Irondequoit, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

218
FXUS61 KBUF 050002
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
702 PM EST Thu Dec 4 2025

.SYNOPSIS...
The coldest airmass of the winter season arrives tonight leading to
Friday morning wind chills dropping near to below zero, especially
across north-central NY. Mainly dry weather will return by Friday as
high pressure briefly builds into the eastern Great Lakes ahead of
our next chance for snowfall Saturday.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
Northwest flow continues to support weak multi-band lake effect east
of the Lakes, however a weakening trend will continue through the
evening hours. Little to no additional accumulation is expected
tonight.

High pressure will build across the eastern Great Lakes region
tonight and move into the Northeast Friday resulting in mostly dry
weather. The next system with another round of snow for much of
western NY will begin to approach the region late Friday night.

The coldest airmass of the young winter slides overhead with
850mb temps dropping between 18 and 20 degC below zero. These
850mb temps will be near the lowest climatological percentile
for early December. With clearing skies in areas outside of
lingering lake effect bands and calming winds, Friday morning
low temperatures will drop into the single digits for most with
temperatures dropping to zero to 10 below across the North
Country.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Saturday and Saturday night low pressure will meander across
southern Hudson Bay...and in the process will slowly push its
trailing cold front eastward from the central Great Lakes and across
our region...with the front possibly being preceded by a weak
prefrontal trough during the day Saturday. Out ahead of these
features...a sheared south-southwesterly flow of just-marginally
cold enough air will allow weak lake effect snow showers to
initially develop north-northeast of the lakes during the first part
of Saturday morning...with the bands then shifting southward and
temporarily becoming a little better organized later Saturday
morning/Saturday afternoon in tandem with veering of the low-level
flow and a commensurate increase in fetch across the lakes...some
gradual cooling aloft...and a brief uptick in mid-level moisture.
This will not last long though...as by late Saturday/Saturday
evening our airmass will have dried back out aloft...with further
drying out of the low levels then expected through the balance of
Saturday night. With the low level flow further veering from
westerly to west-northwesterly during this latter time frame...this
will result in the lake effect snow showers weakening across the
traditional snow belts east and east-southeast of the lakes
Saturday night.

With respect to snowfall amounts...these continue to look to only be
in the light to modest range Saturday/Saturday night given both the
fairly mobile nature of the lake snows (which will cut down on
residence time) as well as the only marginally favorable environment
initially...the general lack of deeper moisture for much of the
time...and a decent amount of shear. In general expect accums to
range from 1-2" east of Lake Erie to to 1-3" east of Lake Ontario...
with the greatest amounts focused across the higher terrain in both
instances. Outside of these...the rest of the area should merely see
some scattered light snow showers or flurries with only some very
minor accumulations.

By Sunday morning only some very limited leftover snow showers/
flurries will be left southeast of the lakes...with these fading
away during the morning as the low-level flow becomes unfavorable
(east to southeast) out ahead of an advancing weak wave of low
pressure...whose existence the guidance suite has come into notably
better agreement on since yesterday at this time. The main guidance
packages all now suggest that this latter feature will then make its
way across or just south of our region later Sunday and Sunday night
while bringing a more general round of light to modest snowfall (1-
3"/2-4" in most places...with the higher terrain east of Lake
Ontario possibly seeing some marginally advisory-worthy (3-5")
amounts. As this system pulls east of our longitude later Sunday
night...its synoptic snow will then give way to some weak lingering
lake effect snow showers south of the lakes as a northerly flow of
much colder and drier air overspreads our region in its wake.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Northerly flow of much colder but dry air will keep scattered light
snow showers/flurries going south of the lakes (particularly Lake
Ontario) Monday morning...before building low level ridging shuts
these down from west to east Monday afternoon. Otherwise Monday will
feature our coldest daytime highs of the young winter season to
date...with maxes only expected to range from the upper teens across
the North Country and higher terrain south of Lake Ontario to the
lower 20s elsewhere.

After that...the low level ridge will then drift southeast and off
the mid-Atlantic coastline through midweek...while a pair of clipper-
type systems (the second stronger than the first) make their way
eastward/northeastward across the Great Lakes and southeastern
Canada/New England...with the guidance suite currently exhibiting a
decent amount of spread in the strength and track of these lows. In
general this should bring increasing chances for some light to
modest synoptically-driven snow showers to our region as we push
through midweek along with at least a modest warming trend...with
the latter also possibly allowing some rain to mix in by Wednesday.
Following the passage of the second low...much colder air then looks
poised to return by Thursday along with renewed chances for lake
effect snow showers downwind of the lakes.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
Northwest flow continues to support light multi-band lake effect
snow showers east/southeast of the Lakes this evening. A weakening
trend will continue with the last of the MVFR conditions becoming
VFR by midnight. As high pressure builds into the region, widespread
VFR conditions are expected through Friday.

Outlook...

Friday Night...Mainly VFR.

Saturday through Sunday...VFR/MVFR with a chance of snow showers.
Local IFR in lake effect snow showers east of the lakes.

Monday and Tuesday...VFR/MVFR with a chance of light snow
showers.

&&

.MARINE...
Northwest winds will gradually weaken tonight with Small Craft
Advisory conditions commencing tonight. Friday will be relatively
calmer before gusty southwest winds return with our next system on
Saturday.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 10 PM EST this evening for LEZ040-
         041.
         Small Craft Advisory until 10 PM EST this evening for
         LOZ042.
         Small Craft Advisory until 1 AM EST Friday for LOZ043>045.

&&

$$

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