000
FXUS61 KBTV 020525
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
125 AM EDT Thu Jul 2 2020

.SYNOPSIS...
Overnight, patchy fog will be possible given ample low level
moisture. Heat and humidity briefly builds in Thursday with
highs in the upper 80s to low 90s. A cold front will cross
through the area late Thursday into Thursday night with a few
additional showers and storms, followed by seasonably warm
summer weather for the upcoming holiday weekend.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 1019 PM EDT Wednesday...Only adjustment was to increase
high temperatures for Thursday in accordance with model trends.
Highest temperatures will be in the low to mid 90s likely
within the Saint Lawrence and Champlain valleys. The rest of the
going forecast remain in great shape! See previous discussion
below:

Previous Discussion...The quasi-stationary area of low pressure
that has been situated over the northeast for the last several
days will finally begin it`s southward descent. We`ll continue
to see another afternoon with scattered convection. So far, rain
footprints (~1-1.5") have been significantly less than
yesterday and areas which saw a lot of rain have missed out so
far on any training storms. Again, the primary threat with any
of these storms will be locally heavy rainfall and isolated
flooding.

As high pressure begins to sink southward, skies should trend clear
overnight and with light winds expect the return of fog/low clouds
once again areawide. This should burn off by early morning with
mostly clear skies expected tomorrow as the heat begins to crank up.
925mb temperatures around 22-23C suggest temperatures tomorrow
climbing into the upper 80s to low 90s. Unfortunately, humidity will
come with the heat, and while we won`t quite reach heat advisory
criteria we come pretty close with feels-like temps reaching the low
90s. This heat is short-lived as a weak backdoor front sags south
out of Quebec Thursday afternoon.

Ahead and along this front, the threat for a few strong to isolated
severe storms looks plausible given ample instability around, ~1000-
1200 J/kg and bulk shear around 25 kt. Main threat will likely be
heavy rainfall and gusty winds as PWATs are fairly high around 1.75-
1.9" and soundings show some mid-level dry air along with fairly
steep low level lapse rates. Expect storms to fire around 2-4 pm
across northern NY and the International Border and move southward
into central/southern portions of VT by early evening. Overall
coverage of storms should be fairly scattered therefore have only
offered 20-30% PoPs as the day won`t be a total washout.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
As of 323 PM EDT Wednesday...Expecting 850mb thermal ridge to
settle south of the region following frontal passage Thursday
night. It appears that continued shortwave troughs in prevailing
mid- level nwly flow will bring additional chances for showers
and isold thunderstorms, especially across the Adirondacks into
s-central VT for Friday afternoon. May see the warmest
temperatures across the St. Lawrence Valley and northern
Champlain Valley (80-85F) while variable cloud cover and better
chances for rainfall keep central/s-central VT in the 75-80F
range. Highest PoPs (50-60% range) expected across
Rutland/Windsor counties during the mid-late afternoon hours.
Expecting some patchy dense fog for Friday night, with lows
mainly in the upper 50s to lower 60s.

Drier air gradually filters into the region Friday night into
Saturday, with PW values falling from 1.5-1.6" Friday afternoon to
around 0.75" at 18Z Saturday. Should set up a pleasant Independence
Day with dry conditions, mostly sunny skies, and highs in the low-
mid 80s. Sea-level pressure gradient is relatively flat, so
anticipating surface winds W-NW around 5 mph.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 323 PM EDT Wednesday...Mid-summer conditions expected
through the long-term forecast period with a gradual increase in
temperatures and humidity. Temperatures begin in the mid 80s on
Sunday, but building thermal ridge ewd from the Great Lakes
should yield valley highs in the upper 80s to near 90 for the
Monday through Wednesday period. Diurnal chances for
afternoon/early evening tstm activity exist. May see more
widespread threat of showers and thunderstorms toward Wednesday,
especially per 12Z GFS with approach of a mid-level shortwave
trough from the Great Lakes and associated surface cold front.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Through 06Z Friday...A mix of flight conditions through sunrise
due to areas of dense fog and light winds. Fog and IFR/LIFR
conditions most prevalent at KMPV and KPBG through 11/12Z, with
only modest confidence at KRUT/KSLK. Elsewhere, including BTV,
VFR to prevail overnight. After 12Z VFR expected as light
south/southwest flow around 5 kts, trends northwesterly by
afternoon. Approach of weak cold front from the north may spark
a few/sct t-storms which may affect northern terminals after
22Z. While an isolated threat, brief gusty winds will be possible
with any stronger cores with localized turbulence and tops to
450 AGL.

Outlook...

Friday: Mainly VFR, with local MVFR possible. Chance SHRA.
Friday Night: VFR. Slight chance SHRA, Patchy BR.
Independence Day: VFR. NO SIG WX.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. Chance SHRA, Chance TSRA.
Sunday Night: VFR. Slight chance SHRA, Slight chance TSRA.
Monday: VFR. Chance SHRA, Slight chance TSRA.

&&

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

&&

$$
SYNOPSIS...LaRocca
NEAR TERM...Hammond/LaRocca
SHORT TERM...Banacos
LONG TERM...Banacos
AVIATION...JMG