Tonawanda Town, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

059
FXUS61 KBUF 230818
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
318 AM EST Sat Nov 23 2024

.SYNOPSIS...
A large area of low pressure off the New England coast will move
northeast today. Chances for rain and some nocturnal elevation wet
snow will continue through early Sunday before drier weather builds
in by Sunday evening. The next widespread chances for rain then
arrive by Monday night, with a colder airmass and chances for
showers downwind of the lakes following a cold front on Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
A dynamic low pressure system centered off the Long Island coast
early this morning will wobble northeastward and become vertically
stacked over the Canadian Maritimes today, remaining anchored over
the region through tonight. Moist cyclonic flow around this system
will maintain on and off chances for precipitation, while a thinning
ribbon of moisture to the west being pulled eastward increases these
chances over the course of the day.

Shower activity early this morning remains scattered, driven largely
by lake instability and upslope enhancements. Temperatures are still
cold enough across the in the low 30s across the higher terrain
areas to support a few wet flakes, though any additional
accumulations through daybreak are expected to be minimal. Following
sunrise, temps slowly warming into the 40s across the area will
favor rain as the dominant ptype even across the hilltops.

An elongated mid-level shortwave will slide southeastward out of
Ontario Province and pass north of the lakes this evening and
overnight tonight. This will bring with it a reinforcing shot of
colder air (850H temps -5C to -6C), though with a notable lack of
mid-level moisture noted on BUFKIT soundings not expecting an overly
robust lake response. This said, still expecting lake effect showers
with some drizzle in the mix to expand across much of the western
Southern Tier by this evening, while southeast of Lake Ontario a
weak upstream connection to Georgian Bay should result in a more
well defined and persistent band of rain. Boundary layer temps
tonight will be very marginal in supporting wet snow mixing in
across the hilltops of the Southern Tier, though the Tug
Hill/Western Dacks stand a better chance of picking up some
additional nuisance accumulations by Sunday morning.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A cool northwest flow regime will continue to support a period of
lake/upslope precipitation Sunday morning, behind the departed mid-
level low. Drier air working in at the mid-levels will bring a
diminishing trend to the precipitation by afternoon. Plenty of cloud
cover will remain through the day with high temperatures in the 40s.

Sunday night continues to look dry as weak high pressure settles
across the area.

High pressure will shift east of the area Monday. A southerly flow
of milder air ahead of an approach low pressure system will help get
temperatures into the upper 40s to lower 50s. The area of low
pressure will move through the Great Lakes Monday afternoon and
Monday night bringing a widespread rain ahead of an associated cold
front.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Next upper level trough will dive southeast across the Great Lakes
Tuesday, supporting a deepening Colorado low to advance northeast
across the central/lower Great Lakes. Overall this will support a
pair of fronts to cross the area, supporting daytime rain and a mix
of rain and snow at night. Should note that, breezy to blustery
conditions will be possible with this low pressure system, but it
will highly depend on the track of the surface low. If the low
tracks northeast across the central Great Lakes, expect a windier
forecast. As of right now, model consensus has the low tracking
overhead and kept windy conditions at bay for now.

By Tuesday night the trough will have deepened into an upper level
low, where the low will then lift northeast across New England into
the Canadian maritimes by Thursday, and place zonal flow across the
area. Overall a surface low pressure will slide northeast into New
England while surface high pressure pushes into the area in its
wake. A weak shortwave will pivot the exiting upper level low
helping provide some moisture and advect colder air (temperatures
drop to -6C at 850mb) in northwest flow. This will result in lake
effect precipitation southeast of both lakes. Temperatures will
drastically cool to support snow Tuesday night through Wednesday.
Surface high pressure will push east across New York State Thursday
supporting a dry start for the Thanksgiving holiday.

The next upper level trough will dive southeast across much of the
CONUS Thursday night and linger across the Great Lakes and New
England for the end of the week and into the next week. This will be
the first shot of lasting cold air this season. The next surface low
will be advancing east/east-northeast across southeast brushing the
southern portions of New York State, producing some rain and snow
showers. This low will then lift northeast along the Atlantic
coastline returning chances for some lake effect showers
southeast of the lakes Friday.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
Low pressure will continue to spin across the Northeast US
overnight. Scattered shower activity will persist though expect
coverage to decrease through the pre-dawn hours. Some wet snow
may continue to mix in across the high terrain at times. VSBYs
will improve to mainly VFR overnight. Widespread MVFR CIGS will
continue, with areas of IFR mainly across higher terrain.

Saturday, it will be mainly dry early with nothing more than a few
spotty, light rain/wet snow showers. A mid level trough will then
cross the area in the afternoon and combine with some lake
instability to bring increasing coverage of showers advancing from
west to east across the area. This will be mainly rain as
temperatures warm, with spotty MVFR VSBY in the steadier showers.
Fairly widespread MVFR CIGS will continue through the day, with some
higher elevation IFR.

Outlook...

Saturday night...VFR/MVFR with rain or wet snow showers across
higher terrain.

Sunday...VFR/MVFR with a chance of a rain or snow shower.

Monday...VFR/MVFR with a chance of rain during the afternoon and
evening.

Tuesday...MVFR with rain and snow showers likely.

Wednesday...VFR/MVFR with a chance of rain or snow showers.

&&

.MARINE...
A large low pressure system off the New England coast will move
northeast to the Canadian Maritimes today, then slowly weaken and
drift east into the Atlantic Monday. As the system moves and
tightens the pressure gradient over the lakes, north to
northwesterly winds will turn more WNW and strengthen today. Winds
and waves are then expected to remain elevated through Sunday.

In anticipation of these strengthening winds, have extended the
SCAs for the southern Lake Ontario shoreline through Sunday this
update. SCAs for Lake Erie and the eastern end of Lake Ontario
have also been added. Occasional gale force gusts are possible
this evening and overnight tonight, mainly over the southeastern
portion of Lake Ontario.

A ridge of high pressure will then bring subsiding winds and waves
across the lakes Sunday night through early Monday night.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory from 10 AM this morning to 4 PM EST
         Sunday for LEZ040-041.
         Small Craft Advisory until 7 PM EST Sunday for
         LOZ042>044.
         Small Craft Advisory from 1 PM this afternoon to 7 PM EST
         Sunday for LOZ045.

&&

$$

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