FXUS61 KBTV 042320
Area Forecast Discussion
National Weather Service Burlington VT
720 PM EDT Wed Aug 4 2021
Fair, seasonable weather will persist through Friday under
surface high pressure. An isolated shower or storm will be
possible across the northern mountains this afternoon and again
on Thursday afternoon, but generally dry weather is expected
under passing mid to high level cloud cover. A better chance of
more scattered showers and storms arrives over the weekend with
the approach of a weak front. Prevailing conditions will trend
warm and muggy with daytime shower activity.
.NEAR TERM /THROUGH THURSDAY NIGHT/...
As of 625 PM EDT Wednesday...For the evening update, have just
made some minor adjustments to the temperatures and dew points
over then next few hours as we are seeing slightly drier and
warmer conditions right now. Have also made some added in some
overnight fog in the favored locations east of the Greens to
include the Connecticut River Valley. Cloud cover could greatly
impede any formation overnight, but hi-res model data leans
towards a few hours of clearing, enhancing chances of fog
formation. Previous discussion follows...
Quiescent conditions persist with some haze which is starting
to shift north and away. Temperatures range from the low 70s to
near 80 with light and variable winds. A narrow band of cirrus
is over the northern Adirondacks, which was the area that had
the greatest potential for a brief shower or stray thunderstorm.
As noted in visible satellite, the cumulus field is diminished
beneath the cirrus canopy. Perhaps something could briefly flare
up near the edge of the cirrus line, but we may see convection
fail to fire and have reduced PoPs accordingly. Lows generally
in the 50s tonight.
No change expected tomorrow. A tunnel of rich moisture lies to our
east, and it should waffle somewhat westwards as the Bermuda High
strengthens. It looks like precipitation will creep right up to the
Vermont-New Hampshire border and then fail to make it westward.
Viewing forecast soundings, available instability is lackluster,
even over high terrain. It should be mostly dry, and another
perfect weather day added to the tally with only a stray
mountain shower could take place as we warm into the upper 70s
to lower 80s tomorrow. With a slight uptick in dewpoints,
overnight lows should be a couple degrees warmer in the low 50s
to low 60s.
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
As of 249 PM EDT Wednesday...Transient high pressure will build
across the North Country on Friday and will continue the recent
trend of drier conditions across the North Country. Taking a look at
temperatures at both the 925 mb and 850 mb levels, we enter this
nice warm air advection regime with our temps aloft warming 2-3
degrees. This will yield some of the warmer temperatures seen over
the past several weeks with highs slated to warm into the lower to
mid 80s region wide by Friday afternoon. Partly to mostly sunny
skies will be seen through the day but we will begin to see clouds
cover quickly stream into the region Friday night as flow aloft
shifts to the southwest and a nice slug of moisture begins to enter
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 249 PM EDT Wednesday...The first part of Saturday continues to
look dry but increasing moisture will yield increasing dewpoints and
cloud cover. Even with increasing cloud cover, temperatures aloft
will still allow temps to warm into the lower to mid 80s and
dewpoints well into the 60s. This should set the stage for decent
instability ahead of a frontal boundary dropping southeast out of
Canada. Latest ensemble tracks show a cold front sweeping into the
St. Lawrence Valley around 21Z Saturday before advancing across the
remainder of the North Country through the evening and overnight
hours. Initially, it looks like convection will be rooted within the
boundary layer but as the evening progresses, all instability
becomes elevated. This means little in terms of sensible weather as
thunderstorms will be possible through Saturday night but the
chances for any strong wind gusts associated with decaying storms
will be very unlikely once the instability becomes elevated.
Although the front appears to push through the region, we will
remain under the influence of the upper level trough through much of
the day on Sunday which will likely keep scattered showers and
isolated thunderstorms possible through the afternoon hours.
Monday has the best chance of being dry with a progressive longwave
ridge tracking over the region with synoptic scale subsidence likely
to inhibit much in terms of precipitation. However, as Tuesday comes
around, we enter a progressive upper level pattern which looks
poised to bring periods of showers to the region through much of
next week. No single day looks to be wash-out nor do we expect any
significant rainfall. However, it may be difficult to plan outdoor
and recreational activities given the showery regime we appear to be
dipping back into. Temperatures will continue to remain at or above
normal through the long term with the Climate Prediction Center
hinting that this warm spell could last the next 14 days and
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
Through 00Z Friday...VFR conditions persist across the forecast
area with light, variable winds and decreasing cloud cover. This
will remain the story through the TAF period for all terminals
except KMPV where fog may develop between 08z and 12z. There is
also a slight chance of fog at KSLK, but have left out of the
TAF for now with the better chances being across eastern
Vermont. By 13z, localized valley fog is expected to dissolve
resulting in a return to VFR conditions for all terminals for
the remainder of the TAF period. Winds will remain light and
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Chance SHRA, Slight chance TSRA.
Saturday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, Slight chance TSRA.
Sunday: MVFR/IFR conditions possible. Chance SHRA, Slight chance
Sunday Night: Mainly VFR, with local MVFR possible. Slight chance
Monday: Mainly VFR, with local MVFR possible. Chance SHRA.