SPC Severe Thunderstorm Watch 257
WW 257 SEVERE TSTM IA MN NE SD 010105Z - 010600Z



URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 257
NWS Storm Prediction Center Norman OK
805 PM CDT Sun May 31 2026

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of
Northwest Iowa
Southwest Minnesota
Northeast Nebraska
Southeast South Dakota

* Effective this Sunday night and Monday morning from 805 PM
until 100 AM CDT.

* Primary threats include...
Scattered large hail events to 1.5 inches in diameter possible
Isolated damaging wind gusts to 70 mph possible
A tornado or two possible

SUMMARY...A few supercells and severe multicells will be possible
through the evening. Large hail, locally damaging winds will remain
possible, and some tornado risk will exist particularly with storms
initiating/occurring near the boundary across the region.

The severe thunderstorm watch area is approximately along and 45
statute miles east and west of a line from 30 miles west northwest
of Worthington MN to 10 miles southeast of Sioux City IA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU7).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
29020.

...Guyer


Read more
https://www.spc.noaa.gov/products/watch/ww0257.html