708
FXUS61 KBTV 210650
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
250 AM EDT Sun Jun 21 2026
.WHAT HAS CHANGED...
As of 249 AM EDT Sunday...
No major changes to the forecast with this update.
&&
.KEY MESSAGES...
As of 249 AM EDT Sunday...
1. Rounds of showers will continue today, bringing an
additional 0.20-0.60 inches of rainfall, potentially more in heavier
or repeated showers and storms.
2. A steadier soaking rain is expected to move from west to
east through New England Monday into Monday night, mainly impacting
our southern counties but with the potential to track further north.
3. Mostly dry conditions late Weds into Thurs, followed by more
unsettled and active weather late week into next weekend.
&&
.DISCUSSION...
As of 249 AM EDT Sunday...
KEY MESSAGE 1: A vertically stacked low pressure system is located over
the Gulf of St. Lawrence and Newfoundland, Canada, this morning. It
is currently swinging a shortwave through northern New York and
Vermont, resulting in continued showers early this morning. In the
last 24 hours, the Champlain Valley, Greens, and northwestern
Vermont have reported between a quarter of an inch and an inch of
rainfall with higher amounts just over the border in Quebec. Over
the next 6 hours, we anticipate showers chances 15-55%, highest on
northern and western slopes of the mountains. Precipitation chances
then increase towards noon and the early afternoon today as
instability increases and temperatures head towards the upper 60s
and 70s. Shower and thunderstorm chances will be around 30-70%
today, with highest confidence in the Champlain Valley and the Green
Mountains. As previous forecaster stated, severe winds and hail are
not expected with these storms, though briefly moderate to heavy
rain is possible. Additional rainfall amounts of 0.20-0.60" are
likely today into the evening, with potential for higher amounts in
any heavier shower or thunderstorm as modeled precipitable water
values run as high as 1.00-1.25". If these heavier storms occur over
an area that already has saturated soils from previous rain, this
could mean localized ponding or isolated flooding, especially if
these areas get repeated showers or thunderstorms, but the potential
for these issues is much lower today. At this point, no rivers are
forecast to go into flood stage over the next few days, though this
could change if precipitation amounts locally exceed our current
forecast.
KEY MESSAGE 2: Upper level closed low pressure currently in western
Ontario is expected to track eastward into Quebec on Monday while
another low pressure system and open wave currently in the Rockies
track through the Ohio Valley Monday, sending a wave of
precipitation into the Northeast. Deterministic model spread seems
to have only increased in the latest runs. The GFS has shifted its
track more southward and lowered precipitation in our forecast area,
while the Canadian has generally stayed the course but increased
precipitation amounts (and sharpened the gradient of precip on the
northern edge), and the NAM12 model has brought the track more
northward and increased precipitation amounts. Most noticeable
trend about the NAM3 is that is has largely slowed down arrival
of precipitation to the area. Current thinking has up to a
quarter inch of rain Burlington northwards and 0.25-1.00" of
rain south of Burlington, with highest amounts in southern
Vermont. These higher amounts could reach north of Burlington if
the storm tracks farther north, resulting in higher amounts
than forecast in southern Vermont. On the other hand, the areas
south of Burlington could see lower amounts if the storm ends up
tracking farther south, and areas along the international
border could even see little to no rain. This more southern
track is looking the least likely as the southernmost-leaning
models seem to be holding steady from run to run. Most likely
scenario sees some measurable precipitation in the Adirondacks,
central Champlain Valley, Winooski River Valley, and southward,
with more uncertainty along the international border. At least a
half an inch of precipitation is likely in Rutland and Windsor
counties of Vermont. Temperatures will trend back towards
seasonal normals for the first half of the work week, with
widespread highs in the 70s to lower 80s and lows in the upper
40s to around 60 F, and drier weather is anticipated to follow
this Monday-Monday night system into the midweek.
KEY MESSAGE 3: Mid/upper lvl trof remains acrs the Great Lakes into the
NE CONUS for days 4 thru 7 with minimal change in our thinking.
Initially fast west to east zonal flow is evident in the upper air
analysis for Weds into Thurs with some lingering mtn showers
possible on Weds aftn. Weak 1016mb high pres should keep most of the
area dry into Thursday. By Thurs into Friday our next s/w drop
southward acrs the Great Lakes and mid/upper lvl trof amplification
is progged. This wl help advect deeper moisture and some instability
back into our region late Thurs into Friday with an increase in
areal coverage of showers and thunderstorms expected. Initially pw
values are near 1.0" ahead of weak sfc trof reflection, while deep
layer moisture may limit sfc heating/instability and how robust
convection can become on Friday. Also, mid/upper lvl flow remain
progressive from the southwest, before shifting to the west by late
Friday, should help to minimal any flood threat.
Meanwhile, latest progs for next weekend shows additional s/w energy
with higher pw values surging toward the NE CONUS, as boundary is
progged to be draped acrs our cwa. Pw values climb to near 1.5" with
potential for a convective cluster of showers and storms to impact
our region. Of course this far out, exact placement of heaviest qpf
and track of system is impossible to fcst, but ingredients looks
favorable for some areas of heavy rainfall possible. Progged 925mb
btwn 15-17C support highs mid 70s to lower 80s for Thursday and
Friday, with some slightly cooler readings possible by next weekend.
Little change in lows with values mid 50s to mid 60s.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Through 06Z Monday...Scattered showers persist across our region
this morning with a mix of MVFR and VFR conditions at our taf
sites. Thinking the MVFR cigs at SLK will become IFR in the next
1 to 2 hours and prevail thru 14z, before improving. Elsewhere,
thinking mostly MVFR cigs prevail at EFK with VFR at PBG/BTV/MPV
and RUT with brief MVFR cigs possible in any shower activity.
Also, did note on the FAA webcam at RUT some very shallow ground
fog on the southwest perspective, so have placed BCFG few002 to
cover this potential. Given southeast winds 3 to 5 knots,
thinking fog coverage at RUT should be limited. Additional
scattered shower activity is expected on Sunday, which will be
covered with PROB30 groups in the next 12z taf package. Light
and trrn driven winds under 6 knots this morning, become
northwest at 4 to 8 knots today.
Outlook...
Monday: VFR. Chance SHRA.
Monday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Tuesday: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. Chance SHRA, Slight chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Storm
DISCUSSION...Taber/Storm
AVIATION...Taber
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