Hamburg, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

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FXUS61 KBUF 221205
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
705 AM EST Sun Dec 22 2024

.SYNOPSIS...
Lingering nuisance light lake effect snow showers south of the lakes
will gradually taper off through the day as the center of Arctic
high pressure moves directly overhead this afternoon. Plenty of
clouds around this morning, and although clouds will be stubborn to
break up, some peaks of sun will be possible as the afternoon wears
on. One more very cold day before a pronounced warming trend and dry
weather to start the new work week. A weak low pressure system will
then bring a period of mainly light snow Monday night into Tuesday,
with a mainly dry and seasonable day expected on Christmas.

&&

.NEAR TERM /THROUGH TONIGHT/...
A cold northerly flow continues across the area this morning to the
east of an approaching Arctic high. This will allow lingering light
lake effect snow showers to continue for most areas south of both
lakes through at least the morning hours, although coverage will
gradually shrink through the day. Only very minor additional
accumulations expected. Aforementioned Arctic high will move
directly overhead, finally putting an end to any lingering nuisance
lake snow showers through the afternoon with dry weather for most
areas, however any sunshine will likely be limited with low level
moisture trapped beneath a stout inversion just off the deck. Best
chances for any sun will be later in the day. One more very cold day
on tap. In fact, daytime highs will be the coldest so far this
season with single digits across the North Country and teens
elsewhere. Much lighter winds today will at least help temper some
of the bite to the very cold airmass.

Dry weather will continue tonight as center of Arctic high pressure
slowly drifts from eastern NY into western New England. Clear skies
and light winds initially will allow temperatures to quickly plummet
through the first half of tonight, especially east of Lake Ontario.
However, as the high slides further east later tonight, weak
southerly flow will take hold likely stopping temperatures from
dropping a lot more second half of the night. Of note, if the
position of the high remained overhead tonight, it would be much
colder than the already very chilly low temperatures we will
experience. In fact, after lows quickly dip down below zero across
the North Country and single digits elsewhere, temperatures may
actually start to slowly rise late tonight as WAA starts to get
underway.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
After a very cold weekend...temperatures during this period will
rebound to just above near normal late December values. This
moderation in temperatures will come as a result of a deep longwave
trough in the East that will be replaced by a low amplitude
progressive pattern...one that push a relatively weak storm system
through our region. While the impacts from this next system will be
minimal...it should generate enough snow to nearly guarantee a white
Christmas for the bulk of the region. Lets get into the details.

An area of Arctic high pressure will ease off the East coast on
Monday...while a vigorous shortwave will push a weak sfc low across
the Upper Great Lakes. Fairly strong warm advection between these
features will focus its associated isentropic lift on areas from
Lake Ontario northward...but there should be enough forcing
elsewhere to support some light snow...which could be mixed with a
bit of light rain near Lake Erie and even over the Southern Tier. In
any case...snow accums will be negligible with most areas only
picking up a coating to at most a half. NO TRAVEL PROBLEMS are
expected as the mercury will climb into the low to mid 30s over the
western counties and to between 25 and 30 east of Lake Ontario.

The strong shortwave...defined as per the 1.5 PV sfc being folded to
as low as 500-600mb...and its associated weak sfc low will cross the
Lower Great Lakes Monday night. Deep forcing from its passage will
support widespread snowfall that will accumulate to an inch or two
over the western counties and to as much as 2-4 inches east of Lake
Ontario. While there could be a relatively short burst of snow that
could quickly cover area roadways...snowfall rates that will average
under an inch will combine with min temps of 25-30 in the west and
close to 20 east of Lake Ontario to allow for easier maintenance of
area roadways. Travel problems should be minimal.

As the quick moving shortwave exits across New England on Tuesday...
high pressure centered over Quebec will arch back across all of the
Great Lakes region. With the forcing removed and all of the mid
level stripped away...residual light snow early Tuesday morning will
give way to nuisance lake enhanced/upslope snow showers that will be
focused over the Finger Lakes region. Additional snowfall on Tuesday
will be under a half inch in most areas. Unfortunately...the upslope
flow will maintain a wealth of strato-cu...especially south of Lake
Ontario.

Christmas eve and Christmas Day will feature dry...uneventful
weather as the area of Canadian high pressure will remain extended
across our forecast area. NO WEATHER TRAVEL ISSUES ARE EXPECTED.

Confidence in the forecast drops off Christmas night though...as
some of the mainstream deterministic models are suggesting that some
light snow could move on the backside of the aforementioned sfc high
and ahead of an approaching shortwave. Meanwhile...ensemble guidance
is leaning towards continued fair weather.

&&

.LONG TERM /THURSDAY THROUGH SATURDAY/...
While a low amplitude pattern will be in place across the country
during this period...ridging will be favored over the Great Lakes
and Ohio valley. This will result in a HIGH CONFIDENCE forecast of
temperatures that will average WELL above normal...particularly by
the end of the week when the mercury will climb into the 40s. These
readings will average some 10 to 15 degrees above typical late
December values.

The bulk of this forecast period will be pcpn free. There is low
confidence that Thursday will be dry and uneventful...but there are
a few deterministic packages that suggest that a nuisance light
rain/snow event cannot be ruled out.

Otherwise...our next real chance for pcpn will come during the
weekend when a southern stream storm system could spread some rain
over the area.

Looking further out...there is strong consensus within the guidance
community that general ridging will remain in place over the eastern
third of the country right up to New Years Day. This will combine
with a prolonged flow of Pacific based air over the nation to nearly
guarantee that our temperatures will average above to much above
normal between Christmas weekend and New Years.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A cold northerly flow will continue to produce lake clouds and light
lake effect snow showers south of the lakes through at least this
morning. Expect mainly low VFR/MVFR CIGS and VFR VSBY in very light
snow showers for terminals south of both lakes through this morning,
although some brief periods of localized MVFR/IFR VSBYs will be
possible in areas of more persistent snow showers (KROC/KIAG/KJHW).
Shallow low level moisture trapped under a stout low level inversion
has advected south into KART from the Saint Lawrence Valley, thus
high-end MVFR CIGS will likely continue through at least this
morning there.

Light nuisance lake effect snow showers will finally taper off as
they retract over Lake Ontario through the afternoon with high
pressure building in, however clouds will be tough to erode as low
level moisture remains trapped under a strong low level inversion.
Low VFR/MVFR CIGS may linger into at least a portion of the
afternoon before more pronounced scattering out of the low level
cloud decks by late in the day.

Widespread VFR flight conditions are then expected tonight with high
pressure over the area.

Outlook...

Monday...VFR.

Tuesday...Restrictions possible with rain/snow showers likely.

WEDNESDAY and THURSDAY...VFR.

&&

.MARINE...
Arctic high pressure building in across the lower Great Lakes from
the north has allowed pressure gradient to gradually relax, thus
winds have decreased enough that the remaining SCAs on Lake Ontario
have been allowed to expire. Winds and waves will continue to lessen
through the morning hours, with light chop at worst found across
southeastern Lake Ontario by this afternoon, lasting through
tonight.

Winds turn southerly and will slowly increase late tonight through
the day Monday, although the offshore component to the winds will
keep the higher building waves in Canadian waters through Monday
afternoon. A brief period of near SCA conditions will be possible on
both lakes Monday night as a weak area of low pressure crosses the
lower Great Lakes, especially Lake Erie where winds veer more
southwesterly bringing more of an onshore flow. Conditions are then
expected to remain below headline criteria through the remainder of
the work week.

&&

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

&&

$$

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