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087
FXUS61 KBUF 180611
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
211 AM EDT Sat May 18 2024

.SYNOPSIS...
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A few showers or an isolated thunderstorm will continue to be
possible today. Dry weather returns areawide tonight which lasts
through Tuesday. It will also become unseasonably warm with
temperatures climbing well above normal. Unsettle weather returns by
mid-week and turning progressively cooler.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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Showers and pockets of drizzle will begin to diminish overnight into
this morning as low-level forcing weakens and the deeper moisture
exits off to our east. Low cloudiness and some pockets of fog will
linger for part of the morning hours but some measure of clearing
will take place by this afternoon. This will allow for limited
instability to build with advertised 300-700 J/kg. With lingering
moisture and effects from the trough we could see a few showers or
even a thunderstorm develop this afternoon. The best chance to see a
shower or storm will be found across Western NY (Southern Tier), and
along any subtle boundary. Highs today will be found in the 70s for
most locales.

Tonight...any lingering showers will quickly diminish with the loss
of daytime heating. After that...generally quite and dry weather
will take hold. That said...with lingering low-level moisture due to
the recent rains some fog formation will be possible overnight.

Otherwise...a pleasant night is expected with lows found in the 50s.
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&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
Little change in MSLP Saturday. Surface high pressure remains along
the east coast with variable winds across the forecast area. Ridging
will build into the forecast area as the shortwave trough moves into
the Capitol Region Saturday. Daytime heating and low level moisture
will likely lead to diurnal showers and an isolated thunderstorm,
mainly across interior western NY or along a lake breeze boundary.
Highs will reach the low to mid 70s.

Saturday night will begin a period of dry and warm weather
across western and north central NY.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
A high amplitude upper level ridge will be entrenched along the
spine of the Appalachians and into New England to start the period.
With the ridge axis centered along the eastern side of the CWA, the
surface high pressure center itself will slowly wander from being
centered over the western end of Lake Erie on Monday toward the east
coast on Tuesday. As a result of the gradual progression, weak
southerly (or even southeasterly) flow on Monday afternoon will to a
stronger southwesterly flow on Tuesday and Wednesday. With the
eastward slumping of the surface ridge and increasing momentum off
the deck from Monday through Wednesday, surface to 850 hPa mixing
should increase and allow for strong afternoon run ups in
temperatures with interior sections from the Genesee Valley eastward
easily jumping into the mid 80s while even most of the lakeshores
approach 80F during this interlude as select guidance has 850 hPa
temperatures running up to +16 to +18C. The only places in the CWA
that may reach their thermal apex on Monday rather than Tuesday or
Wednesday seem to be the Niagara Frontier and the Watertown areas,
where the south/southeasterly flow would keep any lake-influenced
air out of the picture. With stronger southwesterly flow on Tuesday
and Wednesday, these areas may hold back a few degrees relative to
their more interior peer locations.

While all will seem bright and sultry early next week, don`t dare be
fooled that summer is here as things go way off the tracks shortly
thereafter. A massive pattern shift looks to be in store for the
second half of next week. The semi-resident ridge will slide off the
east coast with an upstream closed 500 hPa low ever-so-slowly
ejecting from the Rockies toward the upper Great Lakes. Several
successive short-wave troughs with associated reinforcing shots of
cooler air will push through the region beyond Wednesday as a
result. This will lead to steadily increasing chances of showers
with temperatures falling back substantially from where we will have
been by that juncture. In fact, while the forecast features a
consensus of wildly disparate guidance numbers by the end of next
week and the upcoming Memorial Day holiday weekend, there are
several fairly reliable pieces of guidance in the mix that would
suggest some drastically colder conditions will be in the mix by
that time. Evidence of this can be gleaned from the +4C at 850 hPa
on the ECMWF and +3C on the Canadian global by Sunday, as well as
the -3C on the GFS Friday morning. While each of these numbers by
themselves doesn`t mean a whole lot, when we approach the Friday
through Sunday period as a whole, it would certainly tend to lean
toward the belief that a portion of it is likely to be significantly
colder than we have been accustomed to.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
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Showers will gradually weaken but low-level moisture will bring at
times IFR-LIFR cigs and vsbys to area terminals overnight into this
morning. There will also be pockets of fog with lower vsbys,
especially at KJHW.

A few showers or even an isolated thunderstorm will again be
possible this afternoon across Western NY. Mainly focused across the
Southern Tier, and along any subtle boundary. Elsewhere...mostly dry
with VFR flight conditions.

Tonight...any lingering showers will diminish with the loss of
daytime heating. There will be some fog possible overnight which may
bring some impacts with LIFR-IFR conditions.

Outlook...

Sunday through Tuesday...mainly VFR.

Wednesday...VFR-MVFR. A chance of showers and thunderstorms.
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&&

.MARINE...
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Light winds with minimal wave action expected on the lakes through
Monday. South winds develop and begin to pick up by Tuesday as a
cold front near the eastern Great Lakes but conditions will likely
remain below small craft levels. The next chance at small craft
conditions may materialize by midweek as low pressure sends a cold
front through the lakes.
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&&

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

&&

$$

SYNOPSIS...AR
NEAR TERM...AR
SHORT TERM...HSK
LONG TERM...Fries
AVIATION...AR
MARINE...AR