019
FXUS61 KBUF 260742
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
342 AM EDT Thu Sep 26 2024

.SYNOPSIS...
Weak low pressure will drag a frontal system through the region this
morning. A few showers may linger across the Southern Tier and
east of Rochester through early afternoon, otherwise high pressure
will build across the lower Great Lakes to support fair dry weather
through at least Friday. Most, if not all of the significant
rains from Helene should stay to our south.

&&

.NEAR TERM /THROUGH TONIGHT/...
An area of weak low pressure over Quebec will drift northeast
dragging a wavy frontal boundary through the region today.
Fairly widespread rain showers across the area early this
morning ahead of the approaching surface boundary and main mid
level wave. Overall slow movement of the main mid level wave and
surface boundary will keep showers around for much of the
morning, especially from the Southern Tier through the Finger
Lakes into the eastern Lake Ontario region. Latest CAMs similar
in suggesting a gradual ending of the showers from north to
south through early afternoon. Elevated CAPE of 200-400 J/Kg
will be found within this environment, so will maintain at least
a slight chance for thunderstorms.

High pressure will build into the region behind the frontal passage.
This will keep the area dry through tonight, however the degree of
clearing is in question as upper level moisture well in advance
of Helene overspreads the region.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
An upper level ridge will be centered over the eastern Great Lakes
region while being sandwiched between low pressure over Quebec and
low pressure over the central Mississippi Valley Friday. Remnants of
Hurricane Helene will become absorbed into the area of low pressure
to the south Friday into Friday night. A plume of tropical moisture
will approach the forecast area from the south, however ensemble
means keep the axis of anomalously high PWATS south of the forecast
area through Friday which should result in dry weather. The upper
level ridge will move slowly east and allow the upper low to move
east into the start of the weekend. PWATS will increase from south
to north across the forecast area. The chance for rain showers will
be introduced across the southern half of western NY Friday night
with low chances continuing through Sunday night. Confidence remains
fairly low in the coverage and amount of rainfall due to the spread
in ensemble members. The upper level ridge axis and surface high
over north central NY will likely keep conditions mostly dry for the
eastern Lake Ontario region through Saturday night. Light east-
northeast winds will be felt at the surface.

Above normal temperatures are likely with highs in the mid to upper
70s Friday, Saturday, and Sunday and lows in the upper 50s to low
60s Friday night, Saturday night, and Sunday night.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
The longwave pattern will continue to be dynamic through mid-week,
with more unsettled weather re-emerging. By Monday, the remnants
of Helene will be circulating within the partially open, positively
tilted wave over the Ohio Valley and Mid- Atlantic states. This
could lead to a few showers across the far Southern Tier Monday,
though high pressure ridging to the north should keep conditions
mostly dry.

A sharp shortwave trough will quickly approach the region from the
Upper Great Lakes region Tuesday. Past model runs showed the
potential for this trough to phase with the exiting trough to the
south, however it looks like models have separated these systems.
Therefore, Tuesday looks mostly dry with the potential for a brief
period of ridging across the region. A strong cold front will move
through the forecast area Tuesday night through Wednesday.

While temperatures are expected to continue to average above normal
Monday and Tuesday, much cooler air in the wake of the front will
finally give us a taste of fall weather by Wednesday. Models are far
from lock and step with the depth of the cooler airmass, though
ensemble mean 850H temps are around +8C by Wednesday which should
translate to highs in the upper 50s to low 60s. This will also be
plenty cold enough to potentially spur some additional lake effect
rain showers Wednesday, though the airmass may be initially too dry
for this to be realized.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
A slow moving cold front will keep showers around this morning, with
a mix of VFR/MVFR to IFR cigs, the latter of which will be focused
across the Srn Tier.

Dry weather will return to the region by this afternoon. Cigs will
improve to VFR levels by late morning/midday, then most areas will
lose their cigs altogether by the end of the day with mainly upper
level cloud cover across the region.

Outlook...

Tonight...Mainly VFR.
Friday...Mainly VFR...but with a chance of showers across the
western Southern Tier.
Saturday through Monday...VFR.

&&

.MARINE...
Winds will gradually become southwest and then west today as a
trough crosses the eastern Great Lakes from west to east, with wind
speeds decreasing with the passage of the trough. Northeast flow
will then pick up Friday, possibly requiring small craft headlines
on Lake Erie and western Lake Ontario.

&&

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

&&

$$

SYNOPSIS...AR/RSH/TMA
NEAR TERM...TMA
SHORT TERM...HSK
LONG TERM...HSK/PP
AVIATION...AR/RSH/TMA
MARINE...AR/TMA