St. Albans, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

786
FXUS61 KBTV 191114
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
714 AM EDT Sat Jul 19 2025

.SYNOPSIS...
Today will feature mostly sunny skies with near normal
temperatures in the mid 70s to lower 80s and comfortable
humidity values. Clouds increase late in the day with scattered
to numerous showers and embedded thunder arriving overnight into
Sunday. A few stronger storms are possible late Sunday morning
into the early afternoon hours, with localized gusty winds,
frequent lightning and heavy down pours as the primary threats.

&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...
As of 438 AM EDT Saturday...Quick update this morning to
increase the areal coverage of fog, per obs and latest GOES-19
fog product. Fog has developed across portions of the Adirondack
Mtn Valleys and over parts of central/eastern VT. Rest of fcst
in good shape with fog lifting between 7 AM and 9 AM.

Previous discussion below:
GOES-19 fog product is showing some patchy fog develops acrs
portions of the Adirondack Valleys and eastern VT early this
morning, as temps cool back into the 40s to near 60F here in the
CPV. Patchy valley fog should burn off by 8-9AM with mostly
sunny skies prevailing before mid/upper lvl clouds develop this
aftn. Temps warm quickly into the mid 70s to lower 80s given the
dry airmass in place, resulting in comfortable humidity values.
Light trrn driven winds become south 5 to 10 mph today as sfc
high pres shifts to our east.

&&

.SHORT TERM /MONDAY/...
As of 230 AM EDT Saturday...Primary concern in the short term
wl be areal coverage of showers and thunderstorms tonight into
Sunday, along with the potential for localized strong to severe
storms. SPC has upgraded portion of our cwa into marginal/slight
risk for severe on Sunday, while WPC holds a day 2 marginal for
exceeding flash flood guidance. Given the fast movement of
activity associated with 700 to 500mb flow of 35 to 55 knots,
feel the threat for flash flooding associated with any
convective activity on Sunday is low attm.

The synoptic setup for tonight into Sunday is rather messy and
complex, as numerous embedded s/w`s are progged to move acrs our
cwa, which may produce plenty of clouds and limit instability on
Sunday. Initial s/w energy and waa develops this evening and
expands from west to east acrs our cwa overnight, which should
result in scattered showers with a few embedded rumbles. Did
note an axis of elevated instability with mucape values near
1000 J/kg over northern NY by 09z Sunday. For Sunday additional
s/w energy drops southeast associated with developing mid/upper
lvl trof and sharp cold front, however a convectively induced
vort over the central Plains this morning wl also race eastward
in the flow aloft and impact our central/southern cwa on Sunday
too. This could provide additional area of clouds/showers and
hold instability in the 300-600 J/kg range, per the GFS
solution and limit our stronger storm potential. HREF does
indicate sfc based cape values in the 1000-1500 J/kg range over
central/southern VT, with favorable 0 to 6 km shear in the 35 to
50 knot range. Sounding analysis does indicate some turning of
the llvl wind fields, especially in aligned south to north
valleys, like the CPV and lower CT River Valley, otherwise flow
is mostly unidirectional supporting linear segments as the
primary convective mode. The amount of clearing and instability
wl determine how robust the convection can become ahead of sfc
boundary late Sunday morning into the early aftn hours. By late
aftn/evening, primary threat for convection should be shifting
to our south and east, as much drier and cooler air develops on
brisk west/northwest winds.

Pw values in the 1.50 to 1.75" range and equilibrium levels
near 200mb supports tall storm structures capable of producing
very heavy down pours/high rainfall rates, but progged storms
motions of 25 to 30 knots should limit any flash flood threat.
We wl continue to monitor for the potential for training
convection, but given digging mid/upper lvl trof flow should
back to the west/northwest over time, preventing this potential.
Temps warm into the mid 70s to lower 80s on Sunday with a bump
in the humidity values. Much cooler and drier air filters into
the region on Sunday night into Monday. Temps are only in the
mid 60s to mid 70s on Monday with plenty of upslope clouds
likely acrs the higher trrn on north/northwest flow.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 230 AM EDT Saturday...Surface high pressure will build in for
Monday night, causing ideal radiational cooling to occur.
Temperatures look to fall into the 40s and 50s in most places though
the coldest hollows of the Adirondacks and Northeast kingdom may
reach the upper 30s. Surface high pressure looks to slowly move
across the region and to the east on Tuesday and Wednesday, bringing
two days of seasonably cool temperatures. A cold front approaches
the region on Thursday, but guidance still varies on the timing of
its passage. The current most likely scenario is its passage
sometime Thursday night and into the day on Friday, but a passage as
early as Thursday and as late as Friday night seem possible. The
front will bring some showers and likely some embedded
thunderstorms. Ahead of it on Thursday, the heat and humidity will
build back in with temperatures rising above seasonable normals and
dew points rising into the 60s to around 70. A cooler drier airmass
will move in on the backside but the change does not look to be as
dramatic as the one yesterday or the one coming Sunday.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
Through 12Z Sunday...Any lingering fog will lift within the next
hour or two and VFR conditions are expected to prevail through the
evening. Rain showers will move into the region later tonight. Most
of them should be light enough to not significantly reduce
visibilities, though the heaviest of them may be able to briefly
drop visibilities to MVFR or IFR. A couple embedded thunderstorms
are possible as well, though they will likely not contain strong
winds. Ceilings will lower once the rain arrives and they may drop
to MVFR by the end of the night. Winds will become southerly and
southwesterly during the day, though they should generally remain
around and under 10 KTs.

Outlook...

Sunday: Mainly VFR, with areas MVFR possible. Chance SHRA, Chance
TSRA.
Sunday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.

&&

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

&&

$$
SYNOPSIS...Taber
NEAR TERM...Taber
SHORT TERM...Taber
LONG TERM...Myskowski
AVIATION...Myskowski