693
FXUS61 KBUF 192050
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
450 PM EDT Sat Oct 19 2024

.SYNOPSIS...
Strong high pressure will remain centered from the Ohio Valley to
the Mid Atlantic through the first half of the upcoming week,
allowing the stretch of fine dry weather to continue through
Tuesday. Temperatures will continue to warm, peaking at values well
above average early next week. A strong cold front is expected to
cross the eastern Great Lakes late Wednesday with a chance of
showers, followed by much cooler temperatures for a few days late
next week.

&&

.NEAR TERM /THROUGH SUNDAY/...
Clear moonlit skies and light winds tonight will once again support
strong radiational cooling. The ongoing gradual warming trend will
keep lows in the upper 30s to lower 40s on the lake plains, with low
to mid 30s in the typically cooler Southern Tier Valleys and North
Country. There will be some patchy frost again in those colder
areas, but coverage will be less than the past few nights and the
majority of the frost will be in counties where the frost/freeze
program is no longer active. With this in mind, no Frost Advisories
are necessary for tonight.

Expect some areas of fog to develop again overnight through Sunday
morning, likely in similar areas to the past few nights. Fog will be
most likely across the Southern Tier river valleys, and also north
of other water bodies such as the Finger Lakes and Niagara River
where weak southerly flow off the water will add some moisture to
the near surface environment.

Sunday, the fog will burn off by mid to late morning. Otherwise,
sunshine will continue with just some high/thin cirrus later in the
day as a mid level shortwave passes by to the north of the area.
Temperatures will add a few degrees over today, with highs in the
low 70s for lower elevations and mid to upper 60s for higher
terrain. There will be a little more wind than recent days, with
southwest winds gusting in the 20-30 mph range northeast of the
lakes by afternoon.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
Fair, dry, and warmer weather to close out the weekend will last
through early next week as a large expanse of surface high pressure
initially ridging along the spine of the Appalachians builds
northeast off the New England coast. A tightening pressure gradient
between this area of high pressure and a shortwave far to the north
across Quebec will bring some breezy SW winds across the Lakes
through Monday, especially northeast of Lake Erie where gusts to
30mph are possible in the afternoon.

Otherwise, 850H temps within this airmass are expected to hover
around +14C for much of this period, which will translate to daytime
highs well into the 70s in many areas, some low 80s not out of the
question across the typical warm spots in the Genesee Valley and
Finger Lakes. Temps will likely be a few degrees cooler immediately
northeast of the lakes owed to the onshore flow (lake temps in the
low 60s). Overnight lows Sunday and Monday nights will range from
the 40s across the higher terrain east of the lakes to the low/mid
50s across the Lake Plains. Tuesday night will be even warmer, with
widespread 50s for lows.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The longwave closed low and associated trough in the southern
southern branch of the jet stream will lie across the Pacific
southwest of the CONUS this weekend. This trough will pull northeast
and into the upper Great Lakes by Tuesday and then cross the Great
Lakes Wednesday as the next northern stream trough dives southeast
across central Canada towards the Great Lakes. Overall this troughy
pattern will support active weather to close out the second half of
the week.

Getting into the specifics, a cold front will sweep across the
region from northwest to southeast Wednesday afternoon and night. In
the wake of the frontal passage and the cold air (~ -3C at 850 mb)
filtering across the region due to the trough overhead, lake effect
rain showers will continue southeast of the lakes Thursday with a
few snowflakes possible across the higher terrain of the eastern
Lake Ontario region Thursday night.

With the aforementioned trough exiting the Northeast Thursday night
through Saturday, surface high pressure will extend east into the
lower Great Lakes supporting dry weather to return.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
Wall to wall VFR will continue through this evening with clear
skies beneath strong high pressure.

Overnight, expect areas of fog to develop with local IFR/LIFR. With
little change in the pattern or airmass, expect fog to develop in
similar locations to last night, with fog most prevalent across the
Southern Tier river valleys and north of other bodies of water such
as the Finger Lakes and Niagara River as weak southerly over the
water flow adds some additional moisture to the near surface
environment.

Sunday, the fog will burn off by mid to late morning, leaving VFR to
prevail the rest of the day with nothing more than some high/thin
cirrus later in the day. There will be more wind than recent days,
with southwest gusts in the 20-25 knot range northeast of the lakes
by afternoon.

Outlook...

Sunday night through Tuesday night...VFR.
Wednesday through Wednesday night...VFR deteriorating to MVFR with
showers likely late Wednesday and Wednesday night.
Thursday...VFR/MVFR with a chance of showers, especially southeast
of Lake Ontario.

&&

.MARINE...
High pressure centered near the lower Great Lakes will gradually
drift south, becoming centered on the Ohio Valley and Mid Atlantic
by Sunday. Meanwhile, a front will pass by well north of the region
through Quebec Sunday. The pressure gradient will tighten somewhat
over the lower Great Lakes Sunday between the two systems, allowing
winds to increase into the 15-20 knot range. This will bring a
moderate chop to Lake Erie and Lake Ontario, with winds and waves
possibly approaching Small Craft Advisory criteria for a time Sunday
afternoon through Sunday night. Winds and waves will gradually
subside Monday through Tuesday.

&&

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

&&

$$

SYNOPSIS...Hitchcock
NEAR TERM...Hitchcock
SHORT TERM...PP
LONG TERM...EAJ
AVIATION...Hitchcock
MARINE...Hitchcock