528
FXUS61 KBTV 211121
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
721 AM EDT Tue Oct 21 2025
.SYNOPSIS...
Rain will taper off towards the international border as low pressure
shifts away. Seasonable weather conditions in the upper 50s to lower
60s are expected today with breezy southwest to west winds. A large
upper low will set up across the Great Lakes region, with renewed
chances for rain for the middle to latter half of the week. Dry
surface high pressure will begin to build during early next
week.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 223 AM EDT Tuesday...Surface observations place low pressure
just southeast of Montreal and radar suggests the mid-level
circulation resides somewhere near Highgate as of 2 AM. Beneficial
soaking rains has produced 0.50- 1.00" across Vermont and northern
New York and 1.50-2.50" along Greens, the northern Champlain Valley,
and northern slopes of the Adirondacks. Embedded in western slopes
of the Greens, a few sites are reporting observations as high as
~3.50" of rain in the last 24 hours. Plattsburgh has also observed a
daily record for rain for October 20th. Before low pressure shuffles
off to the northeast this morning, we could receive another few
hundredths in areas sheltered from northwest flow, but about
0.10-0.50" for most everyone else, especially northwest slopes.
Conditions will trend cooler as the upper low settles overhead and
atmospheric thicknesses decrease. Seasonable temperatures are
expected in west-southwest flow. Clouds will clear out as well for a
small portion of the day. Another upper low will begin approaching
tonight, and so rain chances will increase again heading into
Wednesday. Instability will also be present on the order of 200-400
J/kg of CAPE. With cool temperatures aloft and modest synoptic
forcing for ascent, we could see some rumbles of thunder again
during the day on Wednesday as rain showers lift north. Eastern
Vermont has the highest chances for rain as secondary low pressure
along Vermont will favor a surge of rain moving up the Connecticut
River. This system will not have the deep, anomalous moisture plume
as this last event, nor will surface low pressure linger as long. So
precipitation amounts will be more in the realm of 0.10-0.50"
Wednesday.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
As of 223 AM EDT Tuesday...The core of the upper low will sit
overhead by Thursday with sub-540 thicknesses for 1000-500mb.
Temperatures will cool to the mid 40s to mid 50s on Thursday
down to the freezing mark at summit levels. Forecast trends for
snow levels have come up, but at about 3700-4000 ft elevation,
our summits are still in line to observe their first
accumulating snow of the season while lower elevations have a
cool, showery day.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 223 AM EDT Tuesday...A deep trough will build into the region
going into the end of the week. A few shortwaves will bring more
organized precipitation at times, but the overall general trend will
be toward drier conditions. Despite the duration, amounts will be
relatively light. Persistent cyclonic westerly flow will favor the
upslope areas, but current NBM probabilities of more than a quarter
inch are only around 25 percent there. Forecast 925 millibar temps
near and slightly above freezing should cause the snow levels to
sink into the 3,000-4,000 range for Friday night. Soundings
generally indicate they could drop a bit lower. Some ADK towns could
obtain their first flakes of the year. This trough looks to be the
beginning of a more seasonable stretch. Afterwards a very strong
surface high builds into the region for the end of the weekend and
start of next week. Ridging should dominate and the next storm
system does not look to arrive until late week.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Through 12Z Wednesday...Ceilings are a mix of VFR and MVFR but they
have begun to rise and this trend will accelerate this morning. By
around noon, terminals should all be VFR except EFK. VFR conditions
are expected to persist through the evening. Ceilings will lower
again late tonight and they should trend toward MVFR by tomorrow
morning. Any lingering rain showers will exit within the next few
hours but none of them will be heavy enough to significantly lower
visibilities. Rain showers arrive late tonight and brief visibility
reductions to MVFR are possible. Winds are generally westerly and
southwesterly and they will trend to more southerly as the day goes
on. They should mostly become light and terrain driven tonight,
except BTV which is expected to keep southerly winds. Any remaining
LLWS will end within the next couple hours.
Outlook...
Wednesday: Mainly VFR, with local MVFR possible. Definite SHRA,
Slight chance TSRA.
Wednesday Night: VFR. Chance SHRA.
Thursday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Thursday Night: Mainly VFR, with areas MVFR possible. Chance
SHRA.
Friday: Mainly MVFR, with areas VFR possible. Chance SHRA.
Friday Night: Mainly MVFR, with areas VFR possible. Slight chance
SHRA.
Saturday: VFR/MVFR conditions possible. Slight chance SHRA.
&&
.EQUIPMENT...
The TYX radar is down until further notice after a hardware
failure occurred. Replacement parts have been ordered and will
be installed. There is no ETA on its return to service.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Haynes
NEAR TERM...Haynes
SHORT TERM...Haynes
LONG TERM...Myskowski
AVIATION...Myskowski
EQUIPMENT...BTV
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