263
FXUS61 KBTV 181850
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
250 PM EDT Thu Jul 18 2024

.SYNOPSIS...
Quiet and dry weather conditions are expected the next couple days.
Some valley fog will be possible both tonight and tomorrow, with
seasonable nighttime temperatures in the 50s to lower 60s. A front
will approach from the north Saturday night and early Sunday, but
will wash out. This will produce only isolated to scattered shower
activity with the highest chances along the international border
before reinforcing the region with more dry and seasonable weather.
A series of weather disturbances will bring increasing rain chances
for the later half of next week.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
As of 249 PM EDT Thursday...The curl of an upper trough can be seen
to our north clearly on satellite. A few showers are propagating in
northwest flow beneath the trough axis, but these are light and few
in number. Decreasing thicknesses with the trough and dry air is
producing more refreshing weather than we have had in some time.
Surface high pressure will nose in overnight. Although there could
be pockets of stratus banked up against northwestern slopes, skies
should be mostly clear. Between how saturated the ground is and how
cool weather conditions tonight, one might think it`d be the perfect
night for fog. And it would be, except that the winds 500 feet above
the ground are still likely to be 10 to 15 mph. Forecast soundings
show potential mixing could still occur. For now, have kept the
previous forecaster`s valley fog with no changes. Overnight lows
should fall into the upper 40s across the Adirondacks and 50s across
the rest of the region, but perhaps still 60 at BTV.

A nice seasonable weather day is on tap Friday with mid 70s to lower
80s and mid 50s for dewpoints. High pressure will stretch out west
to east and a large trough will begin to carve itself out in
northern Quebec Province. This will turn our flow from west-
northwest to west-southwest. A subtle difference, but one that will
result in gradual warming. So overnight lows should mainly stay in
the 50s for most locations, with lower 60s in the broader Champlain
and St. Lawrence Valleys. Expect some fog in eastern Vermont river
valleys with more favorable conditions, but winds just off the
surface remain near Saranac Lake.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 250 AM EDT Thursday...Quiet weather is expected Friday night
into Saturday morning with high pressure remaining entrenched across
the North Country. A cold front will drop south out of Canada
Saturday afternoon which should help spark some scattered shower
activity across the region. Model soundings show some shallow
instability but a capping inversion around 15 kft is expected to
prevent any thunderstorms. With the parent low well north of the
International Border, shower activity along the frontal boundary
will weaken into the evening hours as the cold front shears apart.
Although we will see the passage of a "cold front", overnight lows
will remain mild Saturday night as cloud cover should prevent
radiational cooling.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 250 AM EDT Thursday...Sunday will be the nicest day of the
weekend, although the whole weekend is looking much better than
those of late. Following the frontal passage on Saturday, high
temperatures will be noticeably cooler with highs generally into the
70s although southern Vermont could see places hit the mid to
possibly even upper 80s. Dewpoints will remain in the 50s so it`s
going to feel downright pleasant outside. An isolated afternoon
shower cannot be ruled out but it;s nothing to really be concerned
about.

The aforementioned cold front will begin to lift back northward as a
warm front on Tuesday which will help increase rain chances as we
head into the middle of the upcoming week. By Wednesday, PWATs are
expected to surge back to the 1.5" to 1.7" range which could lead to
both some thunderstorm activity and the potential for heavy rain.
The good news is there isn`t any synoptic forcing to really get
anything organized outside of the frontal boundary lifting
northward. Taking a look at some of the ensemble data, some
locations could see upwards of an inch of rain late Tuesday into
Wednesday but the overall thinking is less than a half of an inch
for most locations. We will watch this closely but it doesn`t have
the makings of a flooding event at this time.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
Through 18Z Friday...Mainly VFR conditions outside potential for
patchy fog at KSLK/KMPV between roughly 05z and 11z. On one
hand, grounds are very moist and temperatures will be the
coolest they have been in weeks, but there remains 10 to 15
knot winds around 500 ft agl. Tweaked previous forecast timing
to match last night`s observations, but there remains
uncertainty in fog potential due to winds just off the ground.
Winds are out of the northwest between 7 and 12 knots with
gusts 16 to 22 knots at times. Winds become variable or terrain
driven overnight, and become northwest to west again after 12z.

Outlook...

Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Sunday: Mainly VFR, with local MVFR possible. NO SIG WX.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. Slight chance SHRA.

&&

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

&&

$$
SYNOPSIS...Haynes
NEAR TERM...Haynes
SHORT TERM...Clay
LONG TERM...Clay
AVIATION...Haynes