874
FXUS61 KBTV 230538
AFDBTV

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

.SYNOPSIS...
Scattered showers and a few 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 return late this weekend into early next week. A marked
cooling trend begins Sunday with temperatures trending back
towards seasonal averages next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 115 AM EDT Thursday...Main update was to adjust where
showers and thunderstorms are expected. Some showers have formed
in the northern Champlain Valley and will track northeastward.
Elevated instability remains greater than 250J/kg and will
result in mainly isolated thunderstorms with this feature
through 6AM. More scattered thunderstorms are evident along the
surface boundary in nearing Ottawa as well as south of the
Adirondacks along portions of the Mohawk Valley. These areas
will bring some thunderstorm chances mainly to northern New
York, but cannot rule out a morning storm in southern Vermont as
the Mohawk Valley line tracks eastward.

Previous Discussion...Initial line of thunderstorms along a
prefrontal trough has weakened considerably over our northern NY
counties. Expect these showers to continue to dissipate as they
head northeastward. Looking further upstream, cold front is
moving through southeastern Ontario with a line of thunderstorms
along the front. Expect another round of showers with some
embedded elevated thunderstorms overnight as this boundary
slowly moves through. Previous discussion follows...

An extremely warm day across the region this afternoon as
temperatures have climb into the 80s, and a few spots climbing
into the 90s. With the daytime heating, some isolated garden-
variety thunderstorms have tried to develop across northern New
York, but they have been very few and far between. Chances of
precipitation continue to increase heading into this evening and
the overnight hours as a pre-frontal trough ahead of an
approaching cold front swings through the region, bringing a
line of showers with embedded thunderstorms to the region. The
latest guidance shows this system, and any associated
thunderstorms that form, to be weaker than previous forecasts as
the arrival time does not coincide with the greatest
instability. Temperatures overnight will be quite mild and
muggy, with lows generally in the 60s and dewpoints nearly the
same.

By Thursday morning, the surface cold front will be moving across
the region, with showers coming to an end Thursday afternoon. Since
the frontal passage will occur during the morning hours, the threat
for stronger thunderstorms will be low across our area, with better
chances to our east (as seen in the SPC Day 2 Convective Outlook),
although some thunder cannot be ruled out across our area.
Temperatures during the day will be cooler in comparison to today`s
warmth, although high temperatures will still climb into the upper
70s to mid 50s. Drier conditions will return behind the cold front,
with overnight low temperatures in the 50s.

&&

.SHORT TERM /FRIDAY NIGHT/...
As of 342 PM EDT Wednesday...A low pressure system passing well north
of the international border will bring a chance for showers to only
our very far northern Vermont zones on Friday as a weak surface cold
front crosses the area. Ridge of surface high pressure will then
build into the region Friday night and drier, cooler conditions for
the north country. Maximum temperatures on Friday will range from
the lower to upper 70s. Minimum temperatures Friday night will range
from the mid 40s to mid 50s.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 342 PM EDT Wednesday...The weather will be more active in the
long term portion of the forecast as a persistent surface and upper
level trough becomes anchored over the eastern portion of the United
States. There will be increasing chances for rain showers Saturday
afternoon as a warm front lifts into the area. A surface cold front
will cross Northern New York and Vermont early Sunday morning. Yet
another low pressure system crossing the Great Lakes area on Monday
will bring additional chances for showers Monday and Monday night.
This low will be slow to move away from the region, so showers will
continue right into Tuesday and Wednesday as the north country
remains under cyclonic flow. Models diverge a bit beyond Wednesday.
Temperatures will trend cooler through the long term portion of the
forecast, partly due to showers and clouds which will linger through
most of the period.

&&

.AVIATION /06Z 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 Temperatures:

May 22:
KBTV: 93/1977
KMPV: 90/1994
KMSS: 89/1977
KSLK: 91/1911

Record High Minimum Temperatures:

May 22:
KBTV: 70/1911
KPBG: 65/1975
KSLK: 63/1921

May 23:
KPBG: 65/1964

&&

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

&&

$$
SYNOPSIS...Boyd/Kremer
NEAR TERM...Boyd/Duell/Kremer
SHORT TERM...Neiles
LONG TERM...Neiles
AVIATION...Storm
CLIMATE...Team BTV