Mesoscale Discussion 1056
NWS Storm Prediction Center Norman OK
1135 PM CDT Mon Jun 29 2020
Areas affected...Western Dakotas
Concerning...Tornado Watch 318...
Valid 300435Z - 300630Z
The severe weather threat for Tornado Watch 318 continues.
SUMMARY...Severe threat should remain focused across the western
DISCUSSION...Slow-moving squall line has gradually weakened as it
moved east across western ND. Trailing portion of this convection,
with a few discrete supercells, continue to develop along the cool
side of the boundary across the Black Hills region where isentropic
ascent is greatest. Latest model data suggests LLJ will remain
focused across western NE into western SD through early morning, and
this should contribute to additional convection, much of it
elevated, atop the cooler boundary layer. While elevated convection
should pose mostly a hail risk, lone supercell over Perkins County
SD may be rooted in the boundary layer as it lifts northeast along
the wind shift. Damaging winds, hail, and perhaps a brief tornado
remain possible with this activity.
Some consideration may be needed to extend the watch if ongoing
convection continues to progress northeast.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 44500433 46770205 46320138 44200247 44500433