006
FXUS61 KBTV 111428
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
1028 AM EDT Mon May 11 2026
.WHAT HAS CHANGED...
As of 1028 AM EDT Monday...
No significant changes have been made to the forecast at this time.
&&
.KEY MESSAGES...
As of 222 AM EDT Monday...
1. Mostly dry today and Tuesday with additional frost and fire
weather concerns.
2. Widespread rainfall expected Wednesday with unsettled
weather continuing into Thursday.
3. Cool, showery conditions to persist into the weekend before
warming up.
&&
.DISCUSSION...
As of 222 AM EDT Monday...
KEY MESSAGE 1: A weak upper level trough will push across the
International border this afternoon and may spark a few light rain
showers. Antecedent dry conditions will limit rainfall totals to
less than 0.05" and will also limit far south these showers will be
able to spread. Afternoon dewpoints and RH values are expected to
dry significantly as we are able to mix into a very dry layer
extending up to 800 mb. This will likely result in RH values in the
Champlain and Connecticut River Valleys to drop between 20% and 30%
with slightly higher values expected outside of the wider valleys.
These low dewpoints will recover slightly overnight tonight but will
leave a lot of room for temperatures to drop rapidly. Widespread
lows in the mid 20s to mid 30s are expected under clear skies and
light winds which will likely support widespread frost across the
North Country and northern New York. Additional frost headlines will
likely be needed but will be issued with the afternoon issuance of
the forecast package. Tuesday will be similarly dry with afternoon
RH values in the 25% to 40% range but there will be no chances for
any showers as high pressure will become entrenched across the
region. Additional frost will be possible again Tuesday night but
will likely be tied to eastern Vermont as cloud cover moves in from
the west ahead of the next storm system.
KEY MESSAGE 2: A developing upper level trough will begin to displace
the synoptic scale ridging Tuesday night which will begin to usher in
an unsettled period of weather for the second half of the week.
Rainfall is expected to spread from west to east early Wednesday
morning with good upper level diffluence helping to maximize
precipitation rates with seasonal precipitable water values.
Rainfall totals, at this time, are forecast to be highest across
southern Vermont and the Adirondacks of New York with a quarter to
half of an inch possible with around a tenth of an inch near the
International Border. A strengthening low level jet is expected to
create some cross-barrier flow which could eat up a significant
portion of the rainfall due to downsloping. We will want to keep an
eye on this as some guidance does show the potential for 30-45 mph
wind gusts on the western slopes of the Greens with southeasterly
downslope winds but the exact track of several smaller features will
dictate how the winds interact with the Green Mountains. Unsettled
conditions will continue through the day on Thursday as the upper
level low will be directly overhead. Steep mid-level lapse rates and
broad cyclonic flow will be favorable for widespread shower activity
with a slight uptick in intensity during the daylight hours.
KEY MESSAGE 3: Model scenarios continue to trend in the direction of an
upper trough consolidating into an upper low while a weak surface
reflection develops off the coast Thursday night into Friday.
Moisture will pinwheel as these become vertically stacked. Dry air
will begin to impinge on the western hemisphere of the cyclone. So
rain chances will be higher across Vermont. The upper low will delay
the onset of warmer temperatures for just a little longer. NBM
guidance has slowly shifted towards below normal for the remainder
of the week.
However, by late Saturday into Sunday, a fast moving northern stream
system will act to displace the upper low. There could be some
precipitation moving quickly eastward associated with the zipping
vort max, but ensembles remain widely varied on its placement.
Nevertheless, an upper ridge will likely settle overhead Sunday
night into Monday. Temperatures will nudge upwards well into the 70s
by Monday. The NBM indicates roughly a 75% chance of occurrence.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
Through 12Z Tuesday...Mainly VFR conditions are expected. West to
west-northwest winds will increase 16z-22z to 7 to 11 knots
sustained with gusts 16-20 knots possible. A few isolated showers
will be possible, mainly over KSLK and KMSS about 17z-22z with
PROB30s noted at both. Cloud bases this afternoon will mostly range
between 5000-8000 ft agl, and then trending clear overnight. KSLK
has some potential for fog, but there is uncertainty with dry air.
However, if KSLK does receive some precipitation, then conditions
appear relatively favorable. For now, noted 3SM from about
08z-11z.
Outlook...
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: Mainly VFR, with local MVFR possible. Definite SHRA.
Wednesday Night: Mainly MVFR, with local IFR possible. Definite
SHRA.
Thursday: Mainly MVFR, with local IFR possible. Definite SHRA.
Thursday Night: Mainly IFR, with areas MVFR possible. Chance
SHRA.
Friday: Mainly IFR, with areas MVFR possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Danzig
DISCUSSION...Clay/Haynes
AVIATION...Haynes
|
