030
FXUS61 KBUF 040527
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
127 AM EDT Sat May 4 2024

.SYNOPSIS...
A weakening cold front will bring some showers to parts of the
region this evening into tonight. Shower chances steadily decrease
later tonight into Saturday with just scattered showers, and also
dry time built in between the showers. Another slow moving cold
front will pass across the area Saturday night through Sunday
bringing the next round of more widespread showers and possibly a
few rumbles of thunder. High pressure then returns Monday, allowing
for a dry start to the new work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A weakening trough will continue to drift east across the area
overnight. Showers are light and very spotty, but a few sprinkles
and light showers will continue overnight.

With very little forcing in place for Saturday, expecting just
scattered showers, especially during the morning hours with a good
deal of dry time built in through the day. Next stronger cold front
will approach from the west late Saturday, while next wave moves
north from the Ohio Valley. This will help to displace the upper
level ridge east over New England, thus opening the door for the
next surge of moisture and lift to move over the area with chances
for showers increasing from south to north late in the day into the
evening. Highs will be mainly in the 60s.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The mid-level ridge axis over the forecast area through Saturday
afternoon will push east toward New England Saturday night. In its
wake, a shortwave trough will track northeast out of the OH/TN
Valleys toward WNY. As the trough approaches, shower coverage will
increase significantly from south to north through the later portion
of Saturday evening and overnight. An influx of moisture with the
trough will also help showers expand over the region. There still
remains some uncertainty with track of shortwave trough and moisture
over the forecast area with some models placing the higher rainfall
amounts over WNY and other guidance more to the east toward CNY.

An incoming cold front on Sunday morning will increase forcing over
the area, prolonging and expanding the potential for showers through
at least the afternoon hours. Still uncertainty with how quickly the
cold front tracks through the region among guidance as well with
some guidance prolonging the showers through most of the day and
into the evening on Sunday. Overall though the later portion of
Saturday evening through at least the early afternoon on Sunday
looks to be soggy for most of the forecast area. The more organized
showers on Sunday should be mainly across the eastern third of the
area by the late afternoon, with some lingering/scattered showers
across the rest of the area.

With the large scale trough just north of the region still, along
with lingering synoptic moisture, scattered showers will linger
through most of Sunday night. Drier air moving into the area along a
zonal flow will start to scatter out any remaining showers from west
to east through the late night.

Rainfall amounts of a quarter of an inch to half an inch is
expected, with some higher amounts possible as well. Current
thinking is the higher qpf amounts will be along the south shore of
Lake Ontario east to the north country. Still plenty of uncertainty
with higher qpf placement among guidance still.

A ridge building into the region will result in drier weather for
Monday through Monday night across the entire area. Clearing skies
on Monday will result in increasing sunshine from northwest to
southeast through the day. Clouds will linger the longest near the
NY/PA line as a disturbance tracks south of the area.

Temperatures on Sunday will be in the low 50s for the higher terrain
east of Lake Ontario to the mid and upper 60s for the lower
elevations south of Lake Ontario. For Monday, temperatures warm to
the mid 60s to mid 70s from the higher terrain to lower elevations
respectively.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
A sprawling mid and upper level low will start out this period over
the northern Rockies and Upper Plains states on Tuesday...then will
slowly drift eastward across the northern half of the CONUS through
the remainder of the work week. This being said...the medium range
guidance continues to exhibit considerable differences in the
strength and rate of eastward progression of this low...and
consequently also in the strength/timing of a number of shortwave
impulses ejecting eastward from this system and across our region.

With the above in mind...forecast confidence in associated
precipitation potential/timing  remains fairly low particularly from
about Wednesday onward...and as such have undercut blended guidance
a bit in an attempt to better reflect this uncertainty. In general
this system should bring more unsettled weather with frequent
opportunities for showers and perhaps a few thunderstorms during the
middle and latter portions of next week...though likely also with
some drier periods interspersed.

As for temperatures...these will continue to average some 5-10
degrees above normal through this period.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
A weak trough will continue to cross the region through early this
morning with a few spotty, light showers. VFR will prevail for the
bulk of the area, although some low MVFR/IFR stratus may develop
across the higher terrain of the Southern Tier for several hours
around daybreak. Some of this may impact KJHW.

There will continue to be a few spotty showers today, but much of
the time will be rain free as the trough washes out overhead. VFR
will prevail with a wealth of mid level clouds.

Another wave of low pressure will move from the Ohio Valley this
evening across the eastern Great Lakes tonight. This will bring a
period of fairly widespread rain spreading from southwest to
northeast across the area from late evening through the overnight.
CIGS will deteriorate to widespread MVFR/IFR shortly after the rain
begins, and any pockets of moderate rain will bring short term VSBY
restrictions. A 40+ knot low level jet will also produce some low
level wind shear overnight.

Outlook...

Sunday...Widespread MVFR/IFR in the morning in rain. Improving to
mainly VFR from west to east in the afternoon and evening as the
rain tapers off. Chance of a few widely scattered thunderstorms in
the late afternoon and evening across Western NY.

Monday and Tuesday...VFR.

Wednesday...VFR/MVFR. Chance of showers with a slight chance of
thunderstorms.

&&

.MARINE...
Mainly weak pressure gradients are expected to persist into this
weekend across the lower Great Lakes supporting winds to generally
remain below 15 knots. Expect this to bring some choppy waters at
times, however conditions will remain below headline criteria,
especially with an offshore flow developing tonight then persisting
through the weekend, keeping the highest waves over Canadian waters
for Saturday and Sunday. While quiet weather continues for the end
of the work week, a few showers and thunderstorms will be possible
tonight through Sunday. High pressure will build across the area for
the start of the new work week providing mainly gentle breezes with
no more than some light chop expected through Tuesday.

&&

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

&&

$$

SYNOPSIS...AR/JM
NEAR TERM...AR/Hitchcock/JM
SHORT TERM...SW
LONG TERM...JJR
AVIATION...Hitchcock
MARINE...AR/JM