544
FXUS61 KBTV 071852
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
252 PM EDT Fri Aug 7 2026
.WHAT HAS CHANGED...
As of 252 PM EDT Friday...
Increased confidence in rain next Thursday.
&&
.KEY MESSAGES...
As of 252 PM EDT Friday...
1. Intervals of scattered showers and thunderstorms with warm,
humid conditions will continue through much of the weekend.
2. A brief period of lower humidity and dry conditions later
Sunday into Monday morning will end with increasing chances of
showers and thunderstorms later Monday.
3. Seasonable conditions are anticipated next week with
additional chances for showers and thunderstorms as well as
gradually decreasing temperatures.
&&
.DISCUSSION...
As of 252 PM EDT Friday...
KEY MESSAGE 1: Isolated to scattered showers with a couple of
thunderstorms remain on track for this evening into the overnight
hours. For late this afternoon and evening, it appears our setup is
reminiscent of yesterday with pulse storm potential. However, subtle
differences will limit the thunderstorm threat. Instability over the
Adirondack region is less robust, and so the ability for stronger
convection will be limited by these initial weaker updrafts.
However, increasing cyclonic flow as an upper level wave over the
eastern Great Lakes gets slowly pushed towards our region will help
generate more showers with time, peaking during the early morning
hours and across northern portions of Vermont. With such weak
forcing including lack of a well defined front or low pressure
system, precipitation amounts will continue to be quite
spatially variable. Activity will generally shift to the
northeast with time, and pockets of heavier rainfall (~0.25 -
0.5" with localized 1" amounts) will tend occur through tomorrow
morning. Some locations, probably in southern portions of
Vermont, again should see little or no rain.
For Saturday, there are again some mixed signals in terms of the
convective evolution. Each of the last couple of cycles, machine
learning guidance has been somewhat bullish on potential for some
stronger thunderstorms. Consensus shows higher probabilities both
south and east of our region; the latest Day 2 Storm Prediction
Center severe risk does highlight the mid-Atlantic region again
following today`s stronger storms in that area as well. That being
said, generally thunderstorm probabilities are roughly as high in
our region as towards the south, with regionally greatest chances in
northeastern Vermont and lowest chances in the southern St. Lawrence
Valley and southern Vermont. Representative forecast soundings in
St. Johnsbury during the early evening show MLCAPE of around 1500
J/kg (moderately high CAPE) and effective shear of 10-15 knots (low
wind shear), so the environment looks marginally supportive of pulse
thunderstorms with mainly typical thunderstorms and a rare stronger
wind gust possible.
Following yesterday`s anomalous moisture, precipitable water will be
a bit lower tonight when it surges with the wave coming through
(about 1.7" to 1.9"), and fall further tomorrow (about 1.5" to
1.7"). So while a marginal (level 1 out of 5) risk of flash flooding
continues associated with heavy rainfall rates in thunderstorms,
think the footprints of 2" + that we saw yesterday are less likely.
With meager instability available ahead of a final round
of scattered showers moving through overnight Saturday into the
day on Sunday, risk of impactful weather diminishes further as the
weekend wears on. As the associated weak surface front passes
to our east, sharply drier, refreshing air will return during the
second part of the day.
KEY MESSAGE 2: Tranquil, seasonably warm conditions from late Sunday
into Monday will prevail as a narrow axis of deep layer ridging
zips into and then out of our region to be replaced by a
prefrontal trough Monday evening. Most of the impacts from this
trough and the following cold front will follow Monday night,
but overall the threat of showers and thunderstorms will ramp up
towards evening, particularly in northernmost portions of New
York where both rain and thunder chances are highest through the
afternoon hours. Stronger storms currently look unlikely with
only modest instability and shear, but we`ll have to monitor any
trends in the data if they deviate from the current thinking.
KEY MESSAGE 3: A cold front is expected to cross the region Monday
night, bringing an increased chance (45-85%) of precipitation to
northern New York and Vermont, including some overnight embedded
thunder. Temperatures will be on the milder side throughout the
night, remaining at or above the mid 50s to mid 60s. Tuesday could
also be a showery day with embedded thunder (precip chances 15-55%)
under modest cold air advection and seasonable temperatures in the
mid 70s to mid 80s. Mid week will feature a period of 15-55% chance
of precipitation and seasonable temperatures (highs mid 70s to lower
80s, lows 50s and lower 60s). Then, longwave troughing returns late
week, bringing a resurgence of higher shower and thunderstorm
chances on Thursday afternoon plus highs falling into the 70s for
most both Thursday and Friday.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Through 18Z Saturday...Without sufficient forcing, a couple spot
showers or storms will be possible this afternoon on eastern slopes
of the Adirondacks along the Lake Champlain lake breeze. Tonight,
troughing will lift northeast, making for some nighttime showers and
thunderstorms. Most likely period for this will be 06Z through 10Z
Saturday, which could reduce visibilities briefly in precipitation.
Anywhere that sees some precipitation could have mist or fog popping
up overnight tonight, particularly in southwestern areas that have
earliest clearing on Saturday morning. These southwestern sites
would be MSS, SLK, and RUT, though mist and fog at any site is not
out of the question depending on where rain occurs today. Most
likely period of fog and low clouds will be around 06Z through 14Z
Saturday at SLK, MPV, RUT, and EFK, though MSS will need to be
closely watched, especially if it gets rain today, though that looks
unlikely. Winds over the next 24 hours remain light and variable,
though they should increase slightly out of the south throughout the
night and into Saturday.
Outlook...
Saturday Night: VFR. Chance SHRA, Chance TSRA.
Sunday: VFR. Chance SHRA.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. Chance SHRA, Chance TSRA.
Monday Night: Mainly VFR, with local IFR possible. Likely SHRA,
Slight chance TSRA.
Tuesday: MVFR/IFR conditions possible. Chance SHRA, Slight chance
TSRA.
Tuesday Night: VFR. Slight chance SHRA.
Wednesday: VFR. Slight chance SHRA, Slight chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Kutikoff
DISCUSSION...Storm/Kutikoff
AVIATION...Storm
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