234
FXUS61 KBTV 221714
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
114 PM EDT Sat Jun 22 2024

.SYNOPSIS...
An unsettled pattern will persist into the beginning of next week,
with multiple rounds of showers and thunderstorms. There is the
potential for strong to severe storms Sunday as a cold front moves
through. These storms will also contain heavy rainfall and frequent
lightning.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 113 PM EDT Saturday...Forecast remains in good shape so
only made minor changes to bring it up to date with current obs.
As expected, thunderstorm coverage remains south of our CWA
with showers and patchy fog around as we remain in the cool
sector. Tomorrow will be a totally different story with severe
weather on the table. More on that with the next update later
this afternoon.

Previous discussion...A weak boundary is currently situated
across the North Country and it has caused a few showers to
develop. These showers have been able to saturate the low
levels, and without any flow, patchy fog has developed. It is
going to take awhile for the fog and low stratus to lift today
because a warm front will push into the region and cause a bit
of a surface inversion. Combined with thick cloud cover and
showers, the sun will have a hard time creating any mixing at
the surface.

Elevated convection is beginning to develop tonight due to a
weak shortwave passing into the region. These showers will
continue into the day today as a warm front makes its way north
across the region. Isolated flash flooding is possible if
multiple storms hit the same area, but the threat is low. A few
of these storms could contain lightning but there is not a
severe threat. The front passes north of the international
border Saturday night and there should be somewhat of a lull in
the action, particularly over southern Vermont. The front looks
to stall just north of the international border Saturday night
into Sunday, and it will produce a narrow area of very heavy
rainfall. Now that confidence has increased that it will stall
north of border, the flooding threat in the region has
diminished. However, with the front to the north on Sunday, the
region will get into the warm sector of the storm. This has
caused the severe threat on Sunday to increase. Abundant deep
layer shear will be in place and there should be enough sunshine
for instability to develop. CAPE looks to reach between
1000-1500 J/KG though there is a possibility that it exceeds
those values. It will rely on any convective debris to move out
Sunday morning, so lingering clouds could dampen the risk a
little. There will also be very strong low- level helicity, and
an isolated tornado cannot be ruled out. However, the main
threats will be strong winds and hail. There is also a flash
flooding risk with these storms, given high PWATs and very deep
warm cloud layers. However, fast storm motion will help keep the
risk localized to areas that receive multiple storms.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
As of 420 AM EDT Saturday...Thunderstorms will diminish Sunday night
as the cold front crosses the region and instability wanes. However,
showers will likely persist through much of the overnight,
especially over the higher terrain as flow turns to the northwest.
The upper trough will swing overhead on Monday, so expect ample
cloud cover and scattered to numerous showers through much of the
day. A few rumbles of thunder will be possible, as well. Highs will
be in the mid 60s to mid 70s, but with cloudy skies and breezy
northwest winds, it may feel a little on the cool side. Showers will
wind down Monday night and skies will clear from west to east as the
upper trough departs. Lows will be in the 50s to around 60F.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 420 AM EDT Saturday...Tuesday will be dry as ridging briefly
builds over the area. The break will be short-lived though as a cold
frontal passage will bring another round of showers and
thunderstorms to the region on Wednesday. Some storms could be on
the strong side given CAPE values of 750 to 1200+ J/kg and 0-6km
shear of 30-40kt, but there`s some evidence on model soundings that
there could be a capping inversion around for a good part of the
day. Still, trends will need to be watched as we draw closer to the
middle of next week. Much drier air will work in behind the cold
front, so expect a more prolonged dry spell for the end of next
week. Highs will be back up into the mid and upper 80s ahead of the
front, but then should cool back down into the 70s to around 80F for
Thursday and Friday.

&&

.AVIATION /17Z SATURDAY THROUGH THURSDAY/...
Through 18Z Sunday...A warm front will slowly pass through the
region today and into tonight, bringing showers and low
ceilings. A few of the showers will likely be heavy enough to
briefly lower visibilities to MVFR. Plenty of low-level
moisture remains trapped in place, so the clouds will be much
more stubborn than typical during the day. All terminals are
forecast to be out of IFR by around noon but it looks unlikely
that any of the terminals will improve to VFR conditions that
are not already there. Ceilings should fall back tonight and low
MVFR and IFR conditions look to develop at many of the
terminals again. Patchy fog will probably develop again as well.
It will take until tomorrow morning for the front to push to
the north and have southerly flow clear out the low clouds and
fog. However, a low-level jet will pass overhead and cause LLWS
to develop at all the terminals. Winds at the surface will
generally be light during the period though they will begin to
increase tomorrow morning. Then towards the end of the TAF
period, especially after 15z Sunday, there is increasing potential
for widespread thunderstorms, some of which could be severe
producing damaging wind gusts.

Outlook...

Sunday: Mainly VFR, with local IFR possible. Definite SHRA,
Chance TSRA.
Sunday Night: Mainly MVFR, with local IFR possible. Chance SHRA,
Chance TSRA.
Monday: MVFR/IFR conditions possible. Chance SHRA.
Monday Night: VFR. Chance SHRA.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. Chance SHRA.
Wednesday: Mainly VFR, with local MVFR possible. Chance SHRA,
Chance TSRA.

&&

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

&&

$$
SYNOPSIS...Myskowski
NEAR TERM...Chai/Myskowski
SHORT TERM...Hastings
LONG TERM...Hastings
AVIATION...Chai