436
FXUS61 KBUF 252103
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
503 PM EDT Sat May 25 2024

.SYNOPSIS...
Lingering showers will wind down this evening as high pressure
builds into the region...bringing a return to fair weather for the
overnight hours and Sunday...when the best weather of the weekend is
expected. A complex storm system tracking across the Upper Great
Lakes will then support very unsettled weather for Monday...with
this bringing potential for some strong thunderstorms and locally
heavy downpours.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of late afternoon the main batch of pcpn attendant to a passing
mid-level shortwave is now primarily draped across areas from the
Genesee Valley eastward...and continues to steadily pull east. This
diminishing trend will continue over the next 3-4 hours...and have
sped this up in the forecast some to account for recent radar and
satellite trends. With this area of precip and associated cloud
cover also having stabilized the lower levels of the atmosphere to
the point where it is devoid of noteworthy instability...have also
largely pulled any mention of thunder that had previously been
attendant to this departing area of pcpn. Further west...the return
of some sunshine and the approach of a decaying surface trough from
the Central Great Lakes could still generate just enough weak
instability and lift to pop a few more widely separated showers
across far western New York through early this evening...however the
degree of destabilization expected here also appears unlikely to be
supportive of any additional thunder.

From sunset onward...any leftover scattered showers will continue to
end from west to east through the rest of the evening and early
overnight hours. This clearing...coming on the heels of fairly
widespread convection...could lead to some late night fog and
stratus as we push into the wee hours of Sunday morning.

Sunday...high pressure will quickly build into the region providing
clear skies and an overall fantastic day for outdoor activities.
With full sunshine on display in the afternoon temperatures should
easily peak in the mid 70s to low 80s in spots.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
The pattern become amplified as an upper level trough digs into the
Mid-Western States and Upper Great Lakes region Sunday night into
Memorial Day. A warm front that extends from surface low pressure
over Illinois will move from south to north across the forecast
area. A plume of GOMEX moisture will move into the region with PWATS
over the 90th percentile for this time of year. The first wave of
showers will be associated with the nose of a 40kt low level jet.
The showers will move through the forecast area late Sunday night
into Monday morning. There will likely be a break across western NY
Monday morning, however destablization will occur with daytime
heating and dewpoints in the mid to upper 60s. There are hints of a
prefrontal trough across western NY Monday afternoon, as well as an
approaching cold front as the surface low moves into northern lower
Michigan. Relatively strong mid-level flow will be present as a
shortwave trough becomes negatively tilted to our northwest.
Conditions are favorable for organized convection and some strong to
severe thunderstorms. This activity will then move northeast across
the Finger Lakes region and into north central NY into Monday
evening. There is a Day 3 Marginal Risk out for the area. The moist
airmass will also make for torrential downpours and isolated
flooding can`t be ruled out. Rainfall amounts may exceed an inch
especially east-southeast of Lake Ontario. There will likely be
drier air in the mid-levels across western NY which may limit
rainfall amounts.

The cold front will move across the region Monday night. Overall,
showers and storms will end from west to east across the region,
however moisture lingers behind the departing system. Showers will
remain possible into Tuesday morning. The upper level trough will
become nestled over the Great Lakes region Tuesday. A series of
shortwave troughs will round the base of the trough across the Upper
Midwest region and Ohio Valley. Cool air aloft during daytime
heating and lift from the approaching trough will support low to
medium chances for showers and a few thunderstorms across the region
Tuesday afternoon into evening. The next shortwave trough and cold
front will approach Tuesday night and support another period of
showers overnight.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
An upper level trough will be across the eastern Great Lakes region
Wednesday through Thursday. There will be multiple shortwave troughs
that rotate cyclonically around the parent low and bring periods of
unsettled weather. Thunderstorms are possible especially in the
afternoon into early evening. The trough will move east through the
end of the week and cooler air will filter into the region into
Friday. Surface high pressure will move into the region for the
weekend resulting in moderate confidence of fair and dry weather
Friday to Saturday.

Temperatures will start out below normal Wednesday and Thursday and
increase to near to above normal Friday and Saturday.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
Leftover showers from the Genesee Valley eastward will continue to
wind down from west to east through early this evening as the
supporting mid level disturbance exits our region. Behind
this...some renewed sunshine and a the approach of a decaying
surface trough could pop a few more widely scattered showers across
far western New York through early this evening...otherwise largely
dry conditions are expected there. In general flight conditions will
be VFR...with highly localized/brief MVFR/IFR possible within any
showers.

Tonight...high pressure will build into the region...bringing an end
to any leftover showers. Clearing skies and light winds will also
lead to the development of areas of fog and lower stratus...
resulting in fairly widespread MVFR to IFR conditions through
daybreak Sunday. After sunrise...renewed diurnal heating and mixing
will lead to the dissipation of any fog and low stratus that forms
overnight...leaving behind widespread VFR conditions for the rest of
the day.

Outlook...

Monday...Restrictions likely with showers and thunderstorms.
Tuesday and Wednesday...Restrictions possible with showers.
Thursday...VFR.

&&

.MARINE...
Lingering showers will continue to wind down from west to east
through the first half of tonight as high pressure builds into our
region...while winds will largely to be light to modest at 10 knots
or less. With a moist airmass in place...clearing skies could allow
for some areas of fog to develop overnight.

On Sunday the axis of the high will slide across our area in the
morning...then off to our northeast during the afternoon. This will
result in light to modest winds turning east-northeasterly under 10
knots...with fair weather prevailing outside of any areas of early
morning fog.

More notable winds will occur on Monday into Tuesday with increasing
southerly winds early Monday taking on a more west-southwesterly
component Monday afternoon into Tuesday. Winds could nudge into the
15 to 25 knots range with possible small craft headlines needed
during this time period. Scattered gusty thunderstorms will also be
possible Monday.

Boaters should continue to monitor the forecast, especially given
the holiday weekend which will likely increase boating activity.
This will especially be the case on Monday as conditions on the
lower Great Lakes will likely deteriorate.

&&

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

&&

$$

SYNOPSIS...AR/JJR
NEAR TERM...AR/JJR
SHORT TERM...HSK
LONG TERM...HSK
AVIATION...AR/JJR
MARINE...AR/JJR