067
FXUS61 KBTV 280447
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1247 AM EDT Fri Jun 28 2024

.SYNOPSIS...
A cool and clear night with some patchy valley fog is anticipated
tonight, before a beautiful Friday is expected with plenty of
sunshine and comfortable temperatures. Unsettled weather returns on
Saturday afternoon into Sunday, along with breezy south winds.
Some isolated heavy rainfall can`t be ruled out for Saturday.
Next week will see a warming trend as high temperatures return
to the 80s to start off July.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 1242 AM EDT Friday...Sfc high pres continues to build into
our fa this morning with clearing skies and light winds. This
has resulted in ideal cooling conditions with SLK already down
to 39F. So have lowered the low to 35 or so at SLK while making
some minor tweaks elsewhere. Also, have noted some fog
development on webcams at Old Forge, so the idea of localized
fog/br toward sunrise in the deeper valleys of the Dacks looks
reasonable. No significant changes made to fcst.

PREVIOUS DISCUSSION...A late September-like negatively tilted
H5 trough is swinging through the area, helping to spark some
widely scattered sprinkles or light showers across the
Adirondacks, with even some steadier showers out towards the Tug
Hills. No weather impacts are expected, but noted the increase
in cloud cover as unseasonably strong cold air advection
continues. SPC RAP mesoanalysis shows +11 to +13C 925mb
temperatures being advected into the region, which equates to
the 10th to 25th percentile of SPC sounding climatology for the
Albany, NY upper air site. So aside from making minor tweaks to
the PoPs (15-20 percent across northern NY) and sky cover
through sunset, forecast remains very much on track. See
previous discussion below.

Cold front is finally moved out of our area and with that some
weak lingering rain showers move out of Eastern VT. High
pressure is moving in this evening and will settle over the
region tomorrow. Tonight will see some chilly weather as
overnight lows will be in the 40s with higher elevations in the
30s. Some overnight fog in the favored valleys can`t be ruled
out as well, but will be short lived if it does materialize.

Friday looks be quiet day with plenty of sunshine and day time highs
in the upper 60s to mid 70s,low humidity and light winds around the
region. Friday night will see the high pressure begin to retreat
ahead of the next system as overnight winds begin to pick up from
the south, mainly across the St. Lawrence and Champlain Valleys. New
York and Western Vt can expect showers to move into the area during
the predawn hours as well. Overnight lows will be 50s and 60s.

&&

.SHORT TERM /SATURDAY NIGHT/...
As of 244 PM EDT Thursday...A 50 knot southwesterly low-level jet
will move directly overhead Saturday afternoon into Saturday
evening, as our area is squeezed between high pressure to our east
and a low lifting to our north. With the resultant warm air
advection on southwesterly winds, a temperature inversion will
develop in the 850 to 950 mb layer, which will prevent the strongest
momentum air from mixing to the surface in lower elevations.
Nonetheless, expect a gusty day with south/southwest wind gusts 20
to 30 mph for most locations. Higher elevations (above 2500 ft) will
gust higher, potentially 45+ mph. The Champlain Valley will also see
stronger winds in the 25 to 35 mph range as flow is channeled
up the valley. Peak wind gusts will be observed Saturday
afternoon/early evening just before the onset of rain. Once
steady rain moves into the area, winds will diminish slightly as
the rain stabilizes the air. Latest thinking on the timing for
arrival of steadier precipitation will be Saturday afternoon for
northern NY, and late afternoon/early evening for VT. However,
some earlier scattered showers are possible before the arrival
of the steady precipitation. Given the low-level inversion,
instability will be marginal if any, and thus have kept mention
of thunderstorms out of the forecast for Saturday. However,
ingredients are favorable for some heavy rainfall overnight.
Precipitable water values climb to around 2.0 inches, which is
around 200% climatological normal. In addition, deep warm cloud
depths of over 12 kft will increase precipitation rates, though
lack of instability will temper heavy rainfall potential. At
this point, it appears system will be just progressive enough to
preclude any widespread training threat, though some isolated
areas may have multiple heavy rain showers move overhead and
thus may see some ponding of water in poor drainage areas.
Current Excessive Rainfall Outlook from WPC for Saturday has our
forecast area outlined in the Marginal Risk. Will be watching
things closely, but not expecting widespread issues at this
point. Storm total amounts for Saturday through Saturday night
will be in the 0.5 to 1.0 inch range.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 244 PM EDT Thursday...Steady rain will come to an end Sunday
morning, but showers will continue thanks to a series of fronts that
will move through during the day. As the fronts/troughs move
through, will see decreasing moisture and thus potential for any
moderate to heavy rain within showers will be lessening. However,
steepening low and mid-level lapse rates will result in some
marginal instability, though depth of moisture and instability will
be relatively shallow. Thinking we will see a few embedded
thunderstorms during the day within the rain showers, though limited
instability will temper severe potential.

Once the final cold front sweeps through late Sunday, will be in for
a drier start to the work week as expansive high pressure builds in
from the west. Highs in the 70s/low 80s with dewpoints generally in
the 50s will feel quite refreshing and should be a beautiful stretch
of weather overall. A gradual warming trend can be expected going
into midweek. The next chance for showers will be in the
Wednesday/Thursday timeframe.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Through 06z Saturday...VFR conditions expected at all taf sites
for the next 12 to 24 hours as sfc high pres is building
directly overhead. Given the 1 degree spread at SLK and crnt
temp at cross over value, expect some periods of fog and
associated IFR vis is possible btwn 07-11z. Feel the potential
is in the 30-40% range, so have utilized a tempo group to
highlight the potential, otherwise light and variable winds will
become south 4 to 8 knots toward 00z this evening.

Outlook...

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

&&

.MARINE...
Unseasonably strong winds are expected on Saturday when a Lake
Wind Advisory will be needed for Lake Champlain. South winds
may exceed 25 knots by daybreak and may be be above 30 knots on
the broad lake at times during the day. Rough waves could
develop quickly. Wave heights on the broad lake and inland sea
may build into the 3 to 5 feet range briefly Saturday.

&&

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

&&

$$
SYNOPSIS...Verasamy
NEAR TERM...Taber/Verasamy
SHORT TERM...Duell
LONG TERM...Duell
AVIATION...Taber
MARINE...Kutikoff