040
FXUS61 KBTV 231105
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
705 AM EDT Thu May 23 2024

.SYNOPSIS...
Scattered showers thunderstorms are moving through the North
Country this morning. A surface boundary will push these
showers and thunderstorms eastward into New Hampshire by this
afternoon. After a period of drier conditions, chances of
showers, thunderstorms, and a cooling trend return late this
weekend into early next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 658 AM EDT Thursday...Main adjustment was to increase
shower coverage over St Lawrence County in northern New York
with light rain showers continue. Thunderstorms have largely
settled down in to isolated to scattered showers for the time
being. However, given breaks in cloud cover, surface instability
will increase as the sun climbs resulting in the return of
isolated to scattered thunderstorms for the morning. Otherwise,
the forecast is right on track with another unseasonably warm
day, but fortunately not as hot as yesterday.

Previous Discussion...Scattered showers and thunderstorms are
moving through the North Country this morning along and ahead of
a front. While surface instability is nil due to nocturnal
stabilization, elevated instability and strong ascent along
prefrontal troughs are kicking off and maintaining thunderstorms
overnight. Most cells have been weaker variety, but a couple
have had elevated cores with 50+dbzs reaching 25-28kft. These
cells are capable of gusts in excess of 40 mph, frequent
lightning, and some hail generally to around 0.5". Rainfall
amounts with stronger cells have been less than 0.5", but rates
are higher with 0.36" falling in 15-25 minutes. This could lead
to ponding in poorer drainage areas and urban streets.
Convection will push through Vermont by early afternoon.

Otherwise, another warm afternoon is expected with clearing
skies and a lack of strong cold air advection. Highs will be in
the upper 70s to low 80s in general. Dry conditions will prevail
tonight as another front approaches from the north for Friday.
This boundary is expected to be mostly dry, but cannot
completely rule out a stray shower across northern Vermont. More
notable, is the tighter thermal packing supporting some cold air
advection and breezes for Friday. Temperatures will be
decreasing with highs generally in the 70s; a few spots in
southern Vermont could still hit 80; dew points will be falling
as well tamping down the mugginess.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
As of 314 AM EDT Thursday...With drier conditions and much lower
dew points, Friday night will likely be the coolest evening
we`ve had in about a week. Overnight lows will be in the 59s
with around 50 degrees for broader valleys. By Saturday, the
next trough will be approaching, but the parent low will likely
become highly barotropic and potentially begin retrograding back
towards central Canada according to mid-range models. This would
support increasing shower chances Friday afternoon, but with
decreasing forcing. Have opted to keep thunderstorms out of the
forecast for north given projections of weakening upper level
support mechanisms. Expect another unseasonably mild day with
highs in the mid/upper 79s to around 80 degrees.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 314 AM EDT Thursday...Low pressure crossing just north of the
international border Saturday night will drag a cold front through
the forecast area, kicking off an active period with some showers
and thunderstorms lingering into Sunday. Another low pressure system
will steer across the Great Lakes into Canada, bringing more chances
of precipitation for the first half of the new work week. This
system still appears to be a slow moving storm, providing rounds of
precipitation into the end of the week. All of this showery and
cloudy weather will cause a downward trend for high temperatures,
starting Sunday about 5-10 degrees above average in the upper 70s to
lower 80s, then becoming closer to seasonal normals by the second
half of the week in the mid 60s to lower 70s. Low temperatures are
forecast to remain around the lower 50s to lower 60s, however, there
is the chance for lows to fall later in the week, indicating the
potential for isolated frost.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Through 06Z Friday...There will be showers and some embedded
thunderstorms throughout the night tonight, but there remains
an element of variability in coverage and location of these
showers/storms. Highest confidence in showers is across the
Champlain and St. Lawrence Valleys, and thunderstorms are most
likely at MSS and RUT, though not out of the question at any
site, including BTV. Chances for precipitation will generally
taper off beyond 12-15Z Thursday. In any thunderstorm,
visibility and ceiling could lower, but the exact values and
timing of this is difficult to ascertain at the moment. We will
be sending amendments as the picture becomes clearer over the
next few hours. SLK is the site most likely to have ceilings
drop to at least MVFR levels around 11-14Z Thursday. Following
the precip Thursday morning, sites will experience a lessening
of cloud cover throughout the day. Due to efficient atmospheric
mixing, wind gusts out of the west-southwest could gust 15-20
knots from 14Z Thursday to around 00Z Friday.

Outlook...

Friday: VFR. NO SIG WX.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Slight chance SHRA.
Saturday Night: VFR. Chance SHRA, Slight chance TSRA.
Sunday: VFR. Slight chance SHRA.
Sunday Night: VFR. Slight chance SHRA.
Memorial Day: Mainly MVFR, with areas VFR possible. Chance SHRA,
Slight chance TSRA.

&&

.CLIMATE...
Record High Minimum Temperatures:

May 23:
KPBG: 65/1964

&&

.EQUIPMENT...
Some ASOS and AWOS equipment have been having communications
issues overnight resulting in missing observations from
BTV/PBG/MVL/MPV and some others. Technicians are being
dispatched to check equipment and address this issue.

&&

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

&&

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