Colchester, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

639
FXUS61 KBTV 201122
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
722 AM EDT Sun Jul 20 2025

.SYNOPSIS...
Showers and embedded thunderstorms are expected across the North
Country today. A few stronger storms with gusty winds, localized
heavy down pours and frequent lightning are possible, especially
across central and southern Vermont. Temperatures under mostly
cloudy skies will warm into the 70s to near 80. Much cooler and
drier air returns tonight and continues through early this upcoming
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 238 AM EDT Sunday...Forecast challenge today is showers with
embedded thunder timing and areal coverage, followed by potential
for a few stronger/severe storms. SPC continues marginal/slight for
our central/southern VT areas, which looks reasonable based on
frontal position and progged instability. Still have concerns with
regards to amount of clearing as latest soundings show plenty of
moisture thru a deep layer, which is also supported by latest GOES
19 IR satl imagery.

Crnt sfc analysis shows a convectively induced area of low pres over
central MI, with a cold frnt draped just north of the International
Border early this morning, while a warm frnt with a few showers is
lifting acrs northern VT. The so called warm sector is very messy
with abundant clouds, which may limit instability acrs
central/southern VT today, along with potential for svr storms.
However, guidance conts to show a sharp instability/thermal gradient
developing, along with good sfc convergence with boundary acrs our
cwa today. Sfc based CAPE off the HREF and latest CAM guidance still
indicates an axis of 1000-1500 J/kg, while 0 to 6 km shear is 35 to
50 knots acrs our central/northern cwa. The best interaction of
shear/instability conts to be acrs central/southern areas this aftn,
where SPC conts the marginal/slight risk for severe. Crnt thinking
is a few isolated svr storms are possible with wind as the primary
threat. Given the tall cape profiles and EL near 200mb, a few
stronger updrafts wl be capable of hail, but coverage wl be limited.

Little has changed with regards to our potential for localized heavy
rainfall and limited potential for exceeding flash flood guidance.
Pw values are still in the 1.50 to 1.75" ahead of boundary, while
warm cloud depths are in the 10,500 to 11,500 range, supporting
localized heavy down pours. Sounding analysis does show some
potential for back building/training convection along the boundary,
with individual storms moving east at 25 to 30 knots, while the
boundary slowly shifts south at 5 to 10 knots. This general idea
should limit the flash flood threat acrs our cwa today, but we wl
cont to monitor closely. Highs generally in the 70s to lower 80s, as
clouds wl limit sfc heating.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
As of 238 AM EDT Sunday...Mid/upper lvl trof wl be directly overhead
on Monday, before lifting out on Tuesday. 1020mb Canadian high pres
wl be building into our cwa on Monday into Tuesday with much drier
and cooler conditions anticipated. Lingering moisture in the trof,
combined with north/northwest upslope flow wl produce a few fair wx
cumulus clouds acrs the trrn on Monday with temps in the mid 60s to
lower 70s, supported by progged 850mb temps in the 4-6C range. A
cool night is anticipated on Monday night/Tues morning with lows
upper 30s to near 60F, warmest near Lake Champlain. Tues wl feature
plenty of sunshine and temps warming back into the 70s with
comfortable humidity values.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 218 AM EDT Sunday...Surface high pressure pushes off to the
east for Wednesday and Thursday, causing a warming trend. Highs look
to reach the upper 80s to lower 90s by Thursday. Humidity will be
increasing as well, with dew points reaching the 60s to around 70 on
Thursday. Models have converged on a later passage of the cold
front, so the day Thursday looks mostly dry and hotter. The cold
front now looks to pass through Thursday night or during the day
Friday, bringing scattered showers and possible thunderstorms. Any
severe potential would depend on the timing of the passage. The
flash flood potential currently does not look overly high, though
that will still need to be watched as the models converge on a
solution. Cooler and drier air move into the region on the backside
of the front, but the airmass change will not be as noticeable as
the one happening tonight. Temperatures look to remain above
climatological normals behind the front.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
Through 12Z Monday... An area of rain showers will slowly move south
during the day today associated with a cold front. Some embedded
heavier showers are possible and could briefly reduce visibilities
to MVFR, though a vast majority of the rain will be too light to
cause significant visibility reductions. Thunderstorms could develop
in southern Vermont so they are possible at RUT during the early and
mid afternoon. These could briefly cause IFR visibilities and gusty
winds from erratic directions. Precipitation moves out by evening
and dry conditions persist tonight. A period of MVFR ceilings is
expected after the front moves through. They could briefly fall to
IFR at SLK or MSS. Ceilings should gradually rise during the evening
and most should be VFR by late in the night. Winds will generally
change from variable to northwesterly once the front moves through.
Winds should generally stay around and under 10 KTs, except at BTV
and PBG where they could gust to 20 KTs behind tonight.

Outlook...

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.
Wednesday Night: VFR. Slight chance SHRA.
Thursday: Mainly VFR, with local MVFR possible. Chance SHRA,
Slight chance TSRA.

&&

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

&&

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