129
FXUS61 KBTV 260728
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
328 AM EDT Fri Jun 26 2026
.WHAT HAS CHANGED...
As of 315 AM EDT Friday...
Added mention of small hail and gusty winds with thunderstorms
this afternoon, mainly from 11 am to 5 pm.
&&
.KEY MESSAGES...
As of 315 AM EDT Friday...
1. Widespread showers which moved through the region overnight
are coming to an end. Additional showers with embedded
thunderstorms are expected this afternoon, some may be strong.
2. Afternoon showers and thunderstorms will be possible both
Saturday and Sunday, especially across the higher elevations.
3. A round of showers and thunderstorms may occur late Tuesday
into Wednesday, followed by additional chances of thunderstorms
later in the week.
4. Hot and humid conditions will likely build into the region,
resulting in potential Heat Advisories in early July.
&&
.DISCUSSION...
As of 315 AM EDT Friday...
KEY MESSAGE 1: A warm front is lifting north across our region
and showers spread across the area associated with this feature.
Had a pretty widespread wetting rain overnight. The widespread
rain will be ending in the next few hours. Additional convective
showers with embedded thunderstorms are expected this afternoon
as a cold front pushes eastward across the forecast area.
Models continue to indicate surface based CAPE around 500-1500
J/kg, and 0-6km bulk shear to around 35 kts. Noticing some
clearing upstream on satellite, and this should move into our
area this morning helping to develop the surface based
instability for some thunderstorms to develop this afternoon.
The Storm Prediction Center has Marginal Risk (level 1 of 5) for
severe weather covering most of Vermont and a bit of northern
New York in the Champlain valley. The main threats from these
thunderstorms will be localized damaging winds and some isolated
large hail, have added enhanced wording to the forecast. Pwats
today will be lower than recent events only to an inch or inch
and a quarter which which will be unlikely to cause many
flooding concerns. Rainfall totals will generally range from two
tenths of an inch to an inch of rain. Locally higher amounts
may be possible under any thunderstorms.
KEY MESSAGE 2: After soaking rain, some river valley fog is
possible Friday night as dewpoints will remain elevated around
60 degrees. Into the weekend, broad upper level troughing will
keep shower chances each afternoon. Diurnally driven terrain
showers and embedded isolated thunderstorms will be possible
both Saturday and Sunday afternoons, mainly over the Adirondacks
and spine of the Greens. Best chances will be on Saturday.
These showers may drift briefly into the Champlain Valley or
eastern Vermont by the mid to later afternoons, but will likely
weaken as they become detached from better convergence and
mesoscale forcing. Rainfall with these showers will be light to
a few hundreths to a tenth under any more developed showers. Any
afternoon shower activity will wane after sunset with the loss
of diurnal heating. Temperatures will begin a steady warmup
leading into next week. Highs this weekend will rise from the
mid to upper 70s Saturday to the upper 70s to low 80s by Sunday.
Humidity will also linger with dewpoints in the low 60s,
keeping overnight lows relatively warm into the upper 50s to low
60s.
KEY MESSAGE 3: The weather details for the middle of next week
are becoming a little clearer. The consensus idea is that a
ridge roller dives southeastward from southern Canada into
northern New York and western Vermont. This timing appears to be
either late in the day Tuesday or Tuesday night. The air mass
would be quite juiced with regards to heavy rain potential with
PWAT surging well over 2 inches, and frequent lightning/loud
thunder could occur with ample elevated instability.
The track of this relatively small system certainly could shift
a bit west or east relative to the consensus, but overall at
least a portion of the region will likely see this system come
through. Note the upper level pattern looks fairly stagnant, in
which we sit on the northeastern periphery of a heat dome.
Potential for strong to severe thunderstorms with heavy rainfall
rates will be something to watch through the rest of the week.
KEY MESSAGE 4: Overall, the potential for major heat risk is
elevated for Wednesday and Thursday following a seasonably hot
day on Tuesday when highs should range through the 80s. The risk
is associated with expected greatly increased humidity (50-80%
chance of dew points being in the 70s during the daytime hours)
and hot temperatures (60- 80% chance in the Champlain and Upper
Valley highs will exceed 90), leading to heat index values at
least topping out in the mid and upper 90s in our valleys.
Confidence in the heat being impactful is higher on Thursday
than Wednesday, when the aforementioned ridge roller could
temporarily cool/stabilize the air in at least portions of our
region, such that temperatures struggle to recover and fail to
reach the current forecast (mid 80s to low 90s).
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Through 06Z Saturday...A mix of VFR and MVFR conditions are
present amidst a broad area of clouds and pockets of showers.
The largest area of showers in Vermont is shifting east of the
airspace at this hour, but a smaller area of showers affecting
MSS-SLK-PBG-BTV is only gradually shifting north of these sites.
Lightning has been within the vicinity at SLK, but overall risk
of thunder is low through 12Z. Expect ceilings will drive any
flight category changes through the next few hours and the
signals are somewhat mixed. It appears there is enough mixing of
low level air to keep cloud bases up/minimize low stratus, but
brief LIFR conditions cannot be ruled out as surface conditions
will be wet.
The most significant weather will tend to be around convection
favored from the 12Z to 15Z period as a mesoscale low pressure
area currently over Lake Ontario tracks across the middle of the
region (most likely affecting SLK, PBG, BTV, and MPV), followed
by scattered thunderstorms possible thereafter through about
20Z. Coverage of these afternoon thunderstorms will be fairly
limited by drier air, although a direct hit could lead to
impacts including gusty winds and small hail. Following the
showers and thunderstorms, light winds and clearing skies will
support quick development of fog. Have not mentioned it in the
TAF at this time, but soon after 00Z BR or FG could already
develop, especially at sites that see more rain during the
afternoon/early evening.
Outlook...
Saturday: Mainly VFR, with local MVFR possible. Slight chance
SHRA, Slight chance TSRA.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. Slight chance SHRA, Slight chance TSRA.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. Slight chance SHRA, Slight chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Neiles
DISCUSSION...Neiles/Kutikoff
AVIATION...Kutikoff
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