SPC MD 1685

MD 1685 CONCERNING HEAVY SNOW FOR SOUTHERN WY...FAR SOUTHWEST SD...FAR NORTHWEST NE PANHANDLE

Mesoscale Discussion 1685
NWS Storm Prediction Center Norman OK
0334 AM CDT Tue Sep 08 2020

Areas affected...Southern WY...Far Southwest SD...Far Northwest NE
Panhandle

Concerning...Heavy snow 

Valid 080834Z - 081230Z

SUMMARY...Snowfall rates around 1"/hr are possible across lower
elevations over the next few hours. Rates of 2-3"/hr are possible
over higher elevations.

DISCUSSION...A strong shortwave trough continues to dig
south-southeastward through the eastern Great Basin toward the
central Rockies. Evolution of this shortwave is contributing to
strong forcing for ascent near and behind a vigorous cold front
pushing through the central Plains/central High Plains. Banded
precipitation has resulted from the central High Plains into the
central Plains over the past few hours, with moderate to heavy snow
occasionally reported in those areas where profiles are cold enough.

Based on recent observations and RAP forecast soundings, the area
from southwest WY northeastward into far southwest SD/far northwest
NE Panhandle is expected to be cold enough for snow over the next
few hours. Snowfall rates in these areas could approach 1"/hr across
the lower elevations and 2"-3"/hr over the higher terrain. This is
evidenced by recent storm reports indicating 6" to 8" of snow has
already fallen in Lawrence County SD (in the Black Hills).
Additionally, blizzard conditions were recently reported at RKS and
EMM in southwest WY.

..Mosier.. 09/08/2020

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

ATTN...WFO...UNR...CYS...RIW...SLC...

LAT...LON   41971066 43010852 43560522 44310373 43890278 42180430
            41190743 41031045 41971066 

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from SPC Forecast Products http://www.spc.noaa.gov/products/md/md1685.html