SPC MD 1650
MD 1650 CONCERNING SEVERE THUNDERSTORM WATCH 509... FOR SOUTHEASTERN WYOMING...NORTHEASTERN COLORADO...WESTERN NEBRASKA

Mesoscale Discussion 1650
NWS Storm Prediction Center Norman OK
0832 PM CDT Fri Jul 11 2025

Areas affected...southeastern Wyoming...northeastern
Colorado...western Nebraska

Concerning...Severe Thunderstorm Watch 509...

Valid 120132Z - 120300Z

The severe weather threat for Severe Thunderstorm Watch 509
continues.

SUMMARY...Threat for large hail and damaging wind continues in
WW509.

DISCUSSION...Outflow interactions from storms moving off of the high
terrain has led to a steady increase in thunderstorm activity across
northeastern Colorado into western Nebraska. Initial supercells have
been efficient at producing 1-1.5 (occasionally 2") hail. As storms
further congeal along outflow, the damaging wind risk may increase
through the evening across eastern Colorado into northwest Kansas.
Mode remains somewhat disorganized for now, with much of the
activity north of the front. For now, more discrete convection will
continue to pose a risk for large hail.

..Thornton.. 07/12/2025

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

ATTN...WFO...LBF...GLD...BOU...CYS...

LAT...LON   40850527 41460502 41570467 41680346 41690255 41620210
            41430170 41350154 41130127 40210135 39730186 39670304
            40090483 40100496 40850527 

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN

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https://www.spc.noaa.gov/products/md/md1650.html