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620
FXUS61 KBTV 170732
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
332 AM EDT Tue Sep 17 2024

.SYNOPSIS...
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Unseasonable warmth continues through Thursday before a cooling
trend brings temperatures back to around seasonal averages.
Low chances of showers return with a weak frontal passage
heading into the weekend before high pressure returns early next
week.
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&&

.NEAR TERM /THROUGH WEDNESDAY/...
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As of 321 AM EDT Tuesday...No major shifts have occurred in the
expected evolution of the weather pattern over the next 36
hours. High pressure will remain firmly in control keeping
conditions very dry and temperatures above seasonal averages.
The one difference will be an increase in high clouds that will
help knock a couple degrees off the high temperatures; generally
ranging in the upper 70s to mid 80s today and Wednesday. Cloud
cover tonight may help keep temperatures a little milder than
recent overnight lows. Morning fog in climatologically favored
locations remains a good bet today and tomorrow morning.
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&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
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As of 321 AM EDT Tuesday...The pattern remains dry, though
there`s a brief shake up. A weak upper low will briefly meander
overhead bringing some mid-level clouds Wednesday night into
Thursday morning. Forecast guidance suggests that there could be
some clouds initially that gradually thin. So the extent of
radiational cooling and fog may not be quite as great, but still
included fog in the typical locations. Overnight lows will
mainly range 50 to 60 still. Despite the upper low, we likely
will not be able to develop much, if any, precipitation due to a
surface low developing well off the Atlantic and advecting low-
level dry air to its north back into our area. Greater cloud
cover and lower thicknesses will yield slightly cooler highs
compared to recent days in the mid 70s to lower 80s.
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&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
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As of 321 AM EDT Tuesday...The upper low will continue to
meander through the region into Saturday. Again on Friday, there
is an ever so slight potential for some rain. The GFS forecast
sounding does suggest that a capping inversion is breakable and
there should be some surface based instability, but the air will
remain rather dry. A back door cold front will shift
southwestwards during the day, and that may provide just enough
of a spark. We`re talking 10-20% chances of rain at best despite
this. By Saturday night into Sunday morning, the backdoor cold
front will have swept through and a new dome of high pressure
will establish itself once again. The location of the center of
this new deep layer high is positioned such that we should hold
onto cooler conditions. So we`ll trend back towards seasonal
norms for the latter half of September, which are high
temperatures in the upper 60s to mid 70s in the day and about 40
to 50 degrees at night. I think I spy an opportunity for rain
sometime for the middle of next week, but we`ll see how good my
sight is. There`s a strong upper trough or upper low poised to
approach James Bay, but that Greenland block is still looking
pretty tough (2-3 standard deviations above normal).
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&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
Through 06Z Wednesday...Calm winds and clear skies are
providing ideal conditions for fog formation again. LIFR/IFR fog
is already occurring at SLK with MPV the next most likely spot
for fog. MSS has bounced around tonight from IFR to VFR with a
light return to LIFR conditions by 9Z. EFK is the next location
with chances of fog mainly 08-11Z. For BTV, fog has formed in
the Winooski Valley and will drain down the river valley
adjacent to the airfield; drainage wind flow at BTV has been
more southeasterly, but will need to watch for any further shift
out of the river valley to see if fog will advect over the
terminal. Otherwise, light variable flow will return after 12Z
as fog burns off and high clouds increase. More fog is probable
after 03Z Thursday.

Outlook...

Wednesday: VFR. Patchy BR.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Saturday: Mainly VFR, with local MVFR possible. NO SIG WX.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.

&&

$$
SYNOPSIS...Boyd
NEAR TERM...Boyd
SHORT TERM...Haynes
LONG TERM...Haynes
AVIATION...Boyd