SPC MD 1587

MD 1587 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR IDAHO INTO SOUTHWEST MONTANA

Mesoscale Discussion 1587
NWS Storm Prediction Center Norman OK
0804 PM CDT Wed Aug 26 2020

Areas affected...Idaho into southwest Montana

Concerning...Severe potential...Watch unlikely 

Valid 270104Z - 270300Z

Probability of Watch Issuance...5 percent

SUMMARY...Isolated strong to severe storms will remain possible
through sunset. Strong downburst winds remain the primary threat
associated with these storms. A watch remains unlikely.

DISCUSSION...Radar and satellite trends over the past 2 hours across
ID and southwest MT have shown a slight uptick in convective
coverage and intensity with several storms showing moderate to
strong cloud top cooling. The environment over this region remains
supportive of organized convection with upwards of 1000 J/kg MUCAPE
and 45 knot effective bulk shear. Although there is some inhibition
in place, orographic ascent has thus far been able to overcome this
limitation. Furthermore, increasing (albeit weak) ascent ahead of an
approaching shortwave trough to the west should help maintain
sufficient ascent for convection through the evening hours.
Low-level lapse rates across the region continue to support a strong
wind potential, and instances of severe hail can not be ruled out
given adequate instability, shear, and mid-level lapse rates. This
activity should gradually diminish after sunset this evening, and
the threat will remain too isolated to warrant a watch.

..Moore/Guyer.. 08/27/2020

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

ATTN...WFO...BYZ...RIW...TFX...SLC...PIH...MSO...BOI...LKN...

LAT...LON   42031713 43831701 45721458 46241347 45991129 45551010
            44461086 42941269 41941403 42031713 

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