MD 1413 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR MUCH OF WESTERN/CENTRAL MONTANA AND A SMALL PART OF NORTHEASTERN IDAHO

Mesoscale Discussion 1413
NWS Storm Prediction Center Norman OK
0253 PM CDT Thu Aug 06 2020

Areas affected...much of western/central Montana and a small part of
northeastern Idaho

Concerning...Severe potential...Watch unlikely 

Valid 061953Z - 062200Z

Probability of Watch Issuance...20 percent

SUMMARY...High-based convection capable of damaging wind gusts will
expand northeastward across much of the discussion area this
afternoon/early evening.  A WW issuance is not anticipated.

DISCUSSION...Lightning-producing convection has deepened within a
regime characterized by deep southwesterly flow aloft.  Steep low-
and mid-level lapse rates are in place across the region, with
values exceeding 9 C/km - especially in areas undisturbed by
convective downdrafts where temperatures are currently 80+ F.  The
lapse rates and appreciable storm movement will allow for occasional
downbursts near convection that could produce wind damage -
especially near clusters or linear segments that can organize
through the early evening.  Lift associated with mid-level shortwave
troughs migrating across the region should also promote convective
development through the afternoon as well.  The threat should remain
isolated enough to preclude any WW issuances, although convective
trends will be monitored.

..Cook/Kerr.. 08/06/2020

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

ATTN...WFO...BYZ...GGW...RIW...TFX...MSO...

LAT...LON   48311024 48461146 48081285 47351405 46091442 44981415
            44731239 45051008 45170854 45620749 46740759 47970881
            48311024 

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