Area Forecast Discussion
Issued by NWS Burlington, VT

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KBTV 180913
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
513 AM EDT Thu May 18 2017

.SYNOPSIS...
Near record high temperatures expected today, along with gusty
southwest winds, especially the Saint Lawrence Valley. The heat
will help to fuel strong to locally severe thunderstorms late
this afternoon into the overnight hours. The primary threat will
be damaging winds and one inch hail. Much cooler and drier
weather returns to the North Country on Friday into the upcoming
weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 510 AM EDT Thursday...Active weather day is on tap for
today. Pre frontal trough will approach this afternoon, followed
by a cold front overnight. Strong southwesterly flow will be in
place across the area, with a wind advisory in place for the St
Lawrence Valley. Temperatures will also approach record high
values today with upper 80s to lower 90s across the area.
Surface dewpoints climb into the 60s this afternoon with deep
layer moisture being advected into our region on the
southwesterly flow. Warm temperatures and high dewpoints will
create surface instability, Cape values will be around 1500
during the afternoon with 0 to 6 km shear 45-55 kts. Hi res
models showing first round of convection starting up around 4 or
5 pm, spreading from Essex County NY southeastward across
Vermont. Gusty winds and small hail are possible and potential
to become severe will need to be monitored. Not a lot of large
scale lift yet though, maybe a limiting factor as previous
forecaster noted. By about 8-9 pm a more organized line of
storms, strong to severe, will approach the St Lawrence valley.
With these storms the primary threat will be strong gusty
winds, possibly damaging, with very strong low level wind fields
noted. These storms will have better forcing with cold front
and accompanying surface convergence. Think that these storms
will cone through in the form of a line. Best chance for
damaging winds will be across Northern New York and edging into
the Champlain valley, but the air mass will generally be more
stable across Vermont and storms may not hold together. Have
continued with mention of enhanced wording, gusty winds small
hail and heavy rain. Wind advisory also remains in effect from
18z to 03z for the Saint Lawrence valley with strong gradient
flow out of the Southwest. Wind gusts in the 40 mph range are
expected, with wind gusts in the 30s across the rest of the
forecast area. Surface cold front continues to push across our
forecast area overnight, and should clear our forecast area by
about 12z. Lots of ingredients in place for some potentially
severe weather today, though still a bit of uncertainty with
proximity to cold waters of Lake Ontario as storms cross that
area, as well as unfavorable timing of surface cold frontal
passage. Very hot windy day for sure though with at least some
strong storms.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
As of 445 AM EDT Thursday...Last bit of shortwave energy in
upper level trof kicks across our forecast area early Friday,
showers are likely through about 18z. From Friday afternoon
through Saturday surface and upper level ridges will build over
our area, much drier and cooler air will be in place. This time
period will be much cooler than the previous 2 days, but much
closer to seasonal normals, generally highs in the 60s and lows
in the 40s. There may be areas of frost in the deeper/protected
valleys of the Adirondacks and Northern Vermont.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 435 AM EDT Thursday...The weekend will start with a ridge
of high pressure over the North Country through early Sunday.
The latter half of Sunday will see increasing chances of showers
as the surface ridge shifts east into the Atlantic. 500mb ridge
will crest over the region late Sunday, allowing for surface
front to approach from the west and produce showers and possible
thunderstorms Sunday night and Monday. The front and associated
low pressure will push east Monday night and Tuesday with
drying conditions, but remain in southwest flow and keep
temperatures near normal. A large 500mb will dig into the Great
Lakes area for the mid-week, bringing another chance for
showers.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
Through 06Z Friday...VFR conditions persist throughout the
period. Low level wind shear continues this morning before
sunrise and mixing begins to produce wind gusts of 20 to 30
kts...possibly around 40kts in the Saint Lawrence Valley during
the afternoon hours. Daytime heating and abundant moisture
likely to result in instability and rain showers during the
early afternoon. Have included VCSH at this point. Thunderstorms
may develop with these showers associated with lift of
prefrontal trough. A cold front moving across the North Country
during the evening hours may lead to more widespread showers and
thunderstorms.

Outlook...

Friday: VFR. Breezy. Chance SHRA.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. Chance SHRA.
Sunday Night: VFR. Chance SHRA.
Monday: MVFR. Chance SHRA.

&&

.CLIMATE...
Max Temp Records for 5/18/17

KBTV...89 set in 1989
KMPV...90 set in 1962
K1V4...92 set in 1906
KMSS...90 set in 1962

&&

.EQUIPMENT...
The WSR-88D at Fort Drum (KTYX) will be unavailable through
Thursday May 18, 2017. During the outage, radar coverage is
available from adjacent radar sites including Burlington (KCXX),
Albany (KENX), Buffalo (KBUF), and Binghamton (KBGM).

A new signal processor will be installed, which replaces
obsolete technology, improves processing speed and data quality,
provides added functionality, and supports IT security.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...Wind Advisory from 2 PM this afternoon to 11 PM EDT this
     evening for NYZ026-027-087.

&&

$$
SYNOPSIS...Neiles
NEAR TERM...Neiles
SHORT TERM...Neiles
LONG TERM...KGM
AVIATION...KGM
CLIMATE...WFO BTV
EQUIPMENT...WFO BTV



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.