exist. Given the expected lack of intense rainfall
rates and seasonable 3/6 hr flash flood headwater guidance
values, the threat of flash flooding still appears low at this
point, despite a marginal risk area being maintained in our area
by WPC. That said, model-blended QPF totals shown for this
event will range from 0.50 to 1 inch across VT and from 1 to 2
inches in northern NY through Tuesday morning with localized
totals to 2.5 inches in portions of the SLV where some modest
watershed rises will be possible. Temperatures will trend quite
cool by late July standards with readings only topping out in
the upper 50s to mid 60s today, coolest across northern NY.
Winds mainly light east to southeasterly, though a brief window
of southeasterly gusts to perhaps 25-35 mph will exist along the
western slopes of the central and southern Greens this morning
through mid-afternoon or so.

By tonight showers will remain quite abundant in coverage,
though wane in overall intensity as the system continues to
pivot slowly east. Patchy br/fog also a good bet just about
anywhere as temperatures hold in the 50s. Winds light.

On Tuesday widespread morning showers gradually move east
and/or fade away as longwave trough exits east and building high
pressure advances east from the Great Lakes and Ohio Valley.
Plenty of clouds should be the rule most of the day, though some
partial sunshine will be possible from the Champlain Valley
west by later in the afternoon. Temperatures remain on the cool
side in the 60s, possibly touching the 70F mark in the SLV where
partial sun may arrive a bit earlier than other areas.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
As of 333 AM EDT Monday...Dry weather will persist Tuesday
night and Wednesday with upper level and surface ridging over
the area. Decreasing cloud cover Tuesday night will set us up
for some fog formation, locally dense, from 06-12z. Surface high
crests over the region on Wednesday, with warm southwesterly
flow developing. Cooler than normal temperatures Tuesday night,
mainly 50s with some 40s in the Dacks. Temps rebound nicely on
Wednesday with near seasonal normals expected, upper 70s to
around 80.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 333 AM EDT Monday...All of the weather in the long term
will be in the first few periods, mainly Wednesday night and
Thursday. A cold front will push across the region with showers
and perhaps thunderstorms Thursday afternoon. This will depend a
lot on the timing of the front which will become more clear as
we get closer to Thursday. Have mentioned likely pops for
Thursday, because this looks like the time period when the fropa
will happen. Showers should be ending during the first part of
Thursday night, though Euro does depict a slower system. Right
now the Friday through Sunday timeframe looks quiet with large
ridge of surface high pressure over the region. Temperatures
will be near normal through the week.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
Through 12Z Tuesday...Deteriorating conditions expected across
the area today into tonight as upper low pressure brings
widespread rainfall to the region. Thunder threat rather low and
confined to northern New York counties. Lack of expected
coverage warrants omission from NY terminal forecasts at this
point. Generally looking at VFR trending MVFR at all terminals
in the 09-18Z time frame as rain arrives from southwest to
northeast. Exception at KSLK where patchy IFR stratus will
linger a few hours this morning before trending MVFR. Brief IFR
visibilities possible in heavier showers, especially in northern
NY. Showers trend a bit lighter after 00Z Tuesday, though
scattered coverage remains across the area as cigs lower into
the 005-015 AGL range (IFR/MVFR) with widespread 3-5sm br and
localized areas below 2sm. Winds east to southeasterly through
the mainly in the 5 to 15 knot range, though occasionally gusty
to 30 kts at KRUT in the 12-00Z time frame, trending light after
00Z.

Outlook...

Tuesday: VFR. Chance SHRA...Patchy morning FG.
Tuesday Night: VFR. Patchy dense FG.
Wednesday: VFR.
Wednesday Night: VFR. Slight Chance SHRA.
Thursday: VFR/MVFR. Likely SHRA...Chance TSRA.
Thursday Night: VFR. Chance SHRA.
Friday: VFR/MVFR. Slight Chance SHRA.

&&

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

&&

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