750
FXUS61 KBTV 220637
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
237 AM EDT Mon Jun 22 2026
.WHAT HAS CHANGED...
As of 237 AM EDT Monday...
No significant changes associated with this forecast package.
&&
.KEY MESSAGES...
As of 237 AM EDT Monday...
1. Light to moderate rainfall is expected to develop central
and southern Vermont this afternoon, but the potential for any
flooding is low.
2. An approaching cold front will bring a sharp increase in
shower and thunderstorm chances for the end of the week with
unsettled conditions continuing into the weekend.
&&
.DISCUSSION...
As of 237 AM EDT Monday...
KEY MESSAGE 1: GOES-19 mid lvl water vapor imagery shows decaying
convective induced vort and associated sfc low pres over the Ohio
Valley moving toward the Mid Atlantic/NE CONUS. Sfc low pres is
progged to track from the Ohio Valley into Southern New England by
tonight, while our cwa stays on the cooler/stable side of this
system. The lack of instability acrs our cwa, should minimize
rainfall rates this aftn/evening and result in a low probability of
any flooding. In addition, flow aloft is progressive west to east,
which should keep precip moving. As southern stream s/w energy lifts
toward southern NY this aftn, expect an expanding area of light to
moderate rain to develop over the High Peaks into central/southern
VT. The best 700-500mb lift and deep layer moisture (850-500mb) wl
be located over Rutland/Windsor counties associated with northern
side deformation zone. Expected a sharp north to south precip
gradient acrs our cwa, which is similar to a winter-time unphased
and progressive Ohio Valley low pres system.
HREF shows 60-90% prob of 24 hour rainfall >1.0" acrs
Rutland/Windsor counties, while 30% or less for rainfall >2.0". The
HREF total mean precip is in the 1.25" to 1.50" range mostly along
and south of Route 4, which looks a little high given dynamics and
available moisture with this system, as pw values approach 1.25".
Thinking qpf around 1.0" south, to 0.10 to 0.30" along a SLK to BTV
to 1V4 line and a tenth or less near the International Border. This
highlights the sharp north to south precip gradient expected and
have pops accordingly. Given recent rainfall hydro wl need to be
watched, but feel pretty confident no issues in our cwa through
tonight. Given expanding cloud cover and rain developing by this
aftn, have trimmed 1 to 3 degrees off NBM with highs mostly in the
upper 60s to mid 70s, warmest north and coolest south.
Tonight initial s/w energy quickly shifts off the New England Coast
and subsidence aloft builds into our cwa as weak elongated low pres
is located over SNE. Have continued with some lingering showers thru
06z, but feel decreasing moisture profiles should limit areal
coverage of precip aft midnight. Some patchy fog is possible in
areas that can decouple and clear out with lows in the upper 40s to
upper 50s. On Tuesday, northern stream s/w energy approaches the
International Border area btwn 21-00z, but moisture/instability
parameters are weak. Thinking dynamics and northwest upslope flow,
wl be enough to produce scattered showers, especially northern Dacks
into the mtns of central/northern VT. Areal coverage should be
mostly confined to the trrn and parts of the NEK on Tues. Did trim a
degree or two from progged high temps with values mostly in the 70s
to near 80 locally in the CPV.
Our next northern stream mid/upper lvl trof and associated height
falls arrives late Thurs. Weak 1010mb sfc low pres is progged over
the central Great Lakes, while a warm frnt/moisture surge is lifting
acrs the Ohio Valley into the NE CONUS on Thurs aftn. The
combination of warm frontal lift/moisture and s/w energy riding
along gradient should produce a period of showers and embedded
showers late Thurs/Thurs night. Crnt guidance indicates best
instability wl stay south of our cwa thru Thurs, along with the
highest pw values. We wl keep pops in the chc range for Thurs and
increase them toward likely Thurs night. Highs wl be near normal
both Weds and Thurs with values in the mid 70s to lower 80s with
lows lower 50s to lower 60s.
KEY MESSAGE 2: Low pressure crossing the Great Lakes will advect in
moisture and warmth to northern New York and Vermont ahead of a warm
front Thursday night, with lows both Thursday and Friday nights will
be mild in the 50s and lower 60s. Seasonable highs in the 70s and
lower 80s are expected on Friday afternoon. Blended guidance has
trended slightly in the direction of global deterministic solutions,
therefore the main swath of steady rain and embedded thunderstorms
is looking like it comes through Thursday night as low pressure
grows closer to the forecast area while passing into Quebec. Precip
chances 70-90% are forecast Thursday night, then on Friday, low
pressure will speed across Quebec towards the Canadian maritimes,
dragging both a warm front and a weak cold front through the
forecast area, keeping the region showery with afternoon
thunderstorms. Highest precip chances 55-95% are focused along the
international border, closest to low pressure, as well as in the
mountains with orographic assistance. A half an inch of rainfall in
24 hours Thursday night through Friday looks most likely across the
Adirondacks and northern Vermont, though probabilities of 1 inch or
more within a span of 24 hours are lower, around 15-45%. That being
said, anywhere that we see convective showers and thunderstorms,
especially training storms, could see localized higher amounts than
expected. We`ll be keeping an eye on this pattern through the week
given recent saturation of soils and increased runoff potential.
Then on Friday night we expect a dramatic decrease in shower chances
and coverage as the low pressure rushes east into the Canadian
maritimes and drier air filters into northern New York and Vermont.
Cyclonic flow will likely linger behind the system, keeping some
shower chances in place over at least a portion of the weekend
depending on how fast ridging can build back in, with highs each
afternoon in the 70s and lower 80s.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday...Recent rainfall, clear skies, and light winds
early this morning is a recipe for radiational fog, and site PBG is
already reporting visibilities ranging from 1 to 3 miles and
occasional ceilings around 200-400 feet above ground level. We
anticipate sites SLK, MPV, and EFK will join them over the next few
hours, though confidence is decreased by the increasing cloud cover
ahead of our next round of precipitation. However, confidence is
increased at SLK by its temperature already plummeting into the 40s
as of 06Z Monday. Thinking vis and cigs will go to IFR levels at
these four sites on and off through 14Z Monday, and other sites may
have vicinity fog approaching runways. After 12z Monday, southerly
winds will increase to 5-15 knots, and rain with vis 3-6 miles and
MVFR level ceilings will gradually overspread the region from the
south after 18z Monday. After 00Z Tuesday, ceilings may even fall to
IFR levels at RUT.
Outlook...
Tuesday: Mainly VFR, with local IFR possible. Slight chance SHRA.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. Chance SHRA, Slight chance TSRA.
Thursday Night: Mainly VFR, with areas MVFR possible. Likely
SHRA, Slight chance TSRA.
Friday: MVFR/IFR conditions possible. Definite SHRA, Chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Taber
DISCUSSION...Storm/Taber
AVIATION...Storm
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