-- Discussion containing changed information from previous version are highlighted. --
740
FXUS61 KBTV 031330
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
930 AM EDT Mon Jun 3 2024

.SYNOPSIS...
Another warm and dry day is anticipated with highs well into the
80s again with comfortable humidity values. An isolated terrain
driven shower is possible on Tuesday, followed by increasing
chances of showers and isolated thunderstorms for Wednesday
into Thursday. Cooler temperatures are expected for mid to late
week with highs generally in the mid 70s to lower 80s, while
lows hold in the mid 50s to mid 60s with some increasing
humidity levels.

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
As of 927 AM EDT Monday...Only adjustment was to the sky
forecast. Dry subsidence is promoting fast clearing. There are
some convective debris clouds to our west, but visible satellite
shows them to be very thin, and notched sky cover towards mostly
sunny until we get some cumulus to develop across the mountain
ranges. Have a great day!

Previous discussion below:
The main challenge today wl be intervals of high clouds and
potential impacts on temps. GOES-16 mid level water vapor
imagery shows well defined dry slot overhead, while some
convective debris cirrus is rounding ridge over the northern
Great Lakes. Given the dry air aloft and soundings indicating
very weak instability today, we wl cont with a dry fcst. Saw BTV
reached 86F yesterday and progged 925mb temps are very similar
again today with values in the 19-21C range, so thinking highs
upper 70s to mid 80s. Have 86F here at BTV and 84F at MPV and
82F at SLK. Tonight center of mid/upper lvl ridge is building
directly overhead, while 1018mb high pres is shifting into
central Maine. Winds wl remain light and trrn driven with some
very shallow/patchy fog possible in the deepest valleys.
However, confidence is low and probability of occurring is
around 5% attm, given recent dry spell, so have not placed in
grids. For Tuesday, have trimmed back pops a little, as forcing
is minimal with mid/upper lvl ridge directly overhead. In
addition, have noted as mixing improves during the late morning
into the aftn hours, sfc dwpts fall back into the upper 40s to
lower 50s, resulting in weak sfc based CAPE values in the
250-400 J/kg range. Have highest pops acrs the mtns of 15-25%,
while keeping the valleys dry attm. Feel given the dry 850-500mb
layer per sounding data, if any showers were to develop areal
coverage would be <10% with very slow storm motions of 10 knots
or less. Progged 925mb temps still range in the 20-21C range,
but feel as convective temps are reached, some cumulus clouds wl
develop over the trrn, which may limit sfc heating a little.
Still another above normal day is anticipated with highs upper
70s to mid 80s, would not be surprised a few upper 80s possible
in the CPV/Urban heat island areas.
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&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 330 AM EDT Monday...Any lingering shower activity that may
develop on Tuesday will dissipate quickly following sunset on
Tuesday with the loss of diurnal heating. Model guidance continues
to be aggressive with developing showers and even a few
thunderstorms on Wednesday. However, one caveat to development these
showers and thunderstorms will be that the upper level ridge is
expected to be centered across the region. BUFKIT soundings show a
plethora of subsidence from 500 mb upwards which is expected to
stunt the development of storms. With the lack of any surface
convergence, we will be relying on the Green and Adirondack
Mountains to be the forcing mechanism to get storms going. Storm
motion is going to be very slow as winds in the layer in which
storms can develop will only be about 5-10 knots. This should keep
much of the activity tied to the higher terrain but a shower or
storm may briefly move into the Valleys of Vermont and New York but
should quickly fizzle apart given the stable regime we are currently
under. Showers and storms are expected to dissipate quickly
following sunset on Wednesday with the loss of heating as well.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 330 AM EDT Monday...Thursday continues to be a head scratcher
as just when you think models are getting a handle on the overall
synoptic situation, the solutions begin to diverge. While it still
looks likely that we will see widespread rainfall on Thursday, the
exact amounts and timing remain very uncertain. This has us capping
our PoPs at 70% but these will likely be increased in the coming
forecast cycles as confidence increases. While the Weather
Prediction Center (WPC) has us in a marginal risk for flash
flooding, neither the rainfall rates or amounts expected should pose
a flood threat at this time.

With the passing of a cold front on Thursday, a major pattern change
is expected to ensue. We`ve been talking about an omega block in the
past several days that has brought us the warm and dry period of
weather we just experienced. However, this block is expected to
shift slightly eastward with New England expected to be stuck
underneath an upper level low late this week and well into next
week. This is expected to bring rounds of showers and a few rumbles
of thunder each day. With anomalously cold temperatures aloft, it
won`t be hard to see convective showers develop each afternoon which
could have the potential to drop some graupel in the stronger
storms. Overall, showers are expected to be quite scattered but it
seems Saturday could be a focus on a more robust round of showers
and thunderstorms. At the 500 mb level, two upper level lows are
expected to phase and deepen across the North Country. This should
allow for a touch of southern stream moisture to wrap into the
region. With increased dynamical forcing coupled with the
thermodynamics of the cold core low, we could see widespread moderate
to maybe even heavy rainfall. Confidence in this exact solution is
low to moderate but it`s safe to say it looks like this weekend will
be on the wetter side.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
Through 12Z Tuesday...VFR conditions will continue at all sites
through this evening with intervals of mid and high level
clouds. Light and variable winds will become north/northwest 3
to 6 knots by 15z, before becoming light trrn driven by 01z this
evening. Given the lack of rain and very dry boundary layer
conditions, potential for fog tonight at SLK/MPV is <5% attm.

Outlook...

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

&&

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

&&

$$
SYNOPSIS...Taber
NEAR TERM...Haynes/Taber
SHORT TERM...Clay
LONG TERM...Clay
AVIATION...Taber