814
FXUS61 KBUF 160218
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1018 PM EDT Sun Sep 15 2024

.SYNOPSIS...
High pressure will maintain the very warm, tranquil weather pattern
across the area through at least Tuesday. A low pressure system
moving inland from the Carolina coast to the Mid Atlantic will then
spread moisture northward towards the area Tuesday night through the
middle of the week. This will bring an increase in clouds and
possibly a few showers by midweek, although the better chance of
rain may stay south of our region.

&&

.NEAR TERM /THROUGH MONDAY/...
Lather, rinse, repeat. Dominant, blocking high pressure surface and
aloft over the Northeast US will essentially allow our weather to
repeat again tonight through Monday, with very similar conditions to
the past few days.

The diurnal cumulus have mostly dissipated, with clear skies across
the region late this evening. The clear skies and light winds
overnight will promote patchy fog east of Lake Ontario and across
the river valleys of the Southern Tier. Lows will drop back into the
upper 50s to lower 60s in most areas, with some low to mid 50s in
the typical cool spots of the Southern Tier and North Country.

Monday, another dry day as the ridge and high pressure over the
region slowly pushes east. Some high clouds will advance north into
the area later in the day out ahead of an approaching low pressure
system, and some diurnal cumulus will likely develop again inland
from the lakes. Highs will range from the low to mid 80s for the
lower elevations to the upper 70s for higher terrain. Local lake
breeze circulations will keep the lakeshores in the 70s.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
Deep-layer ridging still draped across our region Monday night will
withdraw southeastward into the western Atlantic through midweek.
Meanwhile a subtropical/tropical low near the Carolina coast Monday
evening will push inland and weaken Monday night and Tuesday...with
the remnant broad mid/upper level circulation from this feature then
continuing to push northwestward to the central Appalachians/Upper
Ohio Valley through the end of the period.

The slowly departing ridge will maintain fair dry weather across our
region through Monday night...with just a gradual south-to-north
increase in mid and high clouds anticipated well out ahead of the
aforementioned coastal system. Thereafter...increasing/deepening
southeasterly flow in between the advancing low and departing ridge
will advect increasing amounts of Atlantic moisture into our region
through midweek...bringing a general increase in cloud cover and
eventually some shower chances.

With nature yet to really show its hand with respect to how much
subtropical/tropical development of this system will occur before it
moves inland...the various guidance packages rather unsurprisingly
continue to struggle with its track/speed/strength...and
consequently the timing and placement of any associated showers.
With this in mind have continued to lean more heavily toward a mix
of continuity and blended guidance...and have just indicated a mix
of 20-40 PoPs spreading across the area from south to north Tuesday
afternoon through Wednesday for now.

As for temperatures...these will still remain above normal given
little to no change to our warmer-than-average airmass...though in
general daytime highs should trend a little downward through midweek
with the increasing cloud cover and shower potential...with these
primarily ranging through the 70s by Wednesday. Meanwhile the
increasing cloud cover will have the opposite effect on nightly
lows...with these moderating to the upper 50s and lower 60s for both
Tuesday and Wednesday nights.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
An upper level low over the Mid-Atlantic region will merge with a
trough over the Northeast region Thursday through Friday. An
anomalously strong ridge over the Mississippi Valley will move into
Ohio Valley and Great Lakes region, replacing the trough as it exits
to the east.

Moisture will be somewhat pooled under a weakening upper level low
across the Mid-Atlantic region into New York State Thursday. Surface
high pressure will be centered near the Upper Great Lakes and extend
into western and north central NY. Daytime heating and dewpoints in
the 60s may result in the development of showers and a few
thunderstorms Thursday afternoon through evening. Due to no obvious
lifting mechanisms nearby, coverage looks scattered. Subsidence
builds into the region Friday which will be mostly dry, however
isolated to scattered showers remain possible inland from the lakes.
A 585dm ridge will move into the region Saturday and Sunday, with
medium to high confidence of another warm and dry weekend.

Above normal temperatures will continue Wednesday through Saturday.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Diurnal cumulus have dissipated this evening, leaving mainly clear
skies overnight. Expect patchy fog with local IFR once again tonight
through Monday morning, mainly across the river valleys of the
Southern Tier and east of Lake Ontario. Most of the TAF sites will
stay VFR overnight. KJHW has not been impacted much by fog the past
few nights, and expect that trend to continue tonight. KART may see
some IFR from late evening through early Monday morning.

Monday, once the fog burns off, expect VFR to prevail the rest of
the day with some diurnal cumulus in the afternoon, and a modest
increase in high cirrus from south to north later in the day.

Outlook...

Tuesday...Mainly VFR.

Tuesday night and Wednesday...Mainly VFR. A small chance of showers.

Thursday and Friday...Mainly VFR.

&&

.MARINE...
High pressure will continue to dominate the weather pattern over the
eastern Great Lakes early this week, with light winds and minimal
wave action. Light synoptic scale winds will again allow local lake
breeze circulations to develop Monday afternoon with onshore winds
of 5-10 knots in most areas.

The pressure gradient will tighten a bit by Tuesday as a low
pressure system slowly drifts northward from the Mid-Atlantic
states. This will lead to a prevailing light to moderate east-
northeasterly breeze on the lakes, which could result in a minor
chop on the western end of Lake Ontario at times. This low pressure
system could also bring a few showers to the lakes around midweek.

&&

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

&&

$$

SYNOPSIS...Hitchcock/PP
NEAR TERM...Hitchcock/SW
SHORT TERM...JJR
LONG TERM...HSK
AVIATION...Hitchcock
MARINE...Hitchcock/PP