FXUS61 KBTV 140207
Area Forecast Discussion
National Weather Service Burlington VT
1007 PM EDT Thu May 13 2021
Seasonably warm days with sunshine and scattered afternoon showers
and an isolated rumble of thunder will persist from Friday through
Monday, with better chances of thunderstorms on Sunday.
Generally quiet and pleasant weather is expected for the middle
of next week as a ridge of high pressure establishes itself
over the region.
.NEAR TERM /THROUGH FRIDAY NIGHT/...
As of 1005 PM EDT Thursday...As previously mentioned, SHRA
activity weakening and moving toward ME/NH and far NE VT with
basically a sprinkle. Fcst is in good shape with no changes.
Early Evening discussion...Already the loss of daytime heating
and a very dry airmass in place across the CWA and along the
international border will combine to have shower activity in
Quebec lessen with time. Current -shra activity near Montreal
will weaken as it progesses into the CWA with a brief spronkle
or just virga. Second activity about another 3-4 hours away
appears a bit more vigourous but timing away from daytime
heating will have the same effect. This activity is likely for
the NEK VT if it survives. Some slight downward trends in POPS
and coverage, otherwise forecast is in good shape.
Afternoon Discussion...A cluster of weak showers currently near
Montreal will continue moving southward and should near the
International border early this evening. There is a small window
for these showers to grow prior to waning low-level
instability. Temperatures ahead of these showers have warmed
into the upper 60s in most areas with dew points having dropped
into the upper 20s to low 30s. Therefore, showers will be high-
based and some will initially result in virga. This environment
supports a few showers to grow just tall enough for a brief
downpour with winds gusting up to 35 MPH, and a rumble of
thunder is possible with some of the earlier activity from near
Ellenburg, NY eastward to near Island Pond, VT. Otherwise, the
evening should be relatively quiet with mainly in increase in
clouds and a few showers descending through much of the northern
half of the North Country before ending by early morning.
Somewhat higher moisture air will be entering the region, which
will help make for a milder night even with winds going calm
again. Lows in the 40s will be common.
For tomorrow, an upper-level ridge will still be just to our
west keeping us in northwest flow aloft that will promote
instability aloft. As a result, while the weather generally will
be quite pleasant, the introduction of surface heating with
warm and slightly more humid conditions will be marginally
supportive of another round of isolated to scattered showers,
with slightly higher thunderstorm chances than in recent days.
The latest convective allowing model data highlights the area
from the eastern Adirondacks to the Green Mountains for best
chances of showers and a slight chance of a thunderstorm.
Similar to earlier in the week, these showers will be small and
move steadily from northwest to southeast and tend to diminish
after dark quickly. Temperatures will rise quickly into the mid
and upper 60s across most of the area, with highs topping out
in the low 70s in most locations of the Connecticut, Champlain,
and St. Lawrence Valleys.
The upper-level ridge axis finally is poised to move over the
area Friday night, resulting in mild and quiet weather. A modest
pressure gradient associated with a weak surface front will
promote southerly low-level flow that should result in
particularly mild conditions in the Champlain Valley, where
temperatures will bottom out near 50 degrees, with lows near 40
in many areas where the boundary layer should decouple resulting
in a strong surface inversion and similar cool conditions as
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
As of 335 PM EDT Thursday...Overall, little change has been made to
the weekend forecast that we`ve been highlighting the past few
days. Have opted to trim back chances for showers on Saturday
though as models have slowed the arrival of a weak shortwave
trough with general ridging over the forecast area through most
of the day. Could see a few showers from some developing cumulus
but should be pretty isolated with the best chances being in
the St. Lawrence Valley just before sunset as the shortwave
approaches. Temps will be very pleasant in the upper 60s to mid
70s for highs. Any afternoon/evening showers will quickly wane
Saturday night with quiet conditions for the remainder of the
night. Better chances for convection develop Sunday on the tail
end of the aforementioned shortwave exiting the region. Forecast
soundings show the best boundary layer instability we`ve seen
in days developing in the afternoon helping to support the
development of scattered showers and some isolated rumbles of
thunder. Temps once again will be in the upper 60s to mid 70s.
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 335 PM EDT Thursday...Heading into next week we`re starting to
see a little better consensus amongst global models where for Monday
the region remains in northwest flow and a trailing weak shortwave
could kick off a few additional showers. Thereafter trends are
towards drier conditions with a northern stream trough trending to
stay to our north, while another boundary remains to our south on
Tuesday. Broad ridging follows for Wednesday and Thursday with dry
and warm conditions persisting.
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Through 00Z Saturday...Continued VFR conditions through the TAF
period. Any convective clouds will have bases above 7000 feet
with a diminshing shower threat near the border through 06z with
no visibility restrictions. Earlier gusty winds have abated and
will be generally less than 5 kts overnight.
Aft 12z Fri, similar to today with some instabilty clouds and
sct -shra or two, especially for Northern VT. Winds will
primarily be WNW at 5-8 kts but some gustiness to 15-18 kts due
to steep low level lapse rates. VFR conditions prevail.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Slight chance SHRA.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. Chance SHRA, Slight chance TSRA.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. Chance SHRA.
Monday Night: VFR. Chance SHRA.
Tuesday: Mainly VFR, with local MVFR possible. Chance SHRA.