206
FXUS61 KBTV 200024
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
824 PM EDT Wed Aug 19 2026
.WHAT HAS CHANGED...
As of 220 PM EDT Wednesday...
No significant changes were made to the forecast.
&&
.KEY MESSAGES...
As of 220 PM EDT Wednesday...
1. Showers are expected to continue this afternoon and evening
before drier and seasonable weather returns as we head into the
weekend.
2. Showers and thunderstorm chances increase by the end of the
weekend with unsettled weather continuing into early next week.
Temperatures will be relatively seasonable through the extended
period.
&&
.DISCUSSION...
As of 220 PM EDT Wednesday...
KEY MESSAGE 1: A dying cold front is approaching northern New
York and Vermont from Canada this afternoon, producing some
showers out ahead of it. The forcing will decrease as it moves
east through northern New York, but enough instability is out
there to allow the showers to continue into Vermont. A couple
embedded thunderstorms are possible as well. While sufficient
deep layer shear will be in place for potentially strong storms,
low instability, some dry air aloft, a lack of well-defined
surface boundary, and pre-existing clouds/showers will be
working against it. Therefore, an isolated strong to severe
storm is not likely this afternoon, but cannot be completely
ruled out. Any storms will fall apart as they try to push
southeast this evening and southern areas should remain mostly
dry. Chances of lingering showers overnight are around 10-40%,
mainly near the international border. High pressure will build
down from Canada to end the week and start the weekend, bringing
cooler temperatures and lower humidity. Lows tonight will be
seasonable in the 50s, then cooling late week into the 40s and
50s. Highs through Saturday will be seasonable, with
temperatures rising into the 70s and low 80s each afternoon.
Next chance of precipitation arrives later Saturday afternoon
onward.
KEY MESSAGE 2: A quasi-double barrel pattern will develop by
late Saturday with competing pieces of energy, one over central-
eastern Ontario, and a coastal low in southern New England.
Models depict a deepening trough over the Great Lakes by
Saturday with a coastal low riding along the coast of southern
New England. The deepening of the Great Lakes trough will help
amplify our flow pattern aloft Saturday night into Sunday,
likely accelerating the coastal low northeastward. A few showers
will be possible on the periphery of the coastal low Saturday
night in southeastern Vermont, though majority of Vermont will
stay dry Saturday and Saturday night. In northern New York, the
Great Lakes trough will lead to increasing shower chances late
Saturday into Saturday night across the St. Lawrence Valley and
northwestern Adirondacks. Questions linger on how much moisture
will be sandwiched between the two systems closer to Sunday
morning, as it pertains to precipitation chances in Vermont.
Currently there is a 35-50% chance of rain Sunday morning for
much of Vermont, though these values may increase or decrease
with how the trough amplification occurs. A more delayed
amplification could keep the coastal system from racing east
with a moisture interaction in the area between the system
Sunday morning. A faster amplification will likely lead to less
system interactions and perhaps a dry Sunday morning.
Regardless, as the Great Lakes trough translates east Sunday,
everyone will see periods of rain, and perhaps some
thunderstorms should enough clearing take place to allow
instability to grow. Temperatures will start off on the warmer
than average side in the upper 70s to low 80s, though with the
approach of clouds and showers, temperatures by Sunday will
begin a gradual decrease back to seasonable levels.
The main piece of energy departs late Sunday, though cyclonic
flow about a trailing upper low over eastern Ontario will keep
some shower chances around. Lingering showers will be focused
over the higher terrain Monday and Tuesday afternoon, mainly
diurnally driven. Sky cover Monday and Tuesday will favor more
clouds then sun as a result of the scattered shower chances.
Temperatures will remain on the seasonable to potentially
slightly below seasonable levels Monday and Tuesday with highs
in the low to mid 70s. Temperatures will rebound by mid week
with subtle ridging building over eastern New England.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Through 00Z Friday...Isolated showers with some rumbles of
thunder are tracking along the international border close to
MSS. Thus far the storms have stayed north of the terminal. MSS
and EFK will have possible showers through about 03z. Otherwise,
drier conditions are expected overnight, but BR/FG will be
possible once again especially any terminals that had rain
today. Brief MVFR visibilities are possible in any showers that
occur. As the front washes out over the area, lingering low
level moisture remains for the overnight. The question then
becomes does this moisture scour out in the mid levels for fog
potential, or does this low level moisture remain fairly thick
with more low level stratus. Regardless, most sites will likely
see some reductions at least to MVFR cigs and vsby tonight with
moisture lingering. Models depict some easterly flow at BTV
which could draw some VCFG at the least near sunrise. Highest
probabilities for fog (around 40-50%) exist at SLK/MPV, with
slightly lower probs (30-40%) at MSS/EFK. Trends upstream
suggest low stratus may initially spread over the area
transitioning to more fog closer to sunrise. Any low clouds
scour out by tomorrow morning with mainly high clouds through
the end of the TAF period. Winds will become light and variable
overnight into the morning.
Outlook...
Thursday Night: VFR. Patchy BR.
Friday: VFR. NO SIG WX.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Slight chance SHRA.
Saturday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, Chance TSRA.
Sunday: Mainly MVFR, with areas VFR possible. Definite SHRA,
Chance TSRA.
Sunday Night: Mainly VFR, with local IFR possible. Slight chance
SHRA, Slight chance TSRA.
Monday: Mainly VFR, with local IFR possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Storm
DISCUSSION...Storm/Danzig
AVIATION...Neiles
|
