552
FXUS61 KBUF 210657
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
257 AM EDT Fri Jun 21 2024

.SYNOPSIS...
While it will still be uncomfortably warm and humid through this
weekend...a frontal boundary oscillating back and forth over our
region will support enough cloud cover and some thunderstorm
activity to suppress the dangerously high heat indices.
Unfortunately...the daily thunderstorms will carry the risk of
torrential downpours and even severe weather. Notably cooler and
more comfortable conditions can then be expected next
week...especially during the latter half.

&&

.NEAR TERM /THROUGH TONIGHT/...
Generally quiet night but muggy and mild with dwpts in the 60s. Lows
will be found in the 60s to low 70s by sunrise. There will be
some fog...especially in the S. Tier valleys.

A weak slow moving frontal boundary will slowly drop southeast into
and through the area today. While there will be some measure of
showers and thunderstorms with this boundary, overall coverage
appears to be limited right now. That said...have placed the best
coverage (higher PoPs > 50%) across the S. Tier (closer to the NY/PA
line) and into the Genesee Valley/western Finger Lakes region. This
is supported by most Hi-res guidance. It is also highlighted by SPC
with a MRGL risk for severe storms. We should see most of the
activity today occur with peak heating. Given PW values of 1.5-1.7
inches and short MBE vectors torrential rain will be possible with
any of the stronger cells. Highs today (a few degrees cooler) will
be found in the 80s to near 90F in spots.

Tonight...most convection should slowly wane with the loss of
daytime heating. The weak east to west frontal boundary to our south
is also advertised to return back north as a warm front. We
could see a few showers or even a thunderstorm as it returns.
Otherwise...mild and muggy night with lows in the 60s to low
70s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
Most models show a weak shortwave passing by to the north which
would cause the front to meander a bit during the day Saturday.
The North Country should stay on the cool side of the boundary.
The shortwave is likely to generate some showers with its
passage, but there`s a lower risk of thunderstorms in the North
Country. For the Western NY, a lot depends on the timing of the
shortwave with lower chances for showers and thunderstorms if it
passes in the morning and greater chances if it`s in the
afternoon. High temperatures will range from the upper 80s near
the Pennsylvania border to the upper 70s in the North Country.

Strengthening low pressure tracking across the central Great Lakes
will lift the front back to the north, putting the entire forecast
area in the warm sector. The warm and moist air mass will support
small chances for showers and thunderstorms across Western NY with
showers and storms likely across the North Country which will be
closer to the boundary and any disturbances that track along it.

A 995mb surface low and robust shortwave tracking to our north will
result in a windy day on Sunday with 850mb winds increasing to about
45 knots. This will push a strong cold front across the area which
is likely to produce some thunderstorms with its passage. There will
be ample wind shear in place to support organized convection with
damaging winds possible. Timing will be key, with model consensus
bringing the front through slightly earlier than ideal to produce
storms in far Western NY, with greater risks for storms closer to
Central NY. But this could change in future model runs. Even without
convection it will be windy across the Niagara Frontier where wind
gusts of 45 mph can be expected.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A cold front will slide east of our area Sunday night, with
lingering showers and thunderstorms tapering off from west to east.
This will be followed by a potent shortwave which will dig across
northern New England on Monday. This will bring increasing chances
for showers and a few thunderstorms across the North Country with
low chances elsewhere which will be further from the disturbance. It
will also be notably cooler and less humid with highs on Monday only
in the 70s.

High pressure will move across the region Monday night and Tuesday,
resulting in rain free and cooler weather. Another shortwave will
pass by well to the north Tuesday with an associated cold front
moving across the area Tuesday night or Wednesday. This will bring
warmer weather ahead of the cold front with a chance of showers and
possibly a thunderstorm. The cold front will then usher in cooler
weather for Thursday. By Thursday highs should only be in the upper
60s to lower 70s. Did hedge below model guidance for high temps
given the cool air mass and recent warm weather included in bias
correction.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
Most area terminals will see VFR conditions. The exception to the
VFR weather could be across the western Southern Tier where some
IFR/MVFR level fog/stratus could develop.

A weak frontal boundary will sag south through the region today and
potentially support some showers and thunderstorms. This will mainly
be the case for areas south of Buffalo and Rochester during the
midday and afternoon.

Tonight...mainly VFR but there may be some fog/low status across the
S. Tier at KJHW. Low confidence, so didn`t include it in the TAF.

Outlook...

Saturday...Mainly VFR. A chance for afternoon and evening
thunderstorms inland from the lakes.
Sunday...VFR/MVFR. Showers and thunderstorms likely.
Monday...Mainly VFR. A chance for afternoon and evening
thunderstorms inland from the lakes.
Tuesday...Mainly VFR conditions expected.

&&

.MARINE...
Light winds and minimal wave action is expected to continue across
the Lower lakes through Saturday. There will be a chance of afternoon
showers and thunderstorms which could produce gusty winds and higher
wave action each day.

A cold front will approach the region Sunday with increasing southwest
winds which may bring a period of SCAs to area lakes. Northerly
flow behind the front will then bring continued choppy conditions
to the lakes through Monday. High pressure builds in late Monday with
diminishing winds and waves for Tuesday.

&&

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

&&

$$

SYNOPSIS...AR/RSH
NEAR TERM...AR
SHORT TERM...Apffel
LONG TERM...Apffel
AVIATION...AR
MARINE...AR