SPC MD 62

[NorthGeorgiaWX]

MD 0062 CONCERNING SNOW SQUALL FOR PA INTO SOUTHERN NY

Mesoscale Discussion 0062
NWS Storm Prediction Center Norman OK
0725 AM CST Sun Jan 14 2024

Areas affected...PA into southern NY

Concerning...Snow Squall 

Valid 141325Z - 141700Z

SUMMARY...Snow squall potential will spread east-northeastward this
morning across Pennsylvania into parts of southern New York. The
stronger squalls will be accompanied by brief heavy snow rates,
gusty winds, and abrupt visibility reductions.

DISCUSSION...Multiple snow bands are ongoing across parts of
western/central PA this morning. These bands are ongoing within a
broadly confluent frontal zone and are likely being aided by a
mid/upper-level shortwave trough approaching the upper Great Lakes
region. The downstream environment is expected to become
increasingly favorable for snow squalls with time, with strong
cooling aloft (dropping below -20C at 700 mb) supporting steep
low-level lapse rates and SBCAPE eventually approaching 100 J/kg,
even with temperatures only warming into the low 30s F. The ongoing
snow bands have already produced gusts in the 30-35 mph range, and
strong southwesterly flow in the lowest 3 km AGL may support gusts
greater than 40 mph, as low-level lapse rates steepen with time.   

It remains uncertain as to whether a more organized and extensive
snow band will develop with time, with frontal convergence expected
to remain relatively modest. However, even if such a band does not
evolve, multiple smaller-scale bands will be capable of producing
snow squalls with briefly heavy snow rates, gusty winds, and abrupt
visibility reductions.

..Dean.. 01/14/2024

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

ATTN...WFO...OKX...ALY...PHI...BGM...BUF...CTP...PBZ...

LAT...LON   41677844 42287758 42787492 42497443 41537461 40987535
            40647605 40357696 40117854 40177931 40437941 40977917
            41297889 41677844 

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