Severe Thunderstorm Watch 419

Issued

Aug 10, 2021, 2:08 PM CDT (19:08 UTC)

Expired

Aug 10, 2021, 7:46 PM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

65 kt

The Quad Cities radar (KDVN), 95 km from the middle of the area, began a volume at 19:11 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

60%

One or more gusts of 65 knots or more

60%

Ten or more severe hail reports

40%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 1461 Severe potential...watch possibleAug 10, 1:12 PM CDT
• Mesoscale Discussion 1465 Severe potential...watch likelyAug 10, 3:10 PM CDT
• Mesoscale Discussion 1467 Severe thunderstorm watch 419...420Aug 10, 5:51 PM CDT

181 
WWUS20 KWNS 101904
SEL9  
SPC WW 101904
IAZ000-ILZ000-WIZ000-110100-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 419
NWS Storm Prediction Center Norman OK
205 PM CDT Tue Aug 10 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Eastern Iowa
  A small part of northwestern Illinois
  Southwestern Wisconsin

* Effective this Tuesday afternoon and evening from 205 PM until
  800 PM CDT.

* Primary threats include...
  Scattered damaging winds and isolated significant gusts to 75
    mph likely
  Scattered large hail events to 1.5 inches in diameter possible

SUMMARY...Thunderstorms are forming across parts of central and
northeastern Iowa, and these storms have the potential to increase
in both coverage and intensity through the afternoon.  The storm
environment appears favorable for storm clusters capable of
producing isolated significant severe outflow gusts to 75 mph and
isolated large hail.

The severe thunderstorm watch area is approximately along and 50
statute miles east and west of a line from 80 miles north northwest
of Dubuque IA to 20 miles west southwest of Burlington IA. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU9).

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 65 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
27025.

...Thompson

Severe Thunderstorm Watches in Iowa, 2021Severe Thunderstorm Watches in Wisconsin, 2021Severe Thunderstorm Watches in Illinois, 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.