-- Discussion containing changed information from previous version are highlighted. --
430
FXUS61 KBTV 151107
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
707 AM EDT Tue Jul 15 2025

.SYNOPSIS...
High pressure will bring ample sunshine today, though wildfire smoke
will likely keep conditions hazy. Temperatures will climb in
the coming days, with afternoon highs generally in the upper 80s
to lower 90s. Wednesday should be the hottest day, with valley
locations reaching the mid 90s. An approaching frontal system
from the Great Lakes will bring the next chance for showers and
thunderstorms across the region Wednesday night into Thursday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 158 AM EDT Tuesday...The main concerns for the near term will
be reduced air quality from wildfire smoke, followed by building
heat and humidity.

High pressure will continue to settle over the area today, leading
to light north to northwest flow. This has already allowed wildfire
smoke from Canada to spread south across the international border
early this morning, particularly in northern NY and into far
northern VT, where visibilities are 4-8SM and air quality is
reduced. This smoke will continue to spread southward through the
day today, eventually reaching into central/south central VT. The
smoke may thicken up through daybreak under an inversion, but it
should thin out a little as we see daytime mixing. Still, anticipate
hazy conditions through much of the day. Both the state of NY and
state of VT have issued Air Quality Alerts due to fine particulates,
which should remain in effect until midnight tonight.

Otherwise, the concern is the expected warming trend. 925mb
temperatures will approach 25C this afternoon, and other than the
smoke, expect ample sunshine today. Highs will warm into the mid 80s
to around 90F, warmest in the wider valleys. Dewpoints will mainly
be in the lower to mid 60s, which should just keep heat index values
below the 95F threshold for a heat advisory. Still, anyone
outdoors should take heat precautions, especially if they`re in
one of the sensitive groups. There won`t be much relief from the
heat tonight as we`ll stay muggy and mild. Lows will be in the
60s to around 70F.

The heat only increases on Wednesday with 925mb warming to 25-27C,
with afternoon highs in the upper 80s to mid 90s. Many of our
climate sites will be close to daily record highs; see the Climate
section below. Dewpoints will once again rise into the low to mid
60s, though efficient daytime mixing may keep them a few degrees
lower than might otherwise be expected. Still, heat index values
will rise into dangerous levels, especially in the wider valleys
where 95-100F values are likely; it should be 90-95F elsewhere. An
upper shortwave trough and associated frontal system will approach
from the west Wednesday afternoon, but the main effect from this
will be just increasing clouds later in the day. Can`t totally rule
out a thunderstorm or two edging into the St Lawrence Valley or
perhaps popping up over the higher terrain, but warm mid-level
temperatures makes any convection unlikely. If anything does
develop, it would be late in the afternoon and isolated in nature.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
As of 158 AM EDT Tuesday...A prefrontal trough looks to move through
Wednesday night and Thursday morning, bringing a round of showers
and embedded thunderstorms. Conditions will be very favorable for
heavy rainfall, with PWATs around 1.75 inches and very large warm
cloud depths. While storm motion may be on the slower side, it looks
to be just fast enough to prevent much of a flash flood risk, though
the threat still needs to be watched. With the prefrontal trough
looking to come through earlier in the day, the severe threat should
be limited, though a few strong to severe storms still cannot be
ruled out. Thursday has the potential to be the third day of 90
degree temperatures for Burlington and therefore may make the first
heat wave. Confidence is relatively high on both Tuesday and
Wednesday reaching 90 but Thursday is much more in question. The NBM
forecast high is 90 degrees and its probability of 90 or higher is
about 70 percent, but it is still very much conditional. Clouds and
showers look to linger for much of the morning before the prefrontal
trough exits, and how long these stick around will be key. If
clearing happens early enough, it will not take much to reach 90
given the warm airmass but the amount of sun is uncertain at this
time. Dew points will climb significantly for Thursday, reaching the
upper 60s to mid 70s. With a saturated profile, advection and rain
Wednesday night, there is pretty high confidence of these high dew
points. The heat and humidity will cause conditions to approach Heat
Advisory Criteria in the broad valleys, and lows Wednesday night
will be too high to provide much relief.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 158 AM EDT Tuesday...The cold front finally looks to move
through Thursday night and Friday morning. While it will bring the
chance for a few showers and thunderstorms, due to its mostly
nocturnal passage, they look unimpressive. This front will be strong
enough to cause a significant airmass change, with dew points
dropping into the 50s for Friday. Highs should be in the 70s in most
places and lows should be in the 50s in most places Friday night,
and temperatures may even fall into the 40s in the coldest
locations. Dry weather will continue through Saturday before shower
chances return for Sunday. The heat and humidity look to remain
mostly to the south for the start of next week with temperatures
looking seasonable.

&&

.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
Through 12Z Wednesday...Main impacts during this TAF period
will be dense valley fog through 14z Tue, along with widespread
haze through much of the day today. IFR conditions will persist
at KSLK/KEFK/KMPV through 14z, though a gradual improving trend
is expected during that time. Otherwise, expect a mix of
VFR/MVFR with visibility reduced to 5-6SM at times due to
wildfire smoke/haze. Some guidance indicates the potential for
more valley fog late tonight, but certainty is not enough to
include in the TAFs at this time. Skies to remain FEW AOA 5000
ft outside of any fog. Winds light and variable through the
period, mainly terrain- driven.

Outlook...

Wednesday: VFR. Slight chance SHRA, Slight chance TSRA.
Wednesday Night: VFR. Chance SHRA, Chance TSRA.
Thursday: Mainly VFR, with local MVFR possible. Likely SHRA,
Chance TSRA.
Thursday Night: MVFR. Chance SHRA, Slight chance TSRA.
Friday: Mainly VFR, with areas MVFR possible. Slight chance SHRA.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
-- End Changed Discussion --

&&

.CLIMATE...
The current forecast highs for Tuesday and especially Wednesday
will be within a few degrees of daily record highs, which are
listed below.


July 15:
KBTV: 93/2013

July 16:
KBTV: 96/2018
KMPV: 92/1969
KPBG: 95/1969
KMSS: 94/2018
KSLK: 90/1997

&&

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

&&

$$
SYNOPSIS...Hastings
NEAR TERM...Hastings
SHORT TERM...Myskowski
LONG TERM...Myskowski
AVIATION...Hastings
CLIMATE...WFO BTV