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120
FXUS61 KBTV 141635
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1235 PM EDT Fri Jun 14 2024

.SYNOPSIS...
A cold front will help produce isolated showers and possibly
a few thunderstorms late this morning into the afternoon. Dry
weather with abundant sunshine expected this weekend. Then by
Monday, warm and moist air will shift back into the region.
Temperatures warming into the upper 80s to mid 90s is expected
by the middle of next week. In conjunction with high dewpoints
and warm overnight conditions, heat impacts are likely next
week.

&&

.NEAR TERM /THROUGH SATURDAY/...
-- Changed Discussion --
As of 1230 PM EDT Friday...A few showers have begun to develop
across southern and eastern vermont but they have been
unimpressive so far. There should continue to be isolated to
scattered showers this afternoon in those areas with the
possibility that one of two of them could be severe. Sunshine is
helping the atmosphere destabilize a bit but drier air in the
mid levels is quickly moving down from the north.

Previous Discussion...The prefrontal trough that downed several
trees and powerlines along the Route 11 corridor is exiting
east. Nevertheless, there are still showers developing, and one
thunderstorm north of Burlington. Forecast models are not
handling this very well, and have tried to broadly depict this
activity also sliding east, but this could impact our chance for
thunderstorms in the afternoon as well as our high temperature
forecast. For now, forecast temperatures in Vermont are likely
to warm to the mid 70s to lower 80s with surface dewpoints still
in the upper 50s to lower 60s. So if any afternoon convection
is intense enough, it could entrain some dry air and relatively
fast flow aloft to produce strong to locally severe downburst
winds. The highest CAPE and shear lies across southern Vermont,
and that`s where a marginal risk outlook (Level 1 of 5) remains
for the idea of localized, short- lived severe potential. Little
to no organization is expected due to the mid- level dry air.

The front slides south about 6 or 7 PM, but a few localized
showers may linger as the dewpoint boundary doesn`t move south
until overnight. Cool north flow should bring us into the mid
40s to mid 50s, with the warmest temperatures in the lower
Connecticut River Valley. Exceptionally beautiful weather is
expected on Saturday. There should be a steady north wind, low
dewpoints, and temperatures in the 60s to lower 70s. A nice
start to what should be a great weekend. PoPs nil Saturday.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
As of 335 AM EDT Friday...After a spectacular day on Saturday, winds
should diminish quickly after sunset. With clear skies and light
winds and a 1020mb surface high building into the region, it should
be a good radiational cooling night with widespread lows in the 40s,
except mid to upper 30s for the sheltered colder hollows and low 50s
for the immediate Champlain Valley.

Father`s Day looks to be quite similar to Saturday, with lighter
winds and daytime highs in the 70s. Dew points look to be a tad
higher, but still generally in the 40s. Once again, with abundant
sunshine and comfortable humidity, get outside and enjoy the
gorgeous conditions. And if you haven`t already done so, you might
want to set aside some time to put in the window AC as summer heat
and humidity will be making a return in a big way for much of the
upcoming work week.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
As of 335 AM EDT Friday...Let`s cut to the chase. There will likely
be a prolonged significant heat event for much of the upcoming work
week, with many locations potentially experiencing a three or four
day heat wave. Ensemble guidance shows good agreement that a 594+ Dm
upper ridge will build across the southeast U.S., allowing for
summer heat and humidity to be advected into our region. NAEFS/GEFS
ensemble guidance shows height fields at 99th percentile to maximum
of climatology for our region from Tuesday into Thursday. Indeed,
some deterministic guidance even has 600 Dm ridge centered right
over parts of New England. Daytime highs could approach or exceed 90
degrees each day from Monday into Thursday with little nighttime
relief. Some locations, including Burlington, could see the first
heatwave of the season, defined as three consecutive days of 90+
degree high temperatures. With dew points in the 60s, heat index
values could be in the mid to upper 90 range, especially on Tuesday
and Wednesday. There are some indications that a cold front would be
delayed or hung up across our far northern zones. If that happens,
then Thursday could be another uncomfortably hot and humid day with
heat index values once again in the mid to upper 90s range. Once
again, at this time frame in the forecast cycle, the fly in the
ointment would be the development of thunderstorms.

Given plenty of daytime instability and the potential for somewhere
in the Northeast to be on the periphery of a building heat dome,
there is the potential for strong to severe thunderstorms to develop
and ride up and over a crest of high pressure. Whether or not your
location can muster three straight days of 90+ highs, or is being
issued with Heat Advisories, the new experimental WPC heat risk is
now highlighting the growing potential for moderate to major (level
2 to 3 out of 4) risks of heat-related impacts on Tuesday and
Wednesday next week. It is not out of the question that if
thunderstorms do hold off, heat index values could even push 100
degrees for part of the Champlain Valley and the St Lawrence Valley
from a combination of air temperatures in the low to mid 90s and dew
points in the mid 60s to low 70s. This would result in a low but non-
zero chance of extreme risk (level 4 of 4) of heat related impacts.
The extreme heat risk would be more plausible on Thursday, given the
accumulated effects of prolonged heat if cooling relief does not
arrive by then. Given that the major heat risk category affects
anyone without effective cooling and/or adequate hydration, the
public is encouraged to take preventative measures such as having
access to AC or minimizing vigorous outdoor activities during the
peak of the heat.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Through 12Z Saturday...Mostly isolated showers cover Vermont and
northern New York with one thunderstorm just north of BTV. MVFR
ceilings are being noted at KMSS, and should remain through
about 14-15z before lifting. A cold front will shift southeast
today and has just crossed Ottawa. This front will result in a
transition to northwest winds today with speeds mainly between 6
and 12 knots with a few gusts 16 to 19 knots. Isolated
convection could continue to develop along and ahead of the cold
front, which will pass south of the region by about 20 to 22z.
Beyond 00z, winds will become northerly at 5 knots or less, and
perhaps even terrain driven at KRUT. Skies will gradually clear
out.

Outlook...

Saturday: VFR. NO SIG WX.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. NO SIG WX.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.

&&

.CLIMATE...
Hot temperatures will result in values near records by the
middle of next week. Below are some of the records under threat
of being broken.

Record High Temperatures:

June 18:
KMPV: 93/1994 Forecast 91

June 19:
KPBG: 93/2001 Forecast 92
KMSS: 94/1955 Forecast 93
KSLK: 93/1994 Forecast 91

June 20:
KBTV: 95/2012 Forecast 96
KMPV: 90/2020 Forecast 93
KMSS: 92/2012 Forecast 92


Record Low Temperatures:

June 16:
KSLK: 32/2020 Forecast 35


Record High Minimum Temperatures:

June 19:
KPBG: 70/1949 Forecast 68

June 20:
KPBG: 70/1953 Forecast 69
KSLK: 68/2012 Forecast 64

&&

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

&&

$$
SYNOPSIS...Haynes
NEAR TERM...Haynes/Myskowski
SHORT TERM...Chai
LONG TERM...Chai
AVIATION...Haynes
CLIMATE...Team BTV