-- Discussion containing changed information from previous version are highlighted. --
732
FXUS61 KBTV 191128
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
728 AM EDT Wed Jun 19 2024

.SYNOPSIS...
Dangerous heat and humidity across the region today into
Thursday. Highs in the 90s will combine with humid conditions to
create heat index values up to 105. Please be sure to take
appropriate precautions to avoid heat stress through the
remainder of this week. Isolated to scattered thunderstorms are
possible again today, but greater chances for showers and
thunderstorms, a few possibly severe, arrive Thursday.

&&

.NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
As of 718 AM EDT Wednesday...Morning temperatures around the
Burlington Airport only dropped to right around 80 degrees
(warmer than our average daily maximum temperature), which
could be a daily record warmest minimum temperature if BTV
doesn`t drop further this evening. As such, we are starting
quite warm with some mid clouds. Once the clouds break, heating
will rapidly increase with dangerously hot conditions returning.
Showers and thunderstorms are already forming this morning being
kicked off by a mid level disturbance left over from yesterday`s
thunderstorms. With the heat, instability, and a triggering
mechanism, we could see isolated severe thunderstorms; have a
plan for thunderstorms today.

Previous Discussion...Elevated instability is evident across
portions of southern Canada and could kick off an isolated
shower or thunderstorm this morning across the North Country.
Best chances will be 9am-2pm across central Vermont and the
Adirondacks. Thunderstorm chances will be 10-20% in this time
frame with ridging aloft potentially being the foil for
sustained convective activity. Should something get going,
damaging winds will be possible as well as localized heavy
rainfall.

Heat remains the main focus through Thursday with dangerously
hot conditions continuing. Some locations could possibly not dip
below 77 this morning resulting in an incredibly warm start. A
rapid heat-up is expected again with potential for slightly
higher humidity. Dew points in the mid 70s are expected and
could briefly push portions of Addison/Rutland/Chittenden
County to a 105 heat index; today will be the hottest day.
Clouds and showers could be the foil if convection gets going
however. Another warm night is ahead with continued heat for
Thursday.

For Thursday, conditions will warm early, but shear aloft from
an approaching front will likely begin some marginal cooling for
northern locations towards the Canadian border. The front poses
another concern with shower chances increasing north to south.
With additional forcing, increasing wind shear, and oppressive
heat, marginal to slight (5-15%) chances of severe thunderstorms
are expected. Unlike yesterday and today, this will be a
stronger trigger for convection supported by height falls and
cooling aloft. Damaging winds will be the primary threat from
any storms.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
As of 308 AM EDT Wednesday...The cold front will still be over
southern Vermont on Friday and it looks to take long enough to drop
to the south that some instability will be able to develop. With
forcing from the front and more shear, some isolated severe storms
are still possible. However, they look less widespread than
Thursday. There is still some model disagreement on the timing of
the frontal passage so if it passes earlier in the day, that will
keep the severe threat to the south. There should be a break in the
precipitation Friday night as high pressure is briefly able to build
into the region from Canada. It should also be able drop dew points
into the 50s in northern areas though they will be stuck in the 60s
in southern areas. Lows Friday night will be in the 50s and low 60s.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 308 AM EDT Wednesday...The front looks to push back north
into the region on Saturday, and it will bring some showers and
possible thunderstorms. However enough colder air will be able
to drain down from the north at the surface that it will keep
the lower atmosphere stable and any instability will be
elevated. This will prevent a severe threat. The front looks to
stall over the region and showers are possible into Sunday. A
low pressure system moves through Sunday into Sunday night and
it will cause more widespread rainfall. PWATs will increase back
close to 2 inches for Sunday so areas of moderate to heavy
rainfall will be possible. After the low moves out, a warming
trend will occur, though temperatures will not approach the
levels of this week. Dew points look to stay in the 60s for much
of the period so while it will not be as humid as this week, it
won`t feel very refreshing either.

&&

.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
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Through 12Z Thursday...A few areas of fog formed last night and
are mostly dissipating; SLK is maintaining some MVFR VIS, but
that should be over by 12Z. A mid level vorticity lobe is
evident with showers and thunderstorms forming this morning in
St Lawrence County just east of MSS and southwest of SLK in
Herkimer County. This area will expand and move east through the
day with some isolated thunderstorms possible for most
terminals. Best chances will be at SLK 12-16Z and 14-20Z
elsewhere as the mid level energy moves through the North
Country. Otherwise, hot and hazy conditions likely with
potential for some slant-wise visibility reductions.


Outlook...

Thursday: VFR. Likely SHRA, Chance TSRA.
Thursday Night: VFR. Chance SHRA, Chance TSRA.
Friday: VFR. Slight chance SHRA.
Friday Night: VFR. Slight chance SHRA.
Saturday: Mainly VFR, with local MVFR possible. Chance SHRA,
Slight chance TSRA.
Saturday Night: Mainly MVFR, with areas IFR possible. Likely
SHRA, Slight chance TSRA.
Sunday: Mainly IFR, with areas MVFR possible. Likely SHRA, Slight
chance TSRA.
-- End Changed Discussion --

&&

.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 19:
KBTV: 100/1995 Forecast 94
KMPV: 95/1995 Forecast 91
KPBG: 93/2001 Forecast 90
KMSS: 94/1955 Forecast 91
KSLK: 93/1994 Forecast 88

June 20:
KBTV: 95/2012 Forecast 92
KMPV: 90/2020 Forecast 90
KPBG: 94/1964 Forecast 87
KMSS: 92/2012 Forecast 85
KSLK: 92/1995 Forecast 83


Record High Minimum Temperatures:

June 19:
KBTV: 78/1923 Forecast 77
KPBG: 70/1949 Forecast 74

June 20:
KPBG: 70/1953 Forecast 71
KSLK: 68/2012 Forecast 65

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Heat Advisory until 8 PM EDT Thursday for VTZ001>011-016>021.
NY...Heat Advisory until 8 PM EDT Thursday for NYZ026>031-034-035-
     087.

&&

$$
SYNOPSIS...Boyd
NEAR TERM...Boyd
SHORT TERM...Myskowski
LONG TERM...Myskowski
AVIATION...Boyd
CLIMATE...Team BTV