076
FXUS61 KBTV 062320
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
720 PM EDT Mon Jul 6 2026
.WHAT HAS CHANGED...
As of 248 PM EDT Monday...
No meaningful changes at this time. Aside from a few light
showers across northernmost Vermont and New York this afternoon,
weather remains dry and quiet across the area through midnight.
&&
.KEY MESSAGES...
As of 248 PM EDT Monday...
1. An area of rain showers will expand into southern portions
of Vermont and Adirondacks with light rainfall expected through
Tuesday.
2. Showers and thunderstorms are likely Thursday afternoon/night.
3. A cold front moves through Friday morning.
&&
.DISCUSSION...
As of 248 PM EDT Monday...
KEY MESSAGE 1: A large positively tilted trough over the Great Lakes is
inducing a weak surface low pressure system with mid-level
circulating tracking across western New York tonight and it
will slide eastward into southern New England by morning. On the
cool side of the boundary, there will be a sharp edge of clouds
and showers. The latest model guidance has settled on southern
Vermont being within this shield of light rainfall, likely in
the 0.25" to 0.5" range. This rain may consist of briefly
heavier elements, as showers overrun the boundary from the
juicier air mass to the south. Meager and shallow instability
will be present so we do not expect any thunder. As one goes
northward into central Vermont, a shorter period of showers can
be expected with low chances of even 0.1" of total rainfall.
Much of northern New York and northern Vermont will see no
precipitation. In fact, skies will be variably cloudy to mostly
sunny by later in the day Tuesday.
KEY MESSAGE 2: Following another very quiet weather period Tuesday
night through Thursday morning, our next round of active weather
will begin during the day Thursday. The ECMWF Extreme Forecast Index
does not show any signals in CAPE and shear for this event being
particularly noteworthy in spite of heat and humidity in place ahead
of a cold front - heat index values could peak in the lower 90s in
the deeper valleys. In referencing some deterministic model
guidance, it looks like a shortwave passing across the mid-
Atlantic states out ahead of this front could interfere with the
moisture feed northward into our region, but also may be
separated enough in space/time to not make a difference in our
convection. It looks like the moisture feed with a channel of
anomalous PWAT stretched along the boundary will consist of
modified southern Pacific Ocean moisture without the addition of
Gulf or Atlantic moisture, reducing the residence time of the
potential heavier rainfall rates. Accordingly, at this time we
aren`t seeing any signals for excessive rainfall despite
ingredients for at least briefly heavy rainfall with some of the
likely thunderstorm development.
While the upper level forcing will not be particularly strong, but
the track of weak surface low pressure and the associated belt of
stronger westerly winds appears to line up well for northern New
York and Vermont for a risk of strong thunderstorms and perhaps a
severe thunderstorm or two during the afternoon and especially
evening hours based on the consensus timing. Would expect at least a
marginal severe thunderstorm risk will be introduced from the Storm
Prediction Center moving forward. Noted that the machine learning
thunderstorm probabilities from the GEFS shows a regional maximum
across northeastern New York (around 70% chance). Convection across
southern Canada will shift south and eastward as the cold front
moves eastward, with a couple of boundaries pushing through to
eventually end the potential for showers on Friday. The risk of
thunderstorms, given only modest instability (MUCAPE in the 1000-
1500 J/kg range) driven by diurnal heating and height falls with the
incoming weak trough, should diminish overnight along with potential
for any localized flash flooding as drier air works in aloft.
KEY MESSAGE 3: A cold front will sweep through the CWA Friday morning,
bringing drier and seasonable temperatures to the region. Temperatures
on Friday and Saturday will be in the upper 70s or lower 80s for most
of our area. Similar to Thursday, we will see a chance of thunder and
some widespread rain along the front on Friday. Temperatures look to
rebound slightly for the second half of the weekend and beginning of
next week.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
Through 00Z Wednesday...Generally quiet aviation conditions are
expected with relatively little change over the next 24 hours.
Outside a few mid-level cumulus near KEFK, there are mostly
high clouds at or above 20000 ft agl. Southeast winds overnight
will be around 5 knots, but locally faster at KRUT around 7-10
knots. High clouds will track east with the St. Lawrence Valley
clearing out, and guidance indicates some fog potential at KMSS.
Since it`s one of the less favored, decided to hold it to 3SM
in a TEMPO from 06z-10z. Looking more closely at KRUT, the
potential for LLWS appears lower and removed it. Although winds
at 2000 ft agl will approach 25-30 knots, surface winds will
stay elevated enough that it could be bumpy, but doesn`t meet
criteria. Showers are expected near KRUT, mainly between 09z and
13z, but did use PROB30s on either end due to some timing
uncertainty. Lowering ceilings to 2500-4000 ft agl are expected
at KRUT as precipitation moves in. Remaining TAF sites will
likely avoid any rain and may just observe some lowering
ceilings past 13z.
Outlook...
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. Chance SHRA, Chance TSRA.
Thursday Night: Mainly VFR, with areas MVFR possible. Likely
SHRA, Chance TSRA.
Friday: Mainly VFR, with local IFR possible. Likely SHRA, Chance
TSRA.
Friday Night: VFR. Slight chance SHRA.
Saturday: VFR. NO SIG WX.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Kutikoff
DISCUSSION...Kutikoff/Langbauer
AVIATION...Haynes
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