NWS Area Forecast Discussion

000
FXUS61 KBUF 162328
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
728 PM EDT Wed Jun 16 2021

.SYNOPSIS...
High pressure centered over the Upper Ohio Valley will provide our
area with beautiful weather through Thursday. Conditions will
deteriorate Friday afternoon and night when a slow moving cold front
will make its way across the Lower Great Lakes. There will be the
potential that some of the storms could be rather strong.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
High pressure centered over the Upper Ohio valley will promote
beautiful weather tonight and Thursday. The only issue could be
very localized areas of frost in the normally colder Southern
Tier valleys and in the Black River valley and foothills of the
Adirondacks late tonight. Coverage should be very minimal and
duration not expected to be significant enough (hour or so) to
warrant a frost advisory. Some fog will also be possible in the
Southern Tier valleys.

the surface high will move off Mid Atlantic coast Thursday
night, so a resulting southerly flow will support warmer
weather with somewhat higher humidity.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Friday will likely start off dry, especially for eastern portions of
the area. Conditions will begin to deteriorate from west to east
through the morning as surface high pressure slides off the Mid
Atlantic coast and the influence of upper level ridging begins to
wane. Shortwave energy and an associated warm front will begin
pushing into WNY by the late morning, though there still remains
some discrepancies on the exact timing of these features and
therefore precipitation onset time. Surface dewpoints will climb
into the lower 60s as the system draws moisture northward into the
eastern Great Lakes and northern Ohio Valley by late Friday into
Friday night.

This will set the stage for a growing risk of convection moving into
the evening hours Friday. The timing of the approaching cold front
still remains in question, but general consensus remains for an
arrival later in the night which may overtake an unstable airmass
expected to be still in place. A LLJ passing overhead will allow 0-
6km bulk shear values to climb to over 50 kts, with model soundings
indicating CAPE values up to 1500J/kg. This will bring at least some
severe weather potential Friday evening and through the overnight
hours. SPC has placed a marginal risk of severe weather across all
of western and north central New York.

With the larger scale trough still hanging over the region, some
lingering showers and thunderstorms will be possible during the day
Saturday and into Saturday night. Highs on Friday and Saturday will
be a few degrees warmer than previous days, topping out in the mid
70s to low 80s areawide.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Sunday will be dry before the next potential for rain. An area of
low pressure will track northeast across the Great Lakes and into
Quebec on Monday, causing increased POPs starting early Monday
morning for WNY. As this sfc low tracks northeast, its widespread
shield of rain will approach and go mostly over and north of Lake
Ontario, but the southern and eastern portion of the area of showers
will overspread WNY. As the sfc low tracks northeast, the trailing
cold front will cross the area, extending the potential for showers.
As the area of low pressure takes a more northerly oriented track,
the frontal passage will slow down some over the area, increasing
the potential for a more prolonged shower/rain event. Some guidance
is suggesting, with the slower frontal passage, an additional wave
of low pressure will track northeast along the boundary, bringing
the potential for another round of rain Tuesday morning continuing
through most of the day. High pressure over the center of the
country should start to approach the region on Wednesday, providing
a dry day.

Temperatures during the long term period will be in the upper 70s to
mid 80s Sunday and Monday. Behind the passing front, temps on
Tuesday and Wednesday will drop to the mid 60s over the higher
elevations to the low 70s for the lower elevations.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Widespread VFR conditions are expected through the entire TAF
period. High pressure building across the area will provide dry
weather right through tonight. Winds will become light and
variable overnight. The only weather to speak of will be the
potential for some patchy river valley fog to form across the
interior Southern Tier late tonight into early Thursday morning.

Outlook...

Thursday night...VFR.
Friday and Friday night...Showers and thunderstorms becoming likely
with MVFR conditions at times.
Saturday...Mainly VFR with a chance of showers and thunderstorms.
Sunday...VFR.
Monday...VFR to MVFR with the likelihood for showers and
thunderstorms.

&&

.MARINE...
High pressure will build southeast across the lower Great Lakes
through Thursday. SCA criteria winds/waves across the eastern
half of Lake Ontario should subside overnight.

After a brief period of lighter winds Thursday, the pressure
gradient will tighten Thursday night and Friday in advance of an
approaching cold front. This will bring the next period of
freshening winds and waves on the Lakes, with choppy conditions
expected to last through at least the first half of the weekend.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Beach Hazards Statement until 2 AM EDT Thursday for NYZ005-006.
MARINE...Small Craft Advisory until 2 AM EDT Thursday for LOZ044-045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH/Zaff
SHORT TERM...PP/TMA
LONG TERM...SW
AVIATION...RSH/Zaff
MARINE...JM/SW

NWS BUF Office Area Forecast Discussion