Area Forecast Discussion
Issued by NWS Buffalo, NY
FXUS61 KBUF 221853
Area Forecast Discussion
National Weather Service Buffalo NY
253 PM EDT Sat Oct 22 2016
Rain will linger across the Eastern Lake Ontario region through
tonight, mixing with and changing to snow across the higher
elevations of the Tug Hill Plateau. Things will dry out Sunday
before another disturbance brings a chance of showers Sunday
night. Otherwise, cool northwesterly flow will keep temperatures
below average into the middle of the week, with a chance of lake
effect rain showers southeast of the lakes.
.NEAR TERM /THROUGH SUNDAY/...
Rain will continue into tonight across the eastern Lake Ontario
region as the wrap-around moisture on the western flank of the
departing low pressure system continues to slide across the area.
As temperatures across inland portions of the North Country fall
well into the 30s, we will see the precipitation change over to snow
across the higher elevations of the area, with an accumulation of up
to three inches possible across the highest portions of the Tug Hill
and the Western Adirondacks overnight.
Elsewhere, expect plenty of lake-effect cloudiness to persist. Any
precipiation should be limited to patchy drizzle or maybe a flurry
across the higher terrain of the Southern Tier, as the bulk of the
moisture will be confined to the lowest 3000 ft of the atmosphere,
with a strong subsidence inversion above that level. Temperatures
will fall into the mid to upper 30s in the Southern Tier, with
lower 40s near the lakes, though a continued brisk west-northwest
flow will drop wind chill values into the 20s.
Cyclonic flow will continue to slowly depart the area Sunday with
much of the day expected to be dry. Lingering cold northwest flow
could bring some light precipitation southeast of the lakes early in
the day. Band of warm air advection develops into the region with an
increase in cloud cover during the afternoon. A solid improvement in
the temperature department, although still a bit below normal with
most highs Sunday in the lower 50s, expect 40s across the North
.SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
Sunday night...a fast moving shortwave will quickly slide from Lower
Michigan to Long Island...with an associated weak surface low passing
along or just south of the New York/Pennsylvania border. These two
features will bring a quick shot of scattered to numerous rain
showers to areas along and south of Interstate 90...with the most
numerous activity found across the Southern Tier where some likely
PoPs remain in play. Elsewhere...conditions should be cloudy and mainly
dry aside from some scattered/limited lake effect rain showers east-
southeast of Lake Ontario...with these tending to fade overnight as
some modest drying develops in the wake of the departing shortwave.
After that...our weather for the remainder of this period will be
dominated by persistent upper level troughing...the core of which
will only slowly drift from Quebec Province to the Canadian Maritimes.
This feature will feed a continued northwesterly to northerly flow of
colder Canadian air across our region...which will result in temps
averaging solidly below normal through midweek. More specifically...
expect daytime highs mostly in the upper 40s to lower 50s on Monday
to pull back into the lower to mid 40s for both Tuesday and Wednesday
as our airmass cools...while nighttime lows mostly ranging through the
30s Monday night will drop off into the upper 20s and lower 30s Tuesday
night...quite possibly resulting in a killing freeze in those areas
where the growing season has not yet ended.
Precipitation-wise...the continual northwesterly to northerly flow of
Canadian air will also result in a potential for some lake effect
precipitation southeast and south of the lakes. This stated...the
combination of the short fetch...a fairly low (4-5 kft) capping
inversion...and less than impressive moisture below this level should
all help to keep any such activity fairly limited/scattered in nature.
As such...have kept PoPs confined to the 20-40 range...with the highest
values indicated southeast of Lake Erie Monday night/early Tuesday...
where and when moisture will be a little bit more favorable. The
predominant ptype with this should be rain...except at night and early
each morning when the boundary layer should be cool enough to support a
little wet snow inland from the lakes and/or across the higher terrain.
Any lake effect activity that does form should then come to an end
during the day on Wednesday...when surface-based ridging settles
directly overhead along with increasing large-scale subsidence and
.LONG TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
High pressure initially draped from Western Quebec to Central New
York will slowly drift east into New England Wednesday night...while
developing low pressure tracks from the mid-Mississippi valley into
the Western Great Lakes. For most of our region...this should merely
result in dry weather persisting through the night along with clouds
increasing from west to east...though a few showers associated with
the approaching low may reach far Western New York late.
The forecast become very unclear for Thursday and Thursday night as
00z model guidance shows a large divergence of solutions between the
EC and GFS/CMC. The EC is an outlier tracking the Central Plains
surface low across the Great Lakes into southeast Ontario while the
GFS/CMC both show the low weakening/dissipating over the lower
Ohio/mid Mississippi river valleys. Due to this large spread in
forecast guidance have leaned heavily on the SuperBlend which
actually favors the EC solution. This puts chance POPs in play for
Thursday into Friday. Temperatures both Thursday and Friday should
top out in the low to mid 50s.
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
Cold air advection on northwesterly flow will continue to generate
MVFR cigs across the forecast area this afternoon, with IFR
conditions likely to persist across the higher terrain of the
Southern Tier and North Country. Expect gradual improvement across
Western New York after 21Z, as deeper low level moisture begins to
shift away to the east.
Lingering rain showers may change over to snow showers later
tonight across the higher elevations of the Tug Hill Plateau and
Sunday...MVFR/VFR. A chance for rain showers SE of the lakes.
Wednesday and Thursday...VFR.
Surface low pressure will deepen as it moves north across Maine
and into Quebec through tonight. The tightening gradient between
this low and a narrow ridge of high pressure moving into the
central Great Lakes coupled with increasing cold air advection
will allow northwesterly winds to freshen to gale force tonight
across central Lake Ontario, and appropriate warnings remain in
effect. Elsewhere, the brisk northwesterly flow will keep small
craft advisories in play well into Tuesday before high pressure
moves overhead Tuesday night into Wednesday.
MARINE...Small Craft Advisory until 2 AM EDT Monday for LEZ041.
Small Craft Advisory until 3 PM EDT Sunday for LEZ040.
Small Craft Advisory until 8 PM EDT this evening for
Gale Warning from 10 PM this evening to 11 AM EDT Sunday
Small Craft Advisory until 2 AM EDT Sunday for LOZ043-044.
Gale Warning from 2 AM to 11 AM EDT Sunday for LOZ043-044.
Small Craft Advisory until 11 PM EDT Sunday for LOZ042-045.
Small Craft Advisory until 7 PM EDT Sunday for SLZ022-