Severe Thunderstorm Watch 276

Issued

Jun 17, 2021, 3:50 PM CDT (20:50 UTC)

Expired

Jun 17, 2021, 10:00 PM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

70 kt

The La Crosse radar (KARX), 57 km from the middle of the area, began a volume at 20:51 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Two or more tornadoes

20%

One or more EF2 to EF5 tornadoes

10%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

40%

Ten or more severe hail reports

40%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 989 Severe potential...watch likelyJun 17, 2:57 PM CDT
• Mesoscale Discussion 990 Severe thunderstorm watch 276Jun 17, 7:02 PM CDT
• Mesoscale Discussion 991 Severe thunderstorm watch 276Jun 17, 9:01 PM CDT

173 
WWUS20 KWNS 172047
SEL6  
SPC WW 172047
IAZ000-MNZ000-WIZ000-180300-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 276
NWS Storm Prediction Center Norman OK
350 PM CDT Thu Jun 17 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  North-central and northeast Iowa
  Southeast Minnesota
  Southwest to south-central Wisconsin

* Effective this Thursday afternoon and evening from 350 PM until
  1000 PM CDT.

* Primary threats include...
  Scattered damaging winds and isolated significant gusts to 80
    mph possible
  Scattered large hail and isolated very large hail events to 2
    inches in diameter possible
  A tornado or two possible

SUMMARY...A couple supercells may emanate out of a swath of
pre-frontal high-based thunderstorms, or they may consolidate into
an east-southeast moving cluster through mid-evening.

The severe thunderstorm watch area is approximately along and 75
statute miles east and west of a line from 5 miles north northwest
of Camp Douglas WI to 45 miles east southeast of Fort Dodge IA. For
a complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU6).

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
2 inches. Extreme turbulence and surface wind gusts to 70 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
29035.

...Grams

Severe Thunderstorm Watches in Iowa, 2021Severe Thunderstorm Watches in Wisconsin, 2021Severe Thunderstorm Watches in Minnesota, 2021Every severe thunderstorm watch in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.