345
FXUS61 KBTV 161139
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
739 AM EDT Thu Apr 16 2026
.WHAT HAS CHANGED...
As of 242 AM EDT Thursday...
While high-res modeled ingredients for severe storms look more
favorable today, the stationary frontal boundary is located
farther south than anticipated, which could make it difficult
for the expected instability and warmth to materialize this
afternoon for central Vermont. Based on this, no major changes
to the thunderstorm forecast this afternoon, but have included
the mention of gusty winds in the forecast with stronger storms.
Confidence has also increased for some fog, mist, and/or
drizzle tonight, similar to last night.
&&
.KEY MESSAGES...
As of 242 AM EDT Thursday...
1. Rounds of showers expected today after fog and low clouds
lift this morning, with heightened thunderstorm chances across
southern Vermont this afternoon and evening. Please stay weather-
aware and have a method of receiving Watches and Warnings.
2. Additional showers, mist, drizzle, and fog may make for
hazardous travel again tonight, then the boundary finally clears out
of our area Friday. Please use caution when driving in low
visibilities.
3. Rainy and windy weather is expected for the latter half of
the weekend as another frontal system impacts the region.
Brief mountain snow is possible late Sunday into Sunday night
with a cold frontal passage.
4. Much colder but dry to start next week, though trending
warmer with chances of rain by mid next week.
&&
.DISCUSSION...
As of 242 AM EDT Thursday...
KEY MESSAGE 1: A stalled frontal boundary located across the southern
portion of our forecast area this morning is bringing light showers,
mist, drizzle, low clouds, and patchy dense fog this morning in
light winds and abundant moisture. Visibilities are poorest (1/4 to
2 miles) across the northern tier of our forecast area, north of the
boundary. Later this morning, after showers move out of the region
and fog gradually mixes out, we anticipate a dry period ahead of our
next low pressure system, and the stationary boundary is expected to
shift northward, drawing warmer air into the northern New York and
Vermont. in southern and central Vermont, as well as portions of the
Adirondacks and southern Champlain Valley, there should be some
areas of clearing, allowing temperatures to rise into the 70s (well
above seasonal averages), with highs in the 60s remaining closer to
the international border and on mountains. An area of low pressure
will ride along the frontal boundary this afternoon and evening,
bringing multiple rounds of showers. The HREF continues to be
aggressive with instability in the southern Champlain Valley and
southern Vermont with about 65-85% chance of 500+ J/kg CAPE and 45-
65% chance of 1000+ J/kg CAPE as dew points are expected to rise to
around 60 F. NAM3K also shows most unstable CAPE/MUCAPE at around
1600-1800 J/kg, which could assist in the production of hail. One
fly in the ointment for severe development is that the stationary
boundary may not make it very far north in time for the main forcing
to come through this afternoon, which could have us underperform in
warmth and instability. However, HREF mean 0-6 KM shear continues to
look dynamic with 45-60 knots, and 0-1 KM SRH between 70-220 m2/s2
and 0-3 KM SRH between 180-310 m2/s2 also support this. NAM3K
suggests Effective Bulk Wind Difference around 55-60 knots. Due to
the favorable ingredients, isolated to scattered severe storms are
possible across southern Vermont. The main threat would be damaging
winds, though large hail is possible as well. Due to the relatively
fast motion of the storms, flash flooding is not expected despite
modest projected precipitable water values around 1.20-1.40".
KEY MESSAGE 2: Another night of showers, mist, drizzle, and fog is
likely tonight as the front sinks back southward across the forecast
area. One thing we`re not seeing as much of tonight is a strong
atmospheric inversion trapping moisture that was present this
morning. However, the moisture (precipitable water values 1.00-
1.50") looks to linger, and models continue to suggest at least a
minor inversion setting up for a portion of tonight. Temperatures
tonight will also be largely similar to last night, with lows in the
upper 40s and 50s, fairly mild for this time of year. On Friday, the
frontal boundary haunting the region with moisture looks to finally
shift southwards and into the Atlantic Ocean by the end of the day.
This means dramatically decreasing chances of showers and
temperatures remaining above normal with highs in the 60s and lower
70s.
KEY MESSAGE 3: Low pressure will slide by well to our north Saturday
and Saturday night, dragging a cold front along in its wake.
Temperatures will warm on a 50-55 knot southerly 850 mb jet ahead of
the front, allowing highs to rise into the 60s and lower 70s.
Efficient mixing will bring windy conditions Saturday afternoon into
the overnight as the core of the jet moves overhead. Southerly gusts
of 20 to 30 mph are likely Saturday and Saturday night, with locally
higher gusts possible in the Champlain Valley due to channeling and
along the northern slopes of the Adirondacks due to downsloping. The
cold front is expected to move through late Saturday night into
early Sunday, resulting in temperatures at their warmest Saturday
evening, then falling slowly throughout the day Sunday in brisk
westerly winds after the frontal passage. Rain showers are most
likely Saturday evening through Sunday morning, coming to an end
from west to east Sunday evening and night as drier air flows in
following the frontal passage. As the showers end, they may change
over briefly to snow showers as temperatures fall into the 20s and
lower 30s Sunday night. Little to no snow accumulation is expected,
particularly below summit levels, as the atmosphere should dry out
quickly before temperatures fall too low.
KEY MESSAGE 4: Following a cold front on Sunday, a cooler and drier air
mass will filter into the region for the start of next week with
perhaps some snow shower chances on Monday. Brisk northwest flow
will draw cooler and drier Canadian air as high pressure begins to
shift east out of the Great Lakes. A trailing shortwave on the
backside of a departing trough will shift south on the leading edge
of the high with a few chances for snow showers in the higher
terrain. With 925mb temperatures Monday to -5C to -9C, sfc highs
will struggle to reach 40 areawide, with the higher terrain hugging
the freezing mark. The GFS model progs the 520dam line to sag south
into the Mohawk Valley of New York and southern Vermont further
supporting cold surface temperatures and cool enough mid level
atmospheric profiles to support a saturated thin DGZ. Snow growth
will be limited, however, due to a low equilibrium level to 700mb
and a significantly dry low level. Any snow showers that do form
will likely fall as virga for most of the region, outside of the
higher summits.
Towards mid week, model agreement decreases rapidly with the
placement of several troughs associated with an upper low. Though,
do anticipate some increasing precipitation chances as moisture
returns to the area with temperatures on the cool side.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Through 12Z Friday...Low clouds across the region will slowly
improve this morning back to MVFR and eventually VFR for most
terminals by midday. Low clouds will remain until 14-16Z based
on satellite and model soundings, as well as persistence from
yesterday. Beyond the morning low clouds, a weak surface low
will bring additional chances for rain and rumbles of thunder
into this afternoon/evening with winds becoming south/southwest.
A broken line of showers appears likely between 18-23Z across
much of northern New York, and between 22-02Z for the Champlain
Valley and much of Vermont. Within this line, a couple scattered
thunderstorms will be possible, mainly impacting RUT/MPV with
lower confidence at BTV/PBG/SLK. The main threats will be strong
gusts and some isolated large hail. Winds outside of any
thunderstorms should remain light (< 10 knots) today, with a few
breezes (10-15 knots) within the line of showers. Showers will
taper off beyond 02-03Z tonight with a return of fog and mist as
the stationary boundary lingers over the region. A return to
MVFR/IFR conditions areawide, with better confidence in
terminals receiving heavy rain, is expected.
Outlook...
Friday: MVFR/IFR conditions possible. Chance SHRA.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: MVFR/IFR conditions possible. Likely SHRA.
Sunday: Mainly MVFR, with local IFR possible. Likely SHRA.
Sunday Night: Mainly VFR, with areas MVFR possible. Chance SHSN,
Chance SHRA.
Monday: Mainly VFR, with local MVFR possible. Slight chance SHSN.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Storm
DISCUSSION...Storm/Danzig
AVIATION...Danzig
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