St. Johnsbury, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

095
FXUS61 KBTV 042327
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
727 PM EDT Sat Jul 4 2026

.WHAT HAS CHANGED...
As of 259 PM EDT Saturday...

Air quality impacts no longer expected today/tonight.

&&

.KEY MESSAGES...
As of 259 PM EDT Saturday...

1. Showers and an isolated thunderstorm will gradually wind
down by sunset in southern portions of our region.

2. Seasonable and dry conditions early in the week. We`ll be
watching the northward extent of an area of heavy rain over
southern New England, which could come far enough north to
affect southern portions of Vermont.

3. Warm and somewhat humid for mid and late next week with a
couple shower chances.

&&

.DISCUSSION...
As of 259 PM EDT Saturday...

KEY MESSAGE 1: A very weak disturbance aloft well to our west coupled
with a sharp moisture gradient across northern New York and northern
Vermont is promoting a southward shifting area of showers today
along a surface cold front. The front is more of a dew point front,
with sharply drier air lagging a few hours but it is on its way with
refreshing air (dew points approaching 50 degrees) incoming on
breezy northerly winds.

The showers south of the boundary are producing a couple of
thunderstorms as of this hour. The chance of a thunderstorm
remains low but non-zero through this evening, although the
risk area will continue to shrink towards the south. Thankfully
for outdoor activities, even when showers grow tall enough to
produce lightning, storms will be quite weak given an
environment with low downdraft CAPE (under 500 J/kg) amidst
similarly low mixed layer CAPE, such that risk of strong winds
or hail is minimal. The marginal instability will likely trend
lower as drier air near the surface advects in simultaneous with
the ongoing convection, so would not expect an uptick in
thunderstorm chances towards the evening.

KEY MESSAGE 2: Tranquil weather will prevail tonight through at
least Monday morning areawide, associated with a wedge of deep
layer ridging in place north of the cold front as it settles
well to our south. The next chance of rain begins Monday with a
fairly uncertain forecast of rainfall chances throughout the
period from Monday through Wednesday, tied to the northward
progress of an anticipated slow moving wave of low pressure
along a quasi-stationary front. This system will have the
ingredients for very heavy rainfall amounts, and an excessive
rainfall outlook currently is in place to our south where the
consensus footprint is located.

Rainfall amounts and chances for any measurable rain taper off
sharply moving northward from southern Vermont and southern
Adirondacks. The northward extent currently peaks early
Tuesday, although the wetter/farther north scenarios lead to a
later timing of the rainfall. The wettest guidance shows
significant rainfall is possible across our region, and have
noted some of the latest deterministic guidance shows the
footprint of heavy rain extending into southern Vermont. We`ll
watch these trends closely given the potential impacts. At this
time we have tilted sky cover a bit towards mostly cloudy skies
progressing northward on Tuesday, and if trends in the data
suggest a more northward footprint of deep moisture and rain we
will see cloudy skies along with temperatures trending cooler in
the coming days. High temperatures will be heavily dependent on
the position of the front; if it tends to be farther south,
we`ll see less moisture/precipitation leading to highs in the
80s, while more northward location will support wetter
conditions leading to temperatures mainly in the 70s but with
higher humidity.

KEY MESSAGE 3: A cold front will eventually pass through late next
week, likely late Thursday or Friday. Out ahead of it, the heat and
humidity will gradually build. By Thursday, temperatures will likely
reach the mid 80s to lower 90s. Dew point will gradually rise well
into the 60s. However, the airmass will be less warm than last week
and its residence time will be shorter, so there will be less time
for the heat to build in from the southwest. Showers and storms
should accompany the cold front, and the potential for strong to
severe storms will be watched as its exact strength and timing
become more certain. Behind the front, a drier and somewhat cooler
airmass looks to persist into mid-July.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...The last few showers are shifting south of
KRUT at this time. Skies will trend mostly clear overnight with
winds quickly becoming calm or terrain driven. On one hand, dry
air is shifting into the region with a front now to our south,
but it will also be cooler with a better opportunity to radiate
than the last several days. For now, depicted fog in TEMPOs for
fog favored terminals and decided to include KRUT since it
rained there within the last hour, mostly 06z-10z. Winds
favored some prevailing fog at KMPV, but remained optimistic
with 3SM through 12z, but it could easily dip towards IFR.
Otherwise, after 12z, mainly fair weather cumulus at or above
7000 ft is expected with northwest winds around 5-9 knots.


Outlook...

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

&&

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

&&

$$

WHAT HAS CHANGED...Kutikoff
DISCUSSION...Myskowski/Kutikoff
AVIATION...Haynes