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FXUS61 KBUF 240727
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
327 AM EDT Fri May 24 2024

.SYNOPSIS...
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High pressure and a ridge building into the region will provide for
fair dry weather through tonight. A few rounds of showers and
thunderstorms are expected for portions of the holiday weekend,
including on Saturday and Monday. High pressure and a ridge will
quickly cross the region on Sunday, resulting in dry weather.
Showers and thunderstorms on Monday will linger into the middle of
the week. Above normal daytime temperatures through the holiday
weekend will cool to near or below normal by the middle of the new
week.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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Currently, mostly clear skies across the area other than a few
bands of high cirrus clouds pushing north into NY from a system
well to the south of the region. Temperatures are in the mid 50s
to near 60 for most areas.

Today, can expect another beautiful spring day with comfortable
humidity levels and warm temperatures. An elongated area of high
pressure and increased ridging from the Great Lakes will keep dry
weather in place. Afternoon highs in the mid 60s to near 80 from the
higher terrain east of Lake Ontario to the lower elevations of WNY &
the Western Finger Lakes. The warmest temperatures can be expected
for areas south of Lake Ontario where warm air advection today will
increase afternoon highs from Thursdays values. Dewpoint
temperatures today in the upper 40s to around 50 will make for
comfortable conditions. Cloud cover should be minimal resulting in
mostly sunny skies across the entire area, though some fair weather
cumulus clouds will be possible during the afternoon.

Tonight, the fair dry weather continues into tonight as a ridge axis
tracks into the area through the night, centering on the forecast
area by daybreak on Saturday. An approaching warm front will start
to increase mid-level clouds toward daybreak on Saturday, with
clouds increasing from west to east. Temperatures tonight will be in
the mid 40s to the mid 50s from the higher terrain east of Lake
Ontario to the lower elevations of far WNY respectively.
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&&

.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
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While the axis of a relatively flat shortwave ridge will be centered
over our forecast area Saturday morning...the ridge and its
associated weak sfc high will exit to our east during the afternoon.
This will quickly be followed by a pair of frontal systems that will
be pushed through our region by a robust shortwave that will track
from Lower Michigan to Lake Huron. Our dry fair weather to start the
long holiday weekend will be temporarily brought to an end...as some
showers and scattered thunderstorms will make their presence known
during the course of the midday and afternoon.

The airmass in the wake of the initial warm front will quickly
become unstable...as SBCAPE values are forecast to climb to near
1500 j/kg with a little GOMEX moisture prompting Td`s to surge to
near 60 with PWAT values increasing to near 1.5". This will combine
with forecast 0-6km shear values in the vcnty of 25 kts ahead of a
cold front to encourage some of the expected thunderstorms to become
organized enough to produce some gusty winds/hail...or to at least
support locally heavy downpours.

Showers and  leftover thunderstorms Saturday evening will taper off
from west to east as the aforementioned cold front and deep
plume of GOMEX moisture will push across New England.

Sunday then PROMISES to be the NICEST day of the Memorial Day
weekend...as a burgeoning shortwave ridge and associated sfc high
will cross the Lower Great Lakes. We can be guaranteed that sunshine
will dominate our skies...while temperatures and humidity levels
will be at comfortable levels. If you`re planning outdoor activities
for the long weekend...this will definitely be the day to do it.

Conditions will then SIGNIFICANTLY deteriorate for the remainder of
the holiday weekend.

An anomalously deep sub 995mb storm system over the Upper Great
Lakes Sunday night will have a warm that will extend southeastward
across Ohio and western Pennsylvania. A 40-45kt low level jet
impinging upon this boundary will combine with a divergent upper
level flow to supply the forcing needed to generate a blossoming
area of showers and thunderstorms over the western counties during
the second half of the night. This will be a bad premonition of
things to come for Monday as we close out the weekend.

The deep area of low pressure over the Upper Great Lakes Sunday
night will continue to track northeast on Monday...moving from
southern Ontario to western Quebec. Its associated warm front should
make its way through our region before the system occludes...so that
means that an ensuing cold front will follow on its heels for the
afternoon. While the warm front will be responsible for fairly
widespread shower and thunderstorm activity early in the day...a
moisture rich environment (PWAT`s ~ 1.75") in the warm sector behind
the front will nearly guarantee moderately heavy showers at times
for the midday and afternoon. Thunderstorms that will almost
certainly develop in the warm sector ahead of the cold front will
contain very heavy rain and could also be strong enough to generate
damaging winds. All in all...Monday could be a very active day.
Otherwise Monday will be a muggy day with Td`s forecast to climb
well into the 60s.

The aforementioned cold front will push off to our east Monday
night...thus sweeping the deep moisture and forcing out of our
region. This will allow the bulk of the residual showers and evening
thunderstorms to taper off from west to east overnight.
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&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
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While the vast majority of this period will be rainfree...it is
guaranteed to be cooler than normal with passing showers from time
to time. The culprit for the change back to Spring-like weather will
be a deep longwave trough that could possibly briefly close off in
the vcnty of the Lower Great Lakes or New England. Timing of the
associated shower activity will be difficult at best from this
range...largely due to shortwaves that will rotate through this
evolving longwave pattern.

In regards to temperatures...while the mercury could reach close to
70 for some areas on Tuesday...there is high confidence that all
zones will experience readings in the 60s for Wednesday and
Thursday. Mins will largely be in the 40s for both of those nights.
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&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
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VFR conditions expected early this morning through today as a sfc
high and increased ridging continues today. Some afternoon fair
weather cumulus may develop, but cats expected to remain at VFR.

Tonight, VFR conditions continue through the night. Some increasing
mid-level clouds toward daybreak on Saturday morning will start to
increase the potential for some CIGs, but cloud bases should remain
in the VFR levels.

Outlook...

Saturday...VFR/MVFR with scattered to numerous showers and
thunderstorms developing.

Sunday...Mainly VFR.

Monday...Restrictions likely with showers and thunderstorms.

Tuesday...Restrictions likely with showers.
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&&

.MARINE...
High pressure will build into the region through the day today with
light to moderate winds prevailing...along with waves at or below 3
feet. Generally remain light to modest winds and minimal waves will
then continue through most of the weekend as a weakening trough
crosses the area on Saturday...followed by high pressure moving back
into the region Sunday. The above said...the passing trough could
produce some showers and thunderstorms capable of locally higher
winds and waves Saturday.

&&

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

&&

$$

SYNOPSIS...SW
NEAR TERM...SW
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...SW
MARINE...JJR/TMA