-- Discussion containing changed information from previous version are highlighted. --
726
FXUS61 KBTV 172304
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
704 PM EDT Mon Jun 17 2024

.SYNOPSIS...
A period of dangerously high heat starts on Tuesday and will persist
into Thursday. Highs will reach well into the 90s each day, and
overnight temperatures will remain muggy and uncomfortable. Please
be sure to take appropriate precautions to avoid heat stress through
the remainder of this week. Although an isolated thunderstorm can`t
be ruled out Tuesday or Wednesday, our next best chance for rain
arrives late Thursday into Friday with a cold frontal passage.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
-- Changed Discussion --
As of 700 PM EDT Monday...Southerly flow around 1025mb high pres
off the New England Coast continues to advect higher humidity
values and warmer temps into our fa. The combination of
southerly winds and dwpts into the 60s, wl result in lows only
lower 60s SLK/NEK to near 70F in the urban heat islands of the
CPV. Strong subsidence and associated deep dry layer should
prevent any convection from developing this evening. Have made
some minor tweaks to temps/dwpts and winds, otherwise fcst is
on track.

Previous discussion below:
The forecast remains on track, with a period of dangerously
warm temperatures expected to start Tuesday.

Ample sunshine across much of the region has allowed temperatures to
warm into the upper 70s to mid 80s in most locations this afternoon.
Dewpoints are already creeping up as well; readings in the mid and
upper 60s are fairly common. Moisture will continue to increase
tonight, and the result will be a muggy overnight, especially in the
St Lawrence and Champlain Valleys, where lows will only drop to
around 70F. Low to mid 60s are expected elsewhere.

Things really start to heat up on Tuesday, with 925mb temperatures
approaching 25-27C. The question is how much cloud cover there will
be through the day. A weak shortwave currently moving into western
NY is producing some convection this afternoon. This feature will
continue to slowly push eastward tonight and Tuesday. While current
expectations are that the convective activity will wane as it
approaches the North Country, there very well could be debris clouds
passing overhead during the morning and early afternoon hours. While
it`s hard to discern just how extensive this cloud cover may be,
there are some indications that it could be thick enough to limit
warming just a touch tomorrow. Have therefore lowered the maximum
temperature forecast just a tad, though really just by a degree or
two - not enough to make an appreciable difference. With dewpoints
to approach or even exceed 70F, still anticipate dangerously high
heat index values in the mid/upper 90s to around 100F. Even if we do
get more clouds than expected, it will still be very warm tomorrow,
so please make sure to follow the proper heat precautions.

Otherwise, while a stray thunderstorm or two can`t be totally ruled
out given the abundance of moisture and instability that will be
available, continue to believe that tomorrow will be dry. Tuesday
night will be even warmer and more uncomfortable than tonight; lows
will likely remain in the 70s in the wider valleys, with upper 60s
in higher elevations.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
As of 333 PM EDT Monday...A prolonged period of dangerous heat is
expected to continue across the region through Thursday. A strong
upper level ridge will continue to amplify as it shifts towards the
region, with 925mb temperatures reaching or exceeding +25C. The
current forecast shows high temperatures soaring into the 90s for
Wednesday and Thursday, with dewpoints in the upper 60s to low 70s
leading to heat indices in the mid 90s to low 100s. There is a non-
zero chance for precipitation throughout the period given the
abundant moisture and hot temperatures. In addition to the hot
daytime temperatures, overnight low temperatures will also remain
warm with mist places struggling to drop below 70s which will add to
the cumulative impacts of the heat. Experimental NWS HeatRisk
highlights the threat well, showing major to extreme risk of heat
related impacts for the middle of this week. Be sure to practice
heat safety by staying hydrated, avoiding strenuous outdoor activity
and checking up on your family, friends, neighbors, and those most
vulnerable to heat.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 333 PM EDT Monday...The ridge begins to flatten out and a
frontal boundary will start to drop through the region Thursday
night into Friday, providing some relief to the heat. While the
overall forcing and moisture is rather lackluster, instability will
be quite high given the heat and humidity which will may allow for
showers and thunderstorms to develop along the front. Temperatures
during the day on Friday will be cooler but still be on the warm
side for this time of year, with high temperatures in the 80s to
lower 60s across southern Vermont depending on how quickly the front
passes through. Temperatures heading into the weekend will remain on
the warmer side of normal heading into the weekend, with more
chances for showers as we head into the weekend.

&&

.AVIATION /23Z MONDAY THROUGH SATURDAY/...
Through 18Z Tuesday...VFR conditions will prevail through the
TAF period. Skies trending toward FEW-SCT AOA 6000 ft at all
terminals by 22z Mon, with mainly mid/high clouds expected.
Some localized MVFR/IFR will be possible in patchy fog 08z-12z,
mainly in CT River Valley and St Lawrence Valley. Slight chance
of showers/thunderstorms after 12z Tue, especially over higher
terrain. South/southwest winds 5 to 10 kt with occasional gusts
to 20 kt will become light and variable after 00z Tue, then
picking back up to around 5 kt late in the period.

Outlook...

Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. Slight chance SHRA, Slight chance TSRA.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. Chance SHRA, Slight chance TSRA.
Thursday Night: VFR. Chance SHRA, Slight chance TSRA.
Friday: VFR. Chance SHRA, Slight chance TSRA.
Friday Night: Mainly VFR, with local IFR possible. Slight chance
SHRA.
Saturday: Mainly VFR, with local MVFR possible. Chance SHRA,
Slight chance TSRA.

&&

.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:
KBTV: 97/1994 Forecast 96
KMPV: 93/1994 Forecast 92
KPBG: 94/1994 Forecast 92
KMSS: 97/1994 Forecast 94
KSLK: 94/1907 Forecast 91

June 19:
KBTV: 100/1995 Forecast 97
KMPV: 95/1995 Forecast 93
KPBG: 93/2001 Forecast 94
KMSS: 94/1955 Forecast 93
KSLK: 93/1994 Forecast 91

June 20:
KBTV: 95/2012 Forecast 96
KMPV: 90/2020 Forecast 92
KPBG: 94/1964 Forecast 92
KMSS: 92/2012 Forecast 91
KSLK: 92/1995 Forecast 90


Record High Minimum Temperatures:

June 19:
KPBG: 70/1949 Forecast 69

June 20:
KPBG: 70/1953 Forecast 72
KSLK: 68/2012 Forecast 66

&&

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

&&

$$
SYNOPSIS...Hastings
NEAR TERM...Hastings/Taber
SHORT TERM...Kremer
LONG TERM...Kremer
AVIATION...Hastings
CLIMATE...Team BTV