319
FXUS61 KBUF 042328
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
728 PM EDT Thu Jul 4 2024

.SYNOPSIS...
A weak frontal boundary will wash out across Pennsylvania tonight.
Most of the night will be dry, although a few spotty showers are
possible at times, especially across the Southern Tier. Friday will
be mainly dry and warm, with just a small chance of a few spotty
showers or an afternoon thunderstorm. Weak low pressure will then
cross the eastern Great Lakes Friday night with a better chance of
showers and thunderstorms. High pressure will then build into the
region over the weekend with slightly cooler and less humid air.

&&

.NEAR TERM /THROUGH FRIDAY/...
Radar imagery showing weak returns moving into Western NY, marking
the ascent ahead of a weak remnant MCV from earlier upstream
convection. These radar returns are high based, and an extensive sub-
cloud dry layer is keeping much of this virga. A few sprinkles or
light showers may eventually move into Western NY later this
evening, but the chance of measurable rain remains low. Otherwise, a
wealth of dense mid/high clouds continue to stream over the area,
with overcast skies through tonight.

Lower confidence forecast tonight and Friday with respect to the
timing and placement of rain chances as a weakening convective
complex over the Ohio Valley approaches the region tonight. More
organized convection will remain well south of the region within the
warm sector, but the weak remnants of the MCV may produce a few
spotty showers overnight, especially from the Southern Tier into the
Finger Lakes.

Some of the precipitation tonight may linger into Friday morning,
especially across the Southern Tier and Finger Lakes, along with a
decent amount of cloud cover. This will help keep instability at
bay, at least through the morning hours. How much the atmosphere can
recover will be important in how much convection can develop during
the afternoon with the main focus along a lake breeze or
differential heating boundary. Subsidence behind the departing MCV
and overall lack of large scale support or low level foci will keep
the chance of showers and storms quite low through most of the day.
The best chance will be across the Southern Tier and Finger Lakes,
with mainly dry weather favored on the lake plains.

Very warm and humid conditions will continue Friday with most high
temperatures in the mid 80s for lower elevations and lower 80s for
higher terrain.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
A potent shortwave trough crossing the Great Lakes region Friday
night and Saturday will support a surface low to slide northeast
across the central Great Lakes Friday night, pulling across from
west to east its cold front through the area. Ahead of the front, a
strong southeasterly flow, along with the warm temperatures from
earlier in the day will provide enough instability across the lower
Great Lakes region to make for an active start to the night with
showers and storms. This combined with the prefrontal trough,
associated DPVA, and the area aligning beneath the equatorward
entrance of the upper level jet overhead will support enough shear
for showers to support a few storms to produce a few damaging winds.
This being said, the Storm Prediction Center has placed the area
beneath a marginal risk for severe weather Friday night, with
damaging winds being the main concern.

In the wake of the cold frontal passage, Saturday will be breezy
featuring a brisk southwest wind with a few gusts across the lake
plains peaking near 30mph. Otherwise, outside of a few lingering
chances for some showers across the eastern Lake Ontario region, the
remainder of the region should be rain-free and cooler with highs in
the mid to upper 70s across western New York and east of Lake
Ontario and a few low 80s across the northern Finger Lakes.

High pressure centered over the Ohio Valley Saturday night will make
its way east-northeast across the lower Great Lakes and into New
England Sunday and Sunday night. Overall the dry weather trend will
continue featuring comfortable humidity levels and plenty of
sunshine.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Surface ridging will slide east Monday, though the dry weather will
persist. With the exiting high pressure, southerly flow will return
and therefore advect in warm moist air into the region supporting
summer-like temperatures. Highs Monday will range in the 80s.

The next mid-level trough will begin to slide across the Great Lakes
Monday night through the rest of the week. This will reinstall the
chances for showers and storms Tuesday and Wednesday. High pressure
then looks to return late in the week. This being said, timing and
tracking of the next system remains in question and things may
change.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
A wealth of mid/high clouds will continue to move across the region
overnight, with CIGS generally lowering with time. A few areas of
MVFR CIGS may develop late tonight and Friday morning across the
higher terrain of the Southern Tier near the PA state line,
otherwise VFR will prevail. A weakening area of light showers will
cross the region overnight, but the spotty/light nature of this will
keep VSBY mainly VFR.

Friday, a few showers may linger in the morning, especially from the
Southern Tier into the Finger Lakes. A bubble of drier air will then
move across Western and Central NY for the bulk of the day, keeping
the area mainly dry with VFR cloud bases. An upstream trough will
approach Western NY late in the day, with increasing chances for a
few showers and thunderstorms by early evening.

Outlook...

Friday night...MVFR with showers and thunderstorms likely.
Saturday...Mainly VFR with decreasing chances for showers.
Sunday and Monday...VFR.
Tuesday...Restrictions possible with showers and thunderstorms likely.

&&

.MARINE...
Winds will remain light tonight through Friday, generally 10 knots
or less with little wave action. A cold front will move across the
area Friday night, producing a few scattered thunderstorms with
locally higher winds and waves. Southwest winds will increase
Saturday behind the cold front, with winds and waves possibly
reaching Small Craft Advisory criteria, especially on Lake Erie.

High pressure will build into the region Sunday, reducing the
southwest flow on the lower Great Lakes. The surface high will move
east Monday with a southerly flow favored. The pressure gradient
will be light enough on both Sunday and Monday to allow for some
local lake breezes to form.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Hitchcock
NEAR TERM...Hitchcock/TMA
SHORT TERM...EAJ
LONG TERM...EAJ
AVIATION...Hitchcock
MARINE...Hitchcock/TMA