Severe Thunderstorm Watch 433

Issued

Aug 4, 2016, 4:44 PM CDT (21:44 UTC)

Expired

Aug 4, 2016, 10:55 PM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The La Crosse radar (KARX), 107 km from the middle of the area, began a volume at 21:48 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

10%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

40%

One or more gusts of 65 knots or more

10%

Ten or more severe hail reports

30%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

70%

• Mesoscale Discussion 1479Aug 4, 4:48 PM CDT
• Mesoscale Discussion 1480Aug 4, 7:17 PM CDT
• Mesoscale Discussion 1481Aug 4, 8:41 PM CDT

496 
WWUS20 KWNS 042142
SEL3  
SPC WW 042142
IAZ000-ILZ000-WIZ000-LMZ000-050500-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 433
NWS STORM PREDICTION CENTER NORMAN OK
445 PM CDT THU AUG 4 2016

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
  EASTERN IOWA
  NORTHWEST ILLINOIS
  SOUTHERN WISCONSIN
  LAKE MICHIGAN

* EFFECTIVE THIS THURSDAY AFTERNOON FROM 445 PM UNTIL MIDNIGHT
  CDT.

* PRIMARY THREATS INCLUDE...
  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
  ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE

SUMMARY...SCATTERED MULTICELLS AND MULTIPLE LINEAR BANDS OF STORMS
WILL PROGRESS EAST-SOUTHEASTWARD THROUGH THIS EVENING WITHIN A VERY
MOIST AND UNSTABLE ENVIRONMENT. DAMAGING WINDS SHOULD BE THE PRIMARY
HAZARD.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 105
STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH
NORTHWEST OF MADISON WISCONSIN TO 20 MILES WEST SOUTHWEST OF
CEDAR RAPIDS IOWA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

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 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM
MOTION VECTOR 29035.


...GUYER

Severe Thunderstorm Watches in Iowa, 2016Severe Thunderstorm Watches in Wisconsin, 2016Severe Thunderstorm Watches in Illinois, 2016Every severe thunderstorm watch in 2016

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.