Severe Thunderstorm Watch 340

Issued

Jun 16, 2017, 3:53 PM CDT (20:53 UTC)

Expired

Jun 16, 2017, 10:41 PM CDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Des Moines radar (KDMX), 174 km from the middle of the area, began a volume at 20:52 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

2%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

10%

Ten or more severe hail reports

50%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 1055Jun 16, 1:41 PM CDT
• Mesoscale Discussion 1057Jun 16, 3:29 PM CDT
• Mesoscale Discussion 1063Jun 16, 6:56 PM CDT

797 
WWUS20 KWNS 162051
SEL0  
SPC WW 162051
IAZ000-MNZ000-NEZ000-SDZ000-WIZ000-170300-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 340
NWS Storm Prediction Center Norman OK
355 PM CDT Fri Jun 16 2017

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Northern Iowa
  Southern Minnesota
  Extreme Northeast Nebraska
  Extreme Southeast South Dakota
  Southwest Wisconsin

* Effective this Friday afternoon and evening from 355 PM until
  1000 PM CDT.

* Primary threats include...
  Scattered large hail and isolated very large hail events to 2
    inches in diameter possible
  Scattered damaging wind gusts to 70 mph possible
  A tornado or two possible

SUMMARY...Thunderstorms will continue to develop over the watch area
this afternoon and early evening.  The strongest cells will be
capable of large hail and damaging winds.

The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 35 miles north
northwest of Sioux City IA to 35 miles northeast of Lonerock WI. For
a complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU0).

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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 338...WW 339...

AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
27030.

...Hart

Severe Thunderstorm Watches in Iowa, 2017Severe Thunderstorm Watches in Minnesota, 2017Severe Thunderstorm Watches in Wisconsin, 2017Every severe thunderstorm watch in 2017

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.