MD 1502 CONCERNING SEVERE THUNDERSTORM WATCH 475… FOR SOUTHERN SD INTO NORTHERN NE
Mesoscale Discussion 1502
NWS Storm Prediction Center Norman OK
0239 AM CDT Wed Jul 12 2023
Areas affected...southern SD into northern NE
Concerning...Severe Thunderstorm Watch 475...
Valid 120739Z - 120915Z
The severe weather threat for Severe Thunderstorm Watch 475
continues.
SUMMARY...A thunderstorm cluster near the Nebraska/South Dakota
border is expected to pose a risk for damaging gusts greater than 65
mph through early morning.
DISCUSSION...A cluster of storm over south-central SD/north-central
NE has intensified over the past 30 minutes or so. Most recently, a
severe gust to 62 kt was observed at KVTN. IR satellite imagery also
is showing some modest cloud top cooling. This cluster is moving
southeast into the axis of a stronger southerly low-level jet of
around 25-30 kt. This should aid in further organization amid
moderate to strong instability (2000-3000 J/kg MUCAPE) and effective
shear magnitudes greater than 55 kt. This organizing cluster should
promote development of a fast-moving bowing MCS, and the better
chances for a swath of damaging gust potential will exist across
southeast SD near the NE state line into north-central and northeast
NE through early morning.
..Leitman.. 07/12/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FSD...OAX...ABR...GID...LBF...UNR...
LAT...LON 42590076 43100065 43620000 43959877 43809771 43289675
42669634 41799615 41679636 41539711 41589787 41849925
42370054 42590076
