Severe Thunderstorm Watch 453

Issued

Aug 20, 2021, 4:39 PM CDT (21:39 UTC)

Expired

Aug 20, 2021, 11:00 PM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Omaha radar (KOAX), 51 km from the middle of the area, began a volume at 21:38 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

5%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

20%

Ten or more severe hail reports

30%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

70%

• Mesoscale Discussion 1567 Severe potential...watch possibleAug 20, 1:51 PM CDT
• Mesoscale Discussion 1568 Severe potential...watch possibleAug 20, 3:57 PM CDT
• Mesoscale Discussion 1570 Severe thunderstorm watch 453Aug 20, 7:06 PM CDT
• Mesoscale Discussion 1572 Severe thunderstorm watch 454Aug 20, 9:37 PM CDT

951 
WWUS20 KWNS 202135
SEL3  
SPC WW 202135
IAZ000-KSZ000-NEZ000-210400-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 453
NWS Storm Prediction Center Norman OK
440 PM CDT Fri Aug 20 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Southwestern Iowa
  Northeastern Kansas
  Eastern Nebraska

* Effective this Friday afternoon and evening from 440 PM until
  1100 PM CDT.

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

SUMMARY...Scattered severe storms are expected along and ahead of a
cold front across eastern Nebraska and northeastern Kansas through
late evening.  The storm environment favors a mix of supercells and
multicell clusters capable of producing damaging winds and isolated
large hail.  The stronger embedded supercells/circulations may
produce an isolated tornado or two through early evening.

The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 25 miles northwest of
Denison IA to 25 miles west southwest of Manhattan KS. 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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 451...WW 452...

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 600. Mean storm motion vector
27025.

...Thompson

Severe Thunderstorm Watches in Nebraska, 2021Severe Thunderstorm Watches in Kansas, 2021Severe Thunderstorm Watches in Iowa, 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.