Union, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

870
FXUS61 KBGM 180835
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
335 AM EST Sat Jan 18 2025

.SYNOPSIS...
Partly to mostly cloudy and not as cold tonight. A gusty breeze
will develop around the Finger Lakes region. The dry conditions
will be brief as the next storm system brings a mix of rain and
snow to the area Saturday. A chance of snow Sunday will be
followed by very cold Arctic air that settles in through the
first half of next week.

&&

.NEAR TERM /THROUGH SUNDAY/...
1000 PM Update..

Southerly winds are increasing and an area of mid level clouds
is streaming into CNY at this time. Bumped overnight lows up a
few degrees, especially in the Syracuse metro area, where
temperatures are currently rising through the mid-30s. Touched
up PoPs, weather type, QPF and snow amounts for Saturday; but
overall the latest data was still on track with the forecast,
and any snow amounts will be low and slushy during the day
Saturday, as highs reach well into the 30s areawide.

00z guidance is starting to come in for the Sunday/Sunday night
system. The 00z HRRR continues with a more westward track,
spreading steady snow back well west/NW of Binghamton. The 21z
RAP is also in-line with, if not even further NW than the 00z
HRRR. The 00z NAM remains further south and east with the low
and steady snow area (compared to the HRRR and RAP). Still
awaiting the 00z CMC-regional, GFS, ECMWF and other guidance.

640 PM Update...

Low stratus is clearing out with the strengthening SW flow this
evening. With winds increasing through the boundary layer the
temperatures should hold pretty steady or slightly increase
across higher elevations despite the clear skies with the warm
air advection.

350 PM Update...

Dry conditions will be in place across the area tonight with
weak high pressure building in at the surface and ridging aloft.
Clouds continue to linger around the area, but are expected to
give way to some clearing this evening before thickening back up
again prior to daybreak tomorrow. Southwesterly winds are
expected to increase tonight with wind gusts of 25 to 30 mph
possible, especially around the Finger Lakes region and higher
terrain south of the I-90 corridor. With SW flow in place it
won`t be quite as cold tonight with low temperatures in the low
and mid 20s for most. Areas immediately around Finger Lakes
will be in the upper 20s to near 30 degrees.

The break from precipitation will be brief as high pressure
slides off to the east early tomorrow morning giving way to a
shortwave trough and surface cold front. Showers, mainly in the
form of snow initially push into the area from the south and
west during the mid to late morning hours, then transition to
elevation dependent rain and snow through the remainder of the
day. Model guidance and the high res CAMS do support there being
a dry slot developing across portions of NE PA and the
Catskills during the afternoon, so PoPs generally top out around
50% in this area tomorrow vs. likely (>60%) elsewhere. The
mixed precipitation is expected to change back over to all snow
showers tomorrow evening before tapering off. Snowfall amounts
tomorrow through tomorrow night are expected to be light on the
order of a coating to around an inch, with the exception being
northern Oneida County where two to three inches is possible as
precipitation looks to stay mainly in the form of snow combined
with a little lake enhancement during the afternoon. High
temperatures are expected to be in the low to mid 30s with upper
30s in some valley locations.

Winds shift back around to the northwest tomorrow night and it
will turn colder again with lows mainly in the teens. The
southern Catskills and portions of NE PA drop back into the
lower 20s.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
330 AM Update...

The Sunday winter storm will linger into the overnight hours as it
slides east. Another half inch to 2 inches of snowfall accumulation
will be possible east of I-81 during the first half of Sunday
night. Behind the departing system, cold, west-northwest flow
will kick off some lake effect snow showers. T850 temps will be
as low as -20 deg C. There is some uncertainty on how quickly
the storm system moves out and then how quickly the lake effect
snow develops. There is potential for a couple of inches in the
Finger Lakes region Sunday night if snow showers develop earlier
than expected. Currently the forecast has less than an inch for
this region. The 510 line (1000-500 mb thickness) drops south
of the region, indicating the arrival of an arctic air mass.
Lows will be in the single digits, though breezy winds will push
wind chills below zero.

Lake effect snow will continue through Monday night. During the
daytime, flow will favor snow over portions of CNY, though it is
uncertain exactly how the bands will set up. Most models show an
initial band that will be a combination of a Lake Erie and Lake
Ontario band. As the day progresses, some models show two separate
bands, one for each lake while others hang onto one band until the
overnight hours. Eventually, flow will become more southwesterly and
the bands will drift north of the region, though the Lake Ontario
band will clip N. Oneida at times. Despite the uncertainties, the
daytime will be the best chance for accumulations with localized
amounts  up to 2 inches possible. Then lighter amounts are expected
as the band(s) drift northward.

Temperatures will continue to plummet on Monday. Highs will max out
in the teens, though the Wyoming Valley may just reach the 20s. With
winds picking up, wind chills will be in the single digits. Clear
skies will support good radiational cooling overnight, so hourly
temperatures were bumped down using an equal blend of NBM and NBM
tenth percentile guidance. The lows were then derived from those
changes. Blustery conditions are expected as wind chills will fall
to -15 to -25 Monday night into Tuesday morning. Cold weather hazards
will likely be needed, but given it is still a few days out, this
is highlighted in the HWO for now.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
330 AM Update...

The continuation of the cold conditions will be the main concern
during the long term period. Through Wednesday, temperatures will
struggle to climb out of the single digits during the daytime hours
while falling below zero both Tuesday and Wednesday night. Wind
chills will once again fall below -15 both nights, though slight
improvements will be seen Wednesday night into Thursday morning. The
510 line will finally move back north as the cold air begins to
retreat on Thursday. Highs will climb back into the 20s by the end
of the week though single digits will still be possible for some
during the overnight hours.

A nearly week-long lake effect event is in store for the long term
period though west to southwest flow will keep most of the snow
north of the region. Still, on and off snow showers will be possible
across far northern portions of the region. Meanwhile, high pressure
will keep two separate coastal systems just out of the region
Wednesday and Friday. However, shifts in these tracks will be
possible over time, so both will need to be monitored throughout the
week.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
A weak wave will move through the region later today and cause
the current VFR conditions to drop to MVFR after 15Z with some
light rain mixing with snow into the afternoon. There could be
periods when the precipitation intensifies for short periods of
time. During these 1-2 hour windows in the afternoon, vsbys
could drop to IFR or less. The rain/snow showers will slowly
taper off after 22Z and make way for the colder and drier air
expected to move in after 02Z. East/southeast winds this morning
will become more southerly later today and then veer more to the
northwest Saturday evening.

Still expecting a period of LLWS at most terminals through 12Z
this morning due to a modest low level jet.

Outlook...

Saturday night...Mostly light lingering snow showers with
minimal restrictions.

Sunday...Some snow and associated restrictions possible. The
most favorable location will be AVP due to a passing coastal
low.

Monday through Wednesday...Lake effect snow showers and
associated restrictions possible, especially for KSYR-KRME.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...Winter Storm Watch from Sunday morning through late Sunday
     night for PAZ039-040-043-044-047-048-072.
NY...Winter Storm Watch from Sunday morning through late Sunday
     night for NYZ057-062.

&&

$$

SYNOPSIS...DK/MDP
NEAR TERM...AJG/DK/MJM
SHORT TERM...BTL
LONG TERM...BTL
AVIATION...BJT