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000
FXUS61 KBTV 252025
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
425 PM EDT Sun Jun 25 2017

.SYNOPSIS...
Unsettled weather will continue across the region throughout the
entire week with a daily threat of showers and a few thunderstorms.
Some of the rainfall may trend heavy, especially later in the week
as a more humid airmass moves into the area. Temperatures will
remain close to seasonal early summer norms through the period.

&&

.NEAR TERM /THROUGH MONDAY NIGHT/...
As of 325 PM EDT Sunday...Scattered showers and a few heavier
thunderstorms continue across the area this afternoon in advance
of of a vigorous shortwave to the immediate north of Lake
Ontario. A few of the cells have produced small hail and gusty
winds, which is not surprising given relatively low freezing
levels near 9 kft and a near dry adiabatic sub-cloud layer. The
shortwave feature will progress bodily east across the northern
half of the area this evening when best threat of scattered
showers/isolated storms occur, then exit east overnight with
coverage waning. Lows a blend of available guidance showing
values mainly in the 50s.

More active weather still on tap for Monday as yet another strong
shortwave drops into the central Great Lakes area. Low level surface
trough boundary connecting today`s shortwave (then across the
Canadian Maritimes) to the Great Lakes feature will serve as focus
for low level convergence and additional showers/isolated
thunderstorms by tomorrow afternoon. Best coverage to occur during
peak heating hours of noon to 6 pm or so before covering slowly
wanes into the evening and especially overnight hours. Low to mid
level lapse rates are poorer than today and with cooler boundary
layer temperatures per 925-850 mb progs updraft strength in
convective cores will not be as robust. Thus no strong to
severe storms are expected. Highs tomorrow mainly from the mid
60s to lower 70s with lows Monday night from 45 to 55.

&&

.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
As of 400 PM EDT Sunday...Strong upper level trough will cross
the area on Tuesday. Lots of clouds will keep temperatures mild
on Tuesday, highs around five to ten degrees below normal.
Temperatures aloft are even cooler which results in a bit of
instability, so have mentioned showers as well as thunderstorms
in the afternoon and evening. Cold air aloft means low wet bulb
zero heights so won`t be surprised to see some small hail in any
deeper convection. Have chance for showers mentioned early
Tuesday evening across our Northeastern zones but chances will
lessen overnight with upper level and surface ridging building
into the area.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 400 PM EDT Sunday...The extended portion of the forecast
looks wet and near normal for temperatures. It will not be
cloudy and rainy continuously, but weather pattern is active and
there will be several rounds of precipitation, tough to find a
dry day in the next week. Upper level flow is progressive and
fast with west to east flow. Shortwaves passing through upper
level flow will enhance chance for showers and thunderstorms.
Still tough to time these shortwaves, and have continued with
previous forecaster thinking of a model blend from day to day.
GFS and ECMWF continue to show a large upper level trough
developing to our west on Saturday, deep southerly flow develops
and brings some very moist air to the region. Temperatures will
start out slightly below seasonal normals then trend back
towards seasonal normals towards the end of the week.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
Through 18Z Monday...Mainly VFR through the period with
scattered showers and thunderstorms through early evening.
Shortwave pushing across the area this evening driving scattered
showers and thunderstorm activity across the area. No severe
weather is expected though a few of the more robust storms could
produce small hail, gusty winds into the 30-40 mph range,
enhanced low level turbulence and brief MVFR/IFR conds.
Coverage of storms to wane this evening and overnight with loss
of surface heating and as shortwave exits east. Winds west to
southwesterly 6 to 12 kts and occasionally gusty into the 15-20
kt range through sunset, abating to light overnight. After 12Z
Monday VFR continues, but with an increasing threat of showers
and thunderstorms once again as we approach the 18Z time frame.
Given this will occur toward the very end of this forecast cycle
have omitted specific mention at this point. Winds continue
light west/southwesterly 5 to 10 kts.

Outlook...

Monday Night: VFR. Chance SHRA...Slight Chance TSRA.
Tuesday: VFR. Chance SHRA...Slight Chance TSRA.
Tuesday Night: VFR. Slight Chance SHRA...Slight Chance TSRA.
Wednesday: VFR. Chance SHRA...Slight Chance TSRA.
Wednesday Night: VFR. Slight Chance SHRA.
Thursday: VFR/MVFR. Likely SHRA.
Thursday Night: MVFR. Likely SHRA...Slight Chance TSRA.
Friday: VFR/MVFR. Chance SHRA...Slight Chance TSRA.

&&

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

&&

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