630
FXUS61 KBUF 150830
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
330 AM EST Fri Nov 15 2024

.SYNOPSIS...
Low pressure over Lake Erie will continue to weaken through the
morning today, but clouds and a spotty shower or two will persist
through much of the day for WNY. High pressure and a large ridge
will build into the region tonight through the weekend. Fair dry
weather for the weekend will give way to a passing cold front Sunday
night, bringing showers to the area Sunday night and Monday.

&&

.NEAR TERM /THROUGH SATURDAY/...
Currently, earlier showers associated with a weakening sfc low over
Lake Erie have mostly eroded, though a few spotty showers/sprinkles
remain. Cloud cover remains over cast for most of the area south of
Lake Ontario, with some thinning out of clouds east of the lake.

Today, a few spotty showers are possible for WNY, especially near the
NY/PA line near Lake Erie. A sfc low and inverted trough over Lake
Erie and WNY will continue to weaken through the morning. Afternoon
showers for areas southeast of Lake Erie will be supported by a
passing vorticity ribbing and the low level moisture and upsloping
with a north/northwest flow. Showers shouldn`t add to much, around a
hundredth or two south of Buffalo. Cloud cover will remain in place
for most of the day, especially south of Lake Ontario where
lingering low level moisture will be stuck under an inversion. This
will result in mostly cloudy skies for WNY through the day today.
Cloud cover will continue to thin out for areas east of Lake
Ontario, with slow thinning from northeast to southwest later in the
day, mainly east of Rochester. Wind will remain below 10 mph on
land, and below 15 mph near the lakes. High temperatures today will
be in the mid 40s to low 50s across the area.

Tonight, cloud cover will continue to slowly thin out from northeast
to southwest through the night, but mostly cloudy skies can be
expected through the night across WNY, especially southeast of Lake
Erie. The combination of lingering low level moisture, departing
ribbon of vorticity and a northwest flow causing upsloping will
result in clouds to linger the longest in southwestern NY. A few
isolated showers/sprinkle can`t be ruled out for areas south of
Buffalo. Temperatures tonight will be in the mid to upper 30s for
area south of Lake Ontario where more clouds are expected; east of
Lake Ontario, temperatures will dip down to the low to mid 20s with
less clouds expected in these areas. Temperatures may be warmer in
areas where clearing is expected, but may not occur as quickly; or
cooler where clouds may clear out quicker than expected.

Saturday, high pressure and a ridge building into the region
will bring fair dry weather to the forecast area. Temperatures
will be in the mid 40s to mid 50s from the higher terrain to
the lower elevations. Clouds will continue to slowly erode over
the western third of the area, while the eastern portions of
the forecast area will be mostly sunny to sunny for the bulk of
the day.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A broad mid level ridge and associated sfc high will drift across
the Lower Great Lakes Saturday night and Sunday. This will promise
to provide us with continued fair dry weather with temperatures
surging into the mid 50s for most areas Sunday afternoon.

A robust shortwave over the Upper Great Lakes Sunday evening will
then push a cold front through our forecast area during the course
of Sunday night. While this frontal passage should be able to
generate at least scattered rain showers...its quick progressive
nature will limit QPF to under a tenth of an inch.

Fair weather will then return to the region on Monday...as strong
cyclogenesis over the central plains will combine with a large
closed low over the St Lawrence valley to pinch off an amplifying
ridge to our west through Monday night.  While this will once again
guarantee fair dry weather across the western counties...there will
likely be some residual showers over the Eastern Lake Ontario region
for at least a part of Monday.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
The pattern will become much more active during this period...as a
series of strong shortwave will eventually carve out a full latitude
trough that will end up evolving into an anomalously deep closed low
in the vcnty of the Lower Great Lakes/Mid Atlantic region. Given the
complexity of this whole scenario...the various guidance packages
have been very inconsistent with the timing and placement of the sfc
features. This has led to a relatively low confidence forecast for
this period and beyond into the weekend before Thanksgiving week.

That being said...Tuesday should feature the `nicest`[ weather of
this period. A broad mid level ridge over the Lower Great Lakes with
its associated sfc high nosing south from James Bay will provide dry
weather for the bulk of our forecast area...although the onset of
warm advection could be enough to allow for a couple showers over
the far western counties. Even if this were to come to pass...the
bulk of the day in that area should still be rain free. There will
be a better chance for this though Tuesday night when the axis of
the ridge should drift immediately to our east.

By Wednesday...several lobes of strong mid level energy are forecast
to develop a deep closed low over the mid western states. This is
where the confidence in the sfc features goes awry...as cyclogenesis
could take place anywhere from the Ohio valley to the Upper Great
Lakes. In either case...weak advection and a divergent upper level
flow over our region should be able to support at least a couple
nuisance rain showers with the bulk of the time being rain free.
Meanwhile...temperatures will remain above normal with highs
generally in the lower 50s.

On Thursday...guidance seems to be somewhat unified in depicting a
stacked storm system in the vcnty of Lake Erie or over our western
counties. This solution would likely bring a dose of moderately
heavy rain to our region...which is something that most areas could
certainly use.

&&

.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
Low level moisture associated with a weakening area of low pressure
over Lake Erie and a trough over the region, will continue to
provide low clouds across much of the area, especially south of Lake
Ontario. CIGs this morning to MVFR and even LIFR for KJHW will
continue over the next few hours. Patchy fog/mist over the higher
terrain is causing lower VSBYs over the higher terrain, including
KJHW, mainly down to MVFR, with periods of IFR.

Guidance is starting to come into better agreement that lower clouds
will linger longer into the day today, and even into tonight as low
level moisture remains in place longer. The best chance for lower
clouds will be south of Lake Ontario, where MVFR conditions are
expected for much of the day. Higher terrain areas, including
in/near KJHW will remain around the IFR/MVFR levels for CIGs today.

Tonight, lingering low level clouds will cause MVFR CIGs for most
areas south of Lake Ontario, with slow improvements through the
night from northeast to southwest to VFR conditions. Periods of IFR
CIGs will be possible at KJHW tonight.

Outlook...

Saturday and Sunday...VFR.
Monday...Restrictions possible with a chance of rain showers
east of the lakes.
Tuesday...VFR.

&&

.MARINE...
A weakening area of low pressure over Lake Erie and a trough over
the region brought earlier showers to portions of the lakes that
have mostly ended this morning. A few additional showers/sprinkles
will be possible over Lake Erie through tonight. The most notable
feature will be the lingering low clouds over the western marine
zones as low level moisture lingers through the day under an
inversion. Winds will back from the southeast to the northwest
through the day today, remaining at or below 10 knots for most areas.

Wind will continue out of the northwest through Saturday, with some
brief backing to the west on Saturday afternoon. Winds will increase
slowly tonight into Saturday nearing SCA levels for the southeast
portion of Lake Ontario. Winds will increase as a pressure gradient
develops over the lakes with an area of high pressure moving into
the region with a sfc low over the Canadian Maritimes.

Winds will weaken through Saturday night and remain below SCA
through the day on Sunday. Winds will pickup some later Sunday, with
choppy conditions expected on Lake Erie. Winds will back from the
northwest to the south and southwest Saturday night into Sunday.

&&

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

&&

$$

SYNOPSIS...SW
NEAR TERM...SW
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...SW
MARINE...SW