000
FXUS61 KBTV 301358
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
Issued by National Weather Service Caribou ME
958 AM EDT Tue Apr 30 2024

.SYNOPSIS...
After isolated to scattered showers with a lower probability of a
thunderstorm this morning, shower chances increase with additional
chances of thunderstorms as a front sweeps through the North
Country this afternoon and early evening. Periods of moderate
rain are expected which could lead to ponding in poor drainage
areas and minor field flooding. Weaker troughs will bring
additional chances of showers later this week, but overall
conditions will be calmer with mild temperatures.

&&

.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
9:55 a.m. update...A few thunderstorms are moving through the
southern portion of the forecast area but these have weakened
this morning as the boundary moves further south. Winds in these
thunderstorms have been gusting up to 30 mph. Some small hail
was reported closer to Albany, but we have had no hail reports
over northern New York or Vermont this morning. Forecast has
been updated to reflect current temps but otherwise remains on
track.

Previous Discussion...Early morning thunderstorm chances have
increased with a ribbon of elevated instability along a relative
warm front moving through the Mohawk Valley into portions of
the Adirondacks and southern Vermont. CAMs may be a little
underdone, but do show weakening of instability towards the
morning hours. Still, can`t completely rule out a rare
thunderstorm especially in the Adirondacks and across southern
Vermont through sunrise. Currently, best chances are in the Star
Lake/Tupper Lake areas and just across the St Lawrence River in
Canada. This will track eastward-northeastward while the main
line of convection will continue in the Mohawk Valley through
Bennington County, Vermont. Portions of Rutland County may see a
stray thunderstorm 6-8am, but stability is definitely higher
north of this feature right now.

By late morning, showers will become increasingly isolated with the
North Country mainly in the warm sector of this weaker variety
system. Still high PWATs will be streaming across the region
supporting moderate to briefly heavy rain showers for the afternoon.
Convective chances will generally be isolated and tied to the front
as it tracks west to east, but any clearing will aid in
destabilizing low levels. While expected to be mostly cloudy, there
are enough cloud breaks in satellite imagery to suggest some areas
could conditionally warm enough to boost low level CAPE enough for
some heavy rainers and marginally stronger thunderstorms. Therefore,
have included a mention of small hail and potential for heavy rain
during max heating hours with any cells just ahead of the front -
roughly 2-7PM across northern New York and Western/Central Vermont.

Precipitation chances diminish behind the front tonight and
Wednesday, but kept some chances of showers with relatively mild
temperatures and upslope flow continuing. Temperatures will range
from the 40s overnight into the upper 50s/low-mid 60s for Wednesday.

&&

.SHORT TERM /THURSDAY/...
As of 329 AM EDT Tuesday...An weak shortwave drops down into the
region from Canada on Wednesday night into Thursday, leading to some
showers, particularly in northern areas. Overall, QPF should be
minimal with under a tenth of an inch expected. The showers will
move out in the afternoon and there should at least be a little
clearing. 925 mb temperatures generally will be between 8-12 celsius
and as the showers move out, the boundary layer should eventually
mix that high. This would support highs in the 60s to possibly lower
70s. There should be a decent north to south temperature gradient as
well as there will be lower 925 mb temperatures and more
showers/clouds to the north.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 329 AM EDT Tuesday...Brief ridging builds in on Friday, leading
to dry weather and a few breaks in the clouds. The ridge looks to
break down on Saturday as an occluded front makes its way into the
region and brings some rain. There is still high model uncertainty
with the details of its passage so kept PoPs mostly chance for now.
Right now, the most likely scenario looks to be the front moving
slowly across the region and bringing only some scattered showers on
Saturday. Overall, the front should be falling apart as it moves
through and the QPF looks quite unimpressive, with less than a third
of ensemble members even bringing a quarter inch of rain to any part
of the region. A few members are suggesting that a low will develop
along the front and enhance the rainfall but those solutions
currently look to be the outliers. The trailing cold front looks to
move through around Monday and it may bring a few more showers.
Despite several fronts moving through during the time period,
temperatures look to be relatively consistent. Highs should
generally be in the 60s to around 70 while lows should generally be
in the 40s and 50s.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
Through 12Z Wednesday...An elongated line of thunderstorms
stretching southwest to northeast is moving towards RUT with
tempo TS 12-14Z. Lightning, small hail, and gusts less than
30kts are primary threats. Elsewhere, conditions are calmer with
more stable showers across northeastern Vermont that will move
off of EFK into its vicinity through 15Z. CIGs will begin to
lower in earnest 15-20Z as cloud cover increases with LCLs
fairly low. Heating this afternoon may create more thunderstorms
especially in portions of northern New York and central/southern
Vermont. Then, along/behind the front CIGs will continue to
lower with no appreciable dry air to scour low level moisture.
MVFR chances continue through 03Z, then IFR CIG potential
increases for all terminals. RUT may keep some southeast flow
overnight which could favor a delay in lowering CIGs, but the
weakening pressure gradient suggests potential for IFR by 6z.

Outlook...

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

&&

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

&&

$$
SYNOPSIS...Boyd
NEAR TERM...LF
SHORT TERM...Myskowski
LONG TERM...Myskowski
AVIATION...Boyd