ZCZC SPCSWOMCD ALL
ACUS11 KWNS 170254 
SPC MCD 170254 
NYZ000-170730-

Mesoscale Discussion 0077
NWS Storm Prediction Center Norman OK
0854 PM CST Tue Jan 16 2024

Areas affected...Downstream of Lakes Ontario and Erie

Concerning...Heavy snow 

Valid 170254Z - 170730Z

SUMMARY...An intense lake effect snow band off of Lake Ontario will
persist through the overnight hours, with rates up to 2 in/hr. An
additional lake effect band may intensify off of Lake Erie through
the early morning hours.

DISCUSSION...On the backside of a departing midlevel shortwave
trough lifting northeastward across the Northeast, low/midlevel flow
has become favorably aligned with the long axis of Lake Ontario,
where an intense lake effect snow band has developed. Latest radar
data and web cams suggest rates up to 2 in/hr over Oswego County
with this organized band. Over the next few hours, low-level flow
should remain unidirectional and maintain a favorable direction for
the persistence of this band, with the heaviest snowfall rates
expected over Oswego County. Rates up to 2 in/hr will be aided by
persistent surface confluence along the lake and a modestly deep
convective boundary layer extending up to about 2 km. In the 04-06Z
time frame, low-level flow will back to a west-southwesterly
direction, likely shifting the lake effect band northward into
Jefferson County with time. However, increasing subsidence on the
backside of the aforementioned midlevel trough could lead to
decreased convective boundary layer depths and a slight reduction in
rates.

Off of Lake Erie, latest radar data shows some intensification of a
lake effect snow band extending into Erie County. While low-level
flow is modestly aligned with the long axis of the lake, the backing
low-level winds with time should yield a more persistent band into
the early morning hours. Thermodynamic conditions appear slightly
less conducive compared to Lake Ontario, though rates could approach
2 in/hr if the snow band becomes persistent and organized.

..Weinman.. 01/17/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...BGM...BUF...

LAT...LON   43287614 43427682 43567703 43747686 43877642 43877607
            43847576 43747538 43527526 43207551 43287614 

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