646
FXUS61 KBUF 041807
AFDBUF

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

.SYNOPSIS...
A weak frontal boundary will drop to near the New York and
Pennsylvania State line by this evening. A humid airmass along
with the nearby frontal boundary will bring the threat for a
shower or thunderstorm for some tonight into Friday. Another
system will bring more showers and thunderstorms Friday night.
Building high pressure will bring cooler and less humid
conditions for the weekend.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A weak cold front will continue to drift south across the region
through this afternoon, eventually settling near the New
York/Pennsylvania state line. There is a chance for a shower near
the state line this afternoon, but with the axis of deeper
moisture and instability south of the region would expect this
activity to be isolated at best. Therefore, the expectation is
that the region will be dry through this afternoon, but still
remaining very warm and humid with most high temperatures in the
lower to mid 80s, with a few upper 80s across the Genesee
Valley and Finger Lakes.

Weak surface high pressure will settle across our region tonight,
with fair, but muggy weather. The lack of a decent pressure gradient
will result in light winds for this evening...slowing firework smoke
dissipation.

The lack of forcing with the weak surface high nearby will keep much
of the region dry tonight. However there is still plenty of moisture
within the boundary layer, and there are some hints that this
mornings MCS over KS/MO may eject a subtle shortwave over our region
tonight. Energy from this feature, along with weak instability of
100 to 200 J/KG could lend to a late spot shower or two, across
far western New York.

It will remain muggy and warm tonight with lows in the mid to upper
60s common. Some patches of fog are possible with dewpoints not much
lower than the air temperature.

&&

.SHORT TERM /6 AM FRIDAY MORNING 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 /18Z THURSDAY THROUGH TUESDAY/...
VFR flight conditions will prevail into much of tonight. A weak
frontal boundary will drop across the region this afternoon,
stalling near the New York/Pennsylvania state line. Any showers
this afternoon and evening along the front will likely stay
just south of KJHW - KELZ.

Convective complex moving out of the Ohio Valley may bring some
scattered showers or an isolated thunderstorm after 04z tonight
which may linger across the region through Friday morning. Low
confidence in how this area of precipitation impacts the region.
Humid airmass in place along with light winds tonight could bring
some fog if enough clearing takes place, but confidence is low so
left fog out of the airfield forecasts for now.

Outlook...

Friday...Mainly VFR with increasing chances for showers and
thunderstorms.
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...
A passing frontal boundary, followed by weak surface high pressure
will result in a weak pressure gradient across the lower Great
Lakes, with light winds and waves through tonight.

Winds will shift out of the east Friday, then an enhanced southwest
flow will develop across the lower Great Lakes with a period of
Small Craft Advisory headlines possible.

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...TMA
NEAR TERM...Thomas/TMA
SHORT TERM...EAJ
LONG TERM...EAJ
AVIATION...TMA
MARINE...TMA