087
FXUS61 KBTV 051747
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
147 PM EDT Sun May 5 2024

.SYNOPSIS...
Widespread rainfall will occur today though it will be light enough
to prevent a flooding threat. Temperatures will remain cool with
highs only in the upper 40s to mid 50s. High pressure will build
into the region for the start of the work week and bring dry and
mild weather. Rain showers will arrive for mid and late week.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 139 PM EDT Sunday...There`s a tiny tongue with little
precipitation nosing into Essex County New York and now into the
Champlain Valley, but more rain remains upstream. The forecast
thus remains in solid shape.

Previous Discussion...Cloud cover is currently spreading across
the region from southwest to northeast out ahead of rain that
will arrive later tonight. The rain will overspread northern New
York in the next couple hours and it will overspread Vermont by
mid- morning. Temperatures have been slow to drop tonight,
particularly in the Champlain and St. Lawrence Valleys, due to
southerly flow and increasing cloud cover. Temperatures there
have been holding in the mid 50s to low 60s. Once the rain
arrives, evaporational cooling will help temperatures drop back
into the mid-50s. Cool moist southeast flow off the Atlantic is
keeping areas east of the Greens much cooler, with temperatures
there in the mid-40s.

Rain showers will prevail for much of the day. Despite the
relatively long-duration rain, rainfall rates will be light so
generally only between one and two thirds of an inch will fall.
Therefore, no river flooding is forecast. Some elevated instability
may develop over northern New York this afternoon where a few
heavier convective showers and isolated thunderstorms are possible.
Temperatures will not move very far during the day so highs should
generally be in the upper 40s to mid-50s. A southerly low-level jet
will pass over the region and it will cause some gustier winds and
channeled flow in the Champlain Valley. Gusts will reach between 15-
25 mph but gusts up to 30 mph are possible on Lake Champlain. The
steady rain will move out of the region later in the afternoon but
some showers will linger into the night. A following cold front will
move through later tonight and bring another round of more organized
showers, mostly to northern areas. Behind the front, moist northwest
flow will should cause some rain showers on Monday, particularly in
the upslope areas of the Greens. The rain showers will diminish in
the afternoon. There is not much of an airmass change behind the
front so despite northwest flow, some breaks in the clouds will
allow for efficient mixing and temperatures should generally rise
into the 60s and low 70s.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY/...
As of 351 AM EDT Sunday...Dry weather will prevail through this
period as ridging builds over the region. Monday night will see
optimal raditional cooling under clearing skies and light winds.
Note that moisture profiles indicate patchy fog developing in the
favored valley locations, so have added that to the forecast. Lows
will generally be in the 40s, though some of the usual cold spots
could drop into the upper 30s. Tuesday will feature ample sunshine,
with any fog dissipating by mid morning. Fair weather cumulus will
develop during the afternoon, but shouldn`t be widespread enough to
block much sunshine. Highs will range from the mid 60s to the mid
70s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 351 AM EDT Sunday...Precipitation chances will increase Tuesday
night into Wednesday as a low pressure system slides by just to our
south. This will be the first in a series of systems that will
affect our region through the latter half of the week as an upper
trough tries to become established across the eastern CONUS. The
timing of any upper troughs and how much phasing is able to occur
varies from model to model and run to run, so can`t definitively say
which one period might have the most shower activity or which might
trend drier. However, can say that there will be a gradual cooling
through the week, with Friday and Saturday only topping out in the
upper 40s to mid 50s.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Through 18Z Monday...Rain continues across the region. Mainly
MVFR ceilings between 1400-2200 ft agl are being observed and
visibilities mainly range between 3 and 7 SM in moderate rain.
Anticipate brief reductions with somewhat heavier precipitation
at KMSS and KSLK through 19z and 21z respectively, but this
should weaken approaching remaining terminals. The initial batch
of precipitation will slide east of the region between 23z and
01z Monday. Upstream, noting some ceilings around 300-900 ft
agl, but thinking it will primarily be as another boundary
shifts through between 04z and 13z that prevailing IFR ceilings
could occur. Winds are mostly out of the south at 7 to 13 knots
with a few gusts 16 to 20 knots. These should continue through
00z, and then subside. After the boundary shifts east by 13z,
winds should trend southwest to northwest around 5 knots.
Ceilings should quickly improve beyond 15z Monday.

Outlook...

Monday Night: VFR. Patchy BR.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. Chance SHRA.
Wednesday: VFR. Definite SHRA.
Wednesday Night: Mainly MVFR, with local IFR possible. Slight
chance SHRA.
Thursday: Mainly MVFR, with areas VFR possible. Likely SHRA.
Thursday Night: Mainly MVFR, with local IFR possible. Likely
SHRA.
Friday: Mainly MVFR, with areas IFR possible. Likely SHRA.

&&

.MARINE...
South winds have been trending towards 20 to 25 knots over the
course of the morning and early afternoon. It is expected that
sustained winds to 25 knots, especially across the broad lake
will become more persistent late this afternoon and evening. A
Lake Wind Advisory is in effect, and waves up to 4 feet will be
possible. After 10 PM or so, winds should begin to subside
across the lake.

&&

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

&&

$$
SYNOPSIS...Myskowski
NEAR TERM...Haynes/Myskowski
SHORT TERM...Hastings
LONG TERM...Hastings
AVIATION...Haynes
MARINE...