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583
FXUS61 KBUF 021948
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
348 PM EDT Sun Jun 2 2024

.SYNOPSIS...
Low pressure will bring some rain showers to WNY today into
this evening. Low cloudiness and some areas of fog will be
possible tonight across portions of Western New York. Mainly dry
weather returns Monday but a shower or isolated shower will be
possible in the afternoon. The next chance for showers and
storms will arrive by the middle of the week.

&&

.NEAR TERM /THROUGH MONDAY/...
As a weakening low pressure system will bring some showers to our
forecast area through this evening. The best shot at seeing
shower activity will be found from the Genesee Valley west
across WNY. East of Lake Ontario...most locales likely won`t see
much other than just an increase in cloud coverage.

Otherwise...QPF amount of no more than a few hundredths of an
inch at best expected over any given location.

Highs today will be a bit cooler in the 60s to low 70 west of
Genesee Valley due to cloud cover. Elsewhere...highs will be in the
mid to upper 70s near 80F where there will likely be more sunshine.

Tonight...light winds and residual moisture following what little
rainfall we do receive will allow for low stratus and some patchy
fog overnight. Otherwise...lows will range through the mid 50s to
around 60.

Monday...mainly dry weather as weak mid-level ridging builds into
the region. That said...an isolated shower or thunderstorm will
still be possible during peak heating. Highs will be found solidly
in the 70s to low 80s in spots.

&&

.SHORT TERM /MONDAY NIGHT THROUGH THURSDAY/...
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Ridging aloft will remain in place through Tuesday night keeping
mainly dry conditions intact, before a cold front slowly crosses the
region bringing showers and thunderstorms to western and
northcentral NY midweek. Meanwhile, surface high pressure will move
from eastern NY to the New England coast by Tuesday night allowing
for very warm and increasingly humid conditions through Wednesday,
before cooler weather starts to filter in across the region Thursday
in wake of a cold front.

Mainly dry weather is expected Monday night through most of Tuesday
night with high pressure surface and aloft in control of our
weather. Other than limited diurnal instability developing second
half of Tuesday possibly producing an isolated shower or
thunderstorm during the afternoon/early evening hours along and
inland of any lake breeze circulations, ridging will suppress most
if not all convection. Very warm Tuesday with highs averaging about
10 degrees above average, translating to low to mid 80s for much of
the area, slightly cooler highest terrain areas. Tolerable humidity
levels will hold on for one more day.

Mid/upper level ridge starts to break down and shift east late
Tuesday night and Wednesday as upstream deepening trough digs
southeastward across the upper and central Great Lakes. At the
surface, several boundaries extending from associated low pressure
over northwestern Ontario will cross the area from late Tuesday
night through Thursday. First will be a weak warm front that may
spark off a few showers/isolated storm east of the Finger Lakes late
Tuesday night/early Wednesday at moves through. Next up will be a
prefrontal trough Wednesday, although overall forcing appears to be
fairly weak with this feature. That said, a very moist airmass in
place behind the warm front combined with strong diurnal heating may
produce some scattered showers and thunderstorms, especially during
the afternoon and evening. Muggy and warm conditions continue
Wednesday, with similar temperatures to Tuesday, however temps will
be lower in areas that see more persistent showers and storms.

The main show this time around will be with the actual cold front as
it slowly moves east across the area Wednesday night through the
first half of Thursday. Severe weather threat with the cold front
looks low at this time, especially with the poor diurnal timing. The
more notable threat looks to be heavy rain with any stronger
thunderstorms (tall skinny CAPE profiles) owed to a slow moving
front combined with PWATs upwards of 1.50-1.75 inches. In fact, WPC
has our area outlined in a MRGL Risk (5%) for heavy rain during this
timeframe. Cold front should clear east of the area by Thursday
afternoon, however a cool/moist cyclonic flow aloft associated with
a "bowling ball" trailing upper level low combined with an
increasingly unstable environment owed to strong diurnal heating
will keep the likelihood for showers and storms going through the
peak heating hours of the day. The deeper moisture will have been
stripped away with the earlier cold frontal passage, significantly
lowering the overall heavy rainfall threat. Stronger steering flow
aloft will also keep storms moving right along, although steepening
low level lapse rates and better shear profiles may allow a few
stronger storms to develop. Change back to a cooler regime
starts Thursday, with highs mainly in the 70s.
-- End Changed Discussion --

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
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Low forecast confidence for the Thursday night through Sunday
timeframe due to an upper level cut off low overhead of the Great
Lakes. Said upper level low will also allow a few embedded
shortwaves to round its base. This far our its hard to pinpoint the
exact location and timing of the shortwaves. Overall this will
support a persistent risk of showers and isolated thunderstorms each
day. Additionally, if the timing of the shortwave passages align
with peak diurnal heating there may be a threat that some
thunderstorms become frisky and turn severe. However on the
optimistic side of things there will be plenty of rain-free time
between shortwave passages.

With the upper level low overhead, expect a cooling trend as
continental polar air over Canada filters southeast across the Great
Lakes. Highs Friday through Sunday will range in the mid to upper
60s across the higher terrain and the low 70s elsewhere.
-- End Changed Discussion --

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A weakening low pressure system will bring some showers to
western terminals this afternoon. Otherwise...VFR expected to
continue for most terminals...the lone exception will be at KJHW
where periodic IFR Cigs will be possible.

Showers will weaken and diminish this evening. Lingering low-level
moisture and light wind flow will allow for areas of fog and
lowering Cigs areawide tonight. LIFR is likely for the hilltops of
the Southern Tier (KJHW), with IFR or low end MVFR expected for
KBUF/KIAG/KROC overnight.

Less moisture east of Lake Ontario may leave KART and surrounding
area VFR through much of the night.

Outlook...

Monday and Tuesday...VFR.
Wednesday...Mainly VFR with a chance for showers.
Thursday and Friday...VFR/MVFR with showers and thunderstorms.

&&

.MARINE...
Low pressure will bring some showers today but winds will remain
light with minimal wave action.

A weak pressure gradient will continue to maintain light winds and
minimal waves into mid-week.

&&

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

&&

$$

SYNOPSIS...AR
NEAR TERM...AR
SHORT TERM...JM
LONG TERM...EAJ
AVIATION...AR
MARINE...AR