069
FXUS61 KBTV 130632
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
232 AM EDT Mon Jul 13 2026
.WHAT HAS CHANGED...
As of 229 AM EDT Monday...
A Heat Advisory has been issued across much of Vermont and northern
New York for Tuesday afternoon. The Storm Prediction Center has
expanded the forecast region of severe weather in our region,
and upgraded areas along the International Border to an Enhanced
Risk (Level 3 of 5).
&&
.KEY MESSAGES...
As of 229 AM EDT Monday...
1. Heat will begin to build, with a Heat Advisory posted for
most all of Vermont and northern New York on Tuesday. Some localized
fire weather concerns are possible.
2. A sharp cold front is expected to produce strong to severe
showers and thunderstorms Tuesday evening and overnight. A few
storms may be capable of significant severe weather hazards.
3. Seasonable temperatures are generally expected for the
latter half of the week into the weekend, with a few chances for
showers possible.
&&
.DISCUSSION...
As of 229 AM EDT Monday...
KEY MESSAGE 1: Today will be another nice day. Heat is expected to
build, but dewpoints will remain low today. A shortwave will
progress southeast today, but with significant low level dry air, it
may struggle. Still, high res guidance has increased the area of
radar returns, and so the forecast continues to indicate a slight
chance of some afternoon showers today. Southwest winds will help
usher in the warmer weather, and it will bring some breezier weather
compared to the last couple days with some winds to 15 mph, mainly
across northern New York. Within and showers that may develop, there
may be some embedded gusts given the evaporative cooling amidst the
dry low-level environment.
Tuesday will be the peak of a brief, but potent, surge of heat.
Observations upstream indicate that the NBM forecast for dewpoints
may be underforecasting our region, and slightly elevated dewpoints
upwards. The latest forecast runs have also nudged their 925mb
temperatures up just a bit more, and so much of the forecast area is
poised to hit 90s with surface dewpoints in the mid 60s, locally
near 70, especially across the St. Lawrence Valley. With this,
forecast heat indices have crept up towards 93-103 for the region.
Southwesterly winds will increase further as well, with speeds 10-20
mph across the entire region, and gusts 20-35 mph. Sustaining well-
mixed conditions will likely be what keeps us below 100, but there
is a real possibility a few places might reach triple digits. The
heat will be brought to a close by a potentially significant frontal
boundary Tuesday evening into Tuesday night. Even with higher
dewpoints, the warmer temperatures will push south-central Vermont
minimum relative humidity values towards 35 percent. Parts of these
areas have escaped recent rainfall, and the combination of sun,
winds, and heat could drive localized fire weather concerns.
KEY MESSAGE 2: The range of forecast guidance available has been
consistent in depicting a cluster of powerful thunderstorms from
about 6PM - 4AM descending north out of Canada and gradually
dissipating after passing over the international border. Some of
these storms may be capable of significant severe weather.
Much of Tuesday afternoon will be stable, as a warm layer in the mid-
levels will effectively cap convection. By evening, height falls
will begin to erode that region of mid-level warmth. Given
temperatures will still range in the upper 80s to mid 90s, the
region will begin to quickly destabilize while a powerful cold front
drops south of Montreal about 8 PM Tuesday. CAPE values are high,
ranging between 2000-3000 J/kg, and enhanced west-northwest flow
channeled between an anomalous high in the central US and an
anomalous upper low developing across eastern Quebec will result in
0-6km shear approaching 55-60 kts. Shear is mostly unidirectional
across the region, but the development of any mesoscale low, may
allow flow to back southwesterly as the boundary shifts south. This
potential is indicated in the extended 00z HRRR run, and even shows
up within the 00z GFS. Thus, thunderstorms are expected to initially
be discrete, but quickly organize into broken line segments. Any
bowing that takes place may allow for some rotation to develop as
well. Remnants of an elevated mixed layer will be present, but it
will be shifting south somewhat before thunderstorms initiate. So
the timing of strongest thunderstorms will be in that 6pm-midnight
window and along the international border. After becoming briefly
intense, they will then gradually weaken as they advance southwards
across the rest of our forecast area.
All storm threats may occur with this, but for now the forecast
grids indicate heavy rain and gusty winds. Some hail could be
favored while the storm mode is more discrete, and a tornado cannot
be entirely discounted within the development of any bowing
segments. The Storm Prediction Center has forecast an Enhanced Risk
(Level 3 of 5) of Severe Storms along the international border. This
indicates the potential for widespread strong to severe
thunderstorms with significant intensity.
Not to be left out is the heavy rainfall potential. If clusters are
limited, then we`ll have heavy rainfall within strong to severe
storms, but may miss out on any flood potential due to their fast
motions. However, if a broader area of thunderstorms develop, some
forecast evolution depicts thunderstorms redeveloping on the western
periphery of bowing segments in the Northeast Kingdom and resulting
in a swath of high rainfall totals as they move southeast across
northern Vermont, especially. The present forecast shows a sharp
gradient with the higher rainfall totals favored across far northern
Vermont, with values of 1-1.5" indicated from eastern Franklin
Vermont to Essex County, Vermont.
After Wednesday morning, the front should be positioned near or
south of the area. Activity will dwindle, and somewhat cooler air
will begin the process of moving in. Still on the warm side with 80s
for most, and perhaps some readings in the lower 90s for Rutland and
Windsor Counties.
KEY MESSAGE 3: Into the latter portion of this week and the weekend,
temperatures will remain relatively seasonable to seasonably warm
increasing from the low 70s to near 80 on Friday to the upper 70s to
mid 80s by the start of next week. While moisture slowly returns by
the start of next week, dewpoints in the upper 40s to mid 50s will
make things feel comfortable. Synoptically we will remain under
cyclonic northwesterly flow as a cyclonic gyre looks to become
stagnant over northern Quebec, keeping ridging across the west, and
a favoring the potential for a few shortwaves to pass through the
area into the weekend. Timing and spatial patterns of any of these
shortwaves remains muddied as these will likely be associated with
convection and mesoscale processes. That being said, there is a
growing signal that better chances for any precipitation will be
Saturday into Sunday with a diving shortwave across the Great Lakes.
Questions remain where the shortwave sets up in the base of the
trough. GEFS and Euro ensembles are fairly consistent with
increasing precipitation during the day Saturday into Saturday night
as a trough swings through the region with lingering showers into
Sunday. The Canadian model solutions favor a more southerly stream
of energy that would keep most of the region dry through the
weekend. Trends have favored southern Vermont as a target for better
precipitation chances taking the average of the aforementioned model
solutions.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday...Prevailing VFR conditions are expected at all
terminals through the TAF period. Dry air at the surface and aloft
should keep fog at bay, however, SLK has already reached its
crossover temperature due to good radiational cooling. Confidence in
fog tonight is relatively low, in part also due to increasing cloud
cover from the northwest from convection across western Quebec.
However, given they are already at crossover, have added a TEMPO for
MVFR vsbys at SLK from 09-11Z. MPV may possibly also see some VCFG,
though confidence is higher at SLK for any fog. Winds today will
start off light from the south (around 5-10 knots), and trend more
southwesterly by early this afternoon. Channeled southwest flow at
MSS/SLK could bring intermittent gusts to 15-20 kts through this
afternoon. Clouds may briefly increase this afternoon with a
sprinkle or two at BTV/MPV, but PoPs remain below 30% with low
confidence. Winds will trend towards calm with a scattered deck of
stratus around 10,000ft agl overnight tonight.
Outlook...
Tuesday: VFR. Windy with gusts to 30 kt. NO SIG WX.
Tuesday Night: VFR. Chance SHRA, Slight chance TSRA.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. Slight chance SHRA, Slight chance TSRA.
Thursday Night: VFR. Slight chance SHRA.
Friday: VFR. NO SIG WX.
&&
.CLIMATE...
High temperatures on Tuesday will be hot, but we are at the
climatological warmest part of the year. Therefore, it is far
from a certainty that any records will occur. At this time, PBG,
MPV, and MSS are the more likely long-term climate sites to
set a record. See below for current records:
Max Temp Records
Date BTV MPV MSS PBG SLK
07-14 100|1995 94|1952 92|2012 95|1952 95|1934
High Min Temp Records
DatePBG
07-14 70|1974
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Heat Advisory from 11 AM to 8 PM EDT Tuesday for VTZ001>011-
016>018-020-021.
NY...Heat Advisory from 11 AM to 8 PM EDT Tuesday for NYZ026>029-
031-035-087.
&&
$$
WHAT HAS CHANGED...Haynes
DISCUSSION...Danzig/Haynes
AVIATION...Danzig
CLIMATE...NWS BTV
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