Severe Thunderstorm Watch 455

Issued

Aug 22, 2021, 3:36 PM CDT (20:36 UTC)

Expired

Aug 22, 2021, 9:00 PM CDT

In force

5 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Fargo/Grand Forks radar (KMVX), 110 km from the middle of the area, began a volume at 20:37 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

40%

One or more gusts of 65 knots or more

20%

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

70%

• Mesoscale Discussion 1576 Severe potential...watch likelyAug 22, 2:21 PM CDT
• Mesoscale Discussion 1578 Severe thunderstorm watch 455Aug 22, 5:59 PM CDT
• Mesoscale Discussion 1580 Tornado watch 457Aug 22, 8:40 PM CDT

737 
WWUS20 KWNS 222034
SEL5  
SPC WW 222034
NDZ000-SDZ000-230200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 455
NWS Storm Prediction Center Norman OK
330 PM CDT Sun Aug 22 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  central and eastern North Dakota
  northeastern South Dakota

* Effective this Sunday afternoon and evening from 330 PM until
  900 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...Scattered strong to severe thunderstorms, including a few
supercells, are expected to form late this afternoon in a corridor
initially extending from parts of north central North Dakota
south-southeastward into parts of central South Dakota.  These
storms will rapidly develop eastward toward the western Minnesota
state border through early evening.

The severe thunderstorm watch area is approximately along and 75
statute miles east and west of a line from 40 miles north northwest
of Devils Lake ND to 5 miles east southeast of Huron SD. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU5).

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 500. Mean storm motion vector
24035.

...Kerr

Severe Thunderstorm Watches in North Dakota, 2021Severe Thunderstorm Watches in South Dakota, 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.