510
FXUS61 KBTV 031121
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
621 AM EST Tue Mar 3 2026
.WHAT HAS CHANGED...
As of 155 AM EST Tuesday...
No significant changes
&&
.KEY MESSAGES...
As of 155 AM EST Tuesday...
1. Snow this evening and tonight.
2. Light Precipitation Thursday night into Friday
3. A period of light freezing rain is possible Friday night
into Saturday, especially east of the Green Mtns, which could
produce localized slick travel.
4. The potential for ice jams and hydro related issues will
need to be monitored this weekend due to much above normal
temperatures and significant snow melt.
&&
.DISCUSSION...
As of 155 AM EST Tuesday...
KEY MESSAGE 1: A weak southern stream low passes through this afternoon
and into tonight, bringing a round of light widespread
precipitation. Despite no cold high to the north, there will be just
enough lingering cold air for it to fall as mostly snow, though it
will be on the wet side. While temperatures will be above freezing
at the onset for many of the lower elevation areas, wet bulbing will
cause the temperatures to drop and the precipitation to start as
snow. The changeover line looks to stay over southern New England or
far southern Vermont. There will be a good FGEN band on the onset
that should cause briefly heavier rates but it will pass quickly to
the east. Lots of dry air on the onset will cause virga but the
precip will eventually saturate this layer. Overall, it will bring 1-
3 inches across central and southern areas and below an inch near
the international border. After the steady precipitation moves out,
some lingering low level moisture will cause the chance of freezing
drizzle. However, this saturated layer only looks to be 1,000-2,000
feet deep so it is on the shallow side. Therefore, anything looks to
be light and scattered and at most there would be a hundredth of two
of an inch of ice accumulation. Most of this low-level moisture
looks to scatter out late in the night and early Wednesday morning.
KEY MESSAGE 2: A weak system tracks northeastward through the region
late Thursday night into Friday. It will be running directly into a
cold high trying to build southeast out of Canada. Right now, the
center of the high looks to be too far east to keep the system to
the south, but close enough to provide enough surface cold air to
cause some wintry precipitation. The current most likely scenario is
that there is a notable warm nose Thursday night that causes the
precipitation to start as a mix of rain and freezing rain. The warm
nose looks to slowly erode during the event and it should eventually
transition to more of a rain/snow mix by the end. This system will
also be on the light side. The high begins to exit east on Friday
and the cold air leaves with it for awhile.
KEY MESSAGE 3: WPC days 4 thru 7 weather grids indicate a period of
light freezing rain is possible on Friday night into Saturday
associated with initial surge of waa lift/moisture. WPC indicates
temps in the mid 30s wider valleys, but upper 20s/lower 30s east of
the Greens and portions of the northern SLV, supporting the threat
for freezing rain. An advisory level event is possible, given
marginal temps and modest qpf/ice accumulation expected. Strong llvl
waa prevails on Saturday associated with progged 850mb jet of 50 to
60 knots from the southwest, which helps to advect 925mb temps btwn
7C and 10C. WPC`s highs for Sat show values in the upper 40s to
lower 50s, but if more mixing occurs with some breaks, several areas
could approach 60F, especially southwest downslope areas of the
northern and eastern Dacks, some slightly cooler air possible near
the frozen Lake Champlain shoreline. Also, feel winds will need to
be increased over WPC values, as their forecast shows 30 knots over
Mt Marcy/Dacks and Greens on Saturday associated with a 50 to 60
knot jet at 4500 feet, which is too low. GFS did suggest some
elevated instability upstream over the eastern Great Lakes on
Saturday morning associated with the robust warm air advection
profiles, which may produce a rumble or two of thunder. However,
probability is too low attm to place in weather grids by WPC.
KEY MESSAGE 4: The latest WPC forecast for Sunday into early next week
continues to show much above normal temps with highs in the mid 40s
to mid 50s, while lows hovering either side of freezing. Given
the duration of very warm temps, I anticipate much of the snow
pack below 1500 feet will be gone by early next week, which
combined with some intervals of precip wl cause rises on rivers
and streams. These rises could be enough to produce localized
ice jams and some hydro related issues. In addition, both the
NAEFS and GEFS indicate Ausable, Mad, and Otter Creek have a 40
to 60% probability of reaching minor flood stage due to the
combination of snow melt and qpf by early next week. We will
continue to monitor the potential for both ice jam and main stem
river flooding as we head toward the upcoming weekend. Some
cooler air may try to impact our region at times by early next
week per latest GFS solution, but latest forecast grids by WPC
show temps upper 40s to mid 50s on Monday and Tuesday with lows
in the upper 20s to mid 30s.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
Through 12Z Wednesday...High pressure will result in clear
skies and light winds thru 18z today, before clouds thicken and
lower toward 21z. A band of light snow will overspread our
central and southern TAF sites between 21z-03z this evening.
Expect sharply falling vis to IFR with cigs trending toward mvfr
by 00z. As low level moisture increases areas of IFR cigs and
mvfr vis redevelop toward 06z Weds. Patchy areas of freezing
drizzle wl be possible at SLK/MPV between 04z and 10z Weds. Wind
become south/southeast with localized gusts up to 20 knots at
BTV/RUT and mostly southwest at MSS, before becoming light again
this evening.
Outlook...
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. NO SIG WX.
Thursday Night: Mainly MVFR, with local VFR possible. Chance RA,
Chance SN.
Friday: MVFR. Chance RA, Chance SN.
Friday Night: Mainly MVFR, with local IFR possible. Chance RA,
Chance FZRA.
Saturday: Mainly MVFR, with areas IFR possible. Likely RA.
&&
.EQUIPMENT...
The KBTV ASOS has suffered a communications failure. The issue
has been diagnosed, but there is currently no estimated time of
return to service. The affected communications line is not
serviced by the NWS. Terminal Aerodrome Forecasts will continue,
but regular observations may not be available.
NOAA Weather Radio station WXM-44, transmitting from Mt.
Ascutney, Vermont, on frequency 162.475 MHz is non- operational
at this time. NWS technicians have diagnosed the problem, but
repairs will likely not be able to occur for quite some time due
to circumstances beyond our control. Therefore, the time of
return to service is currently unknown. The following NOAA
Weather Radio transmitters may be able to provide service during
this outage: WWG 50 from Burke Mtn, VT at 162.425 MHz and WNG
546 from Hanover, NH at 162.525 MHz.
The Colchester Reef meteorological station is out of service.
This site is not serviced by the NWS and there isn`t an
estimated return to service at present. Please contact us if you
observe winds significantly deviating from the recreational
forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Myskowski
DISCUSSION...Taber/Myskowski
AVIATION...Taber
EQUIPMENT...NWS BTV
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