-- Discussion containing changed information from previous version are highlighted. --
232
FXUS61 KBTV 110740
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
340 AM EDT Sat May 11 2024

.SYNOPSIS...
Scattered showers will develop during each of the next few
days, with northern New York seeing the most numerous showers.
Temperatures will continue to be at or below normal. The
unsettled and cooler weather continues through the middle of the
week, when a few thunderstorms possible as well.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 204 AM EDT Saturday...Main story continues to be the
Northern Lights visible early this morning in most of the
region, with convenient clearing of skies throughout
northeastern NY and much of northern Vermont. Progged relative
humidity in the 700-850 mb level coincident with the present
cloud layer is ebbing and flowing, with a slight trend towards
greater coverage of cloudy skies and then clearer skies over the
remainder of the overnight hours. Expect further adjustments to
sky cover may be needed, but overall forecast is in good shape.
Towards daybreak the most marked drying aloft is indicated in
northeastern Vermont, while overcast skies are most likely to
persist in western Franklin County and throughout St. Lawrence
County in New York.


Previous Discussion...

Diurnal heating has caused a few low-topped convective showers
to develop, but limited instability is keeping them light. The
low- level of the atmosphere is also dry so some of the lighter
ones are not even reaching the ground. As diurnal heating wanes,
the convection will quickly dissipate this evening. Tonight
should be mostly dry, except across the St. Lawrence Valley
where a few continued showers are possible. The daytime cumulus
and stratocumulus should mostly dissipate this evening,
particularly over northern areas. However, it will take longer
to for the clouds to fall apart than the showers, so it will
likely be close to midnight before skies can mostly clear. Skies
should generally be either partly cloudy or mostly clear for
the second half of the night, with the clearest areas farther
north. Lows will generally be in the upper 30s and low 40s, but
some of the colder hollows of the Northeast Kingdom could fall
into the low or mid-30s if enough clearing occurs. A shortwave
passes through the region tomorrow and the extra forcing will
bring more numerous showers, mostly across northern New York.
However, the convection will still be low topped and there will
still be very limited instability, so while some of the showers
may be heavier, thunderstorms are not expected. Temperatures
will be very similar to today, with highs between the mid 50s
and mid 60s. Another shortwave builds in Saturday night so there
is enough forcing for the showers to continue overnight,
despite the lack of diurnal heating. Overall, even though there
will be some showers for an extended period of time, QPF is low.
It is generally between a few hundreths of an inch over the
Northeast Kingdom to around a quarter inch over northern New
York.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
-- Changed Discussion --
As of 321 AM EDT Saturday...Weak riding mainly in the mid lvls
builds into our region on Sunday night, followed by a warm type
feature on Monday. Weak ridge could provide conditions favorable
for some patchy fog, but feel potential is conditional and
overall probability is <20% attm so have not placed in fcst.
Temps if some clearing can develop could drop into the lower/mid
30s coldest valleys to lower/mid 40s CPV/SLV. For Monday a warm
frnt lifts from sw to ne acrs our cwa with increasing chc for
showers. This boundary becomes stationary acrs our cwa late
Monday into Tues as it parallels the flow aloft with additional
moisture advection. Difficult to pin point exact placement of
boundary and precip given a rather complex mid/upper lvl pattern
with closed cyclonic circulation near Hudson Bay and building
SE CONUS ridge. For now have highest chc pops along the
International Border for Monday into Monday night. Temps with
clouds hold mostly in the 60s on Monday.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
-- Changed Discussion --
As of 321 AM EDT Saturday...An unsettled pattern prevails into
midweek with increasing probabilities of a widespread wetting
rainfall on Tues into Tue night. Still some guidance
discrepancies on exact placement of heaviest qpf axis
associated with stalled boundary acrs our region. Latest trends
continue to support a split flow with limited phasing btwn
northern and southern stream systems thru mid week. In addition,
have noted the NBM CAPE of 250 J/kg or greater on Tues is <10%
acrs our region, as soundings show a stable/moist adiabatic
profile with limited sfc heating due to clouds/precip. If cwa
can break out in the warm sector some instability is possible
for thunder, but trends are too low attm to mention in fcst.
Have continued with high likely pops on Tues/Tues night, which
can be increased if needed as confidence improves for a
widespread wetting rainfall. Have noted several ensemble members
showing a much more suppressed outcome, resulting in drier
conditions, similar to what unfolded on Friday acrs our cwa.
Temps hold mostly in the upper 50s to upper 60s thru Weds.
Uncertainty increases further for late week, as predictability
in complex mid/upper lvl pattern is low. Latest ECMWF shows
developing ridge over low pres type scenario, with cyclonic
circulation a bit close for comfort to have high confidence in a
dry fcst on Thurs/Friday. Meanwhile, GFS is advertising weak
s/w ridge building into our region on Thurs/Fri with drier
conditions and comfortable temps. For now have trended drier
with near normal temps, given the large spread in guidance.
Bottom line no significant or high impactful weather is
anticipated over the next 5 to 7 days.
-- End Changed Discussion --

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Through 06Z Sunday...VFR conditions will largely prevail
through the TAF period, with the possible exception of
intermittent fog at SLK early this morning. BKN/OVC in the
070-100 range will largely persist with periods of scattering
through the period. Scattered showers will develop with VCSH at
MSS where chances of showers are slightly higher than farther
east, but may see showers expand towards 00Z such that the move
over other sites. Brief MVFR visibilities will be possible
associated with the showers. Winds will continue to be light,
only peaking into the 5 to 10 knot range during the daytime and
primarily out of the south/southeast.

Outlook...

Sunday: Mainly VFR, with local MVFR possible. Chance SHRA.
Sunday Night: VFR. Slight chance SHRA.
Monday: VFR. Chance SHRA.
Monday Night: Mainly MVFR, with areas VFR possible. Chance SHRA.
Tuesday: Mainly MVFR, with areas VFR possible. Chance SHRA,
Slight chance TSRA.
Tuesday Night: Mainly IFR, with areas MVFR possible. Chance SHRA.
Wednesday: Mainly IFR, with local MVFR possible. Chance SHRA.

&&

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

&&

$$
SYNOPSIS...Myskowski
NEAR TERM...Kutikoff/Myskowski
SHORT TERM...Taber
LONG TERM...Taber
AVIATION...Neiles