Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 74, NWS Des Moines, IA

July 14, 2021Grundy County, Hardin County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 14, 2021, 5:18 PM CDT for Grundy County, Hardin County, Iowa. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 14, 2021, 5:18 PM CDT (22:18 UTC)
Expired: Jul 14, 2021, 6:00 PM CDT
In force: 42 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Possible
Hail: 1.75 in
Wind: 60.0 mph

Counties Grundy County, IA, Hardin County, IA

The radar

The Des Moines radar (KDMX), 77 km from the middle of the area, began a volume at 22:20 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 14, 2:35 PM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.3 hours before the alert went out and 234 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 573 J/kg
Mixed-layer CIN: -62 J/kg
Mixed-layer LCL: 1106 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 108 m²/s²
0-3 km storm-relative helicity: 139 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

As transmitted.

860 
WUUS53 KDMX 142218 RRA
SVRDMX
IAC075-083-142300-
/O.NEW.KDMX.SV.W.0074.210714T2218Z-210714T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
518 PM CDT Wed Jul 14 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Southern Hardin County in central Iowa...
  Western Grundy County in central Iowa...

* Until 600 PM CDT.

* At 518 PM CDT, a severe thunderstorm was located 10 miles southwest
  of Eldora, moving east at 40 mph.

  HAZARD...Golf ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           wind damage to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Eldora around 535 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for central Iowa.

For your protection move to an interior room on the lowest floor of a
building.


&&

LAT...LON 4221 9340 4234 9343 4251 9286 4221 9278
TIME...MOT...LOC 2218Z 251DEG 33KT 4229 9328 

TORNADO...POSSIBLE
HAIL...1.75IN
WIND...60MPH
 
$$

Fowle

2 follow-up statements

344 
WWUS53 KDMX 142233
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
533 PM CDT Wed Jul 14 2021

IAC075-083-142300-
/O.CON.KDMX.SV.W.0074.000000T0000Z-210714T2300Z/
Hardin IA-Grundy IA-
533 PM CDT Wed Jul 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR SOUTHEASTERN HARDIN AND WESTERN GRUNDY COUNTIES...

At 533 PM CDT, a severe thunderstorm was located near Eldora, moving
northeast at 40 mph.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Eldora, Conrad, Hubbard, Wellsburg, Union, Steamboat Rock, New
Providence, Beaman, Whitten, Pine Lake State Park and Eldora
Municipal Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for central Iowa.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4221 9330 4237 9331 4251 9286 4221 9278
TIME...MOT...LOC 2233Z 245DEG 34KT 4232 9314 

HAIL...1.25IN
WIND...60MPH
 
$$

Fowle

278 
WWUS53 KDMX 142250
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
550 PM CDT Wed Jul 14 2021

IAC075-083-142300-
/O.CON.KDMX.SV.W.0074.000000T0000Z-210714T2300Z/
Hardin IA-Grundy IA-
550 PM CDT Wed Jul 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR SOUTHEASTERN HARDIN AND WESTERN GRUNDY COUNTIES...

At 550 PM CDT, a severe thunderstorm was located near Grundy Center,
moving east at 65 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Conrad, Wellsburg, Beaman, Whitten and Pine Lake State Park. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for central Iowa.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4222 9305 4245 9305 4251 9286 4221 9278
TIME...MOT...LOC 2250Z 273DEG 59KT 4231 9283 

HAIL...0.75IN
WIND...60MPH
 
$$

Fowle

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 14, 7:17 AM CDT	Special Weather Statement	DMX	Emmet, Humboldt, Kossuth, Palo Alto, Pocahontas	58 min
Jul 14, 8:08 AM CDT	Severe Thunderstorm Warning	DMX	Kossuth, Winnebago	52 min
Jul 14, 8:24 AM CDT	Special Weather Statement	DMX	Butler, Cerro Gordo, Franklin, Hancock, Winnebago, Worth	66 min
Jul 14, 8:39 AM CDT	Severe Thunderstorm Warning	DMX	Butler, Cerro Gordo, Franklin, Grundy, Hancock, Hardin and 1 more	66 min
Jul 14, 8:43 AM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Hancock, Winnebago, Worth	62 min
Jul 14, 8:49 AM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin, Marshall, Story, Tama	56 min
Jul 14, 9:40 AM CDT	Special Weather Statement	DMX	Black Hawk, Bremer, Tama	65 min
Jul 14, 3:55 PM CDT	Tornado Warning	DMX	Calhoun, Carroll, Greene	35 min
Jul 14, 4:04 PM CDT	Tornado Warning	DMX	Boone, Hamilton, Story, Webster	41 min
Jul 14, 4:23 PM CDT	Tornado Warning	DMX	Franklin, Hamilton, Hardin, Wright	37 min
Jul 14, 4:29 PM CDT	Tornado Warning Tornado observed	DMX	Calhoun, Greene, Webster	31 min
Jul 14, 4:29 PM CDT	Tornado Warning Tornado observed	DMX	Hamilton, Hardin	31 min
Jul 14, 4:30 PM CDT	Tornado Warning	DMX	Butler	30 min
Jul 14, 4:35 PM CDT	Tornado Warning	DMX	Franklin, Hardin	40 min
Jul 14, 4:53 PM CDT	Tornado Warning	DMX	Bremer, Butler	37 min
Jul 14, 4:56 PM CDT	Tornado Warning Tornado observed	DMX	Hamilton, Hardin	25 min
Jul 14, 5:00 PM CDT	Tornado Warning	DMX	Hamilton, Hardin, Story	25 min
Jul 14, 5:18 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Bremer, Butler	42 min
Jul 14, 5:23 PM CDT	Tornado Warning Tornado observed	DMX	Black Hawk, Bremer, Butler	37 min
Jul 14, 5:49 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Bremer, Butler, Grundy	41 min
Jul 14, 5:50 PM CDT	Tornado Warning	DMX	Cerro Gordo	25 min
Jul 14, 5:53 PM CDT	Tornado Warning Tornado observed	DMX	Black Hawk, Bremer	37 min
Jul 14, 5:58 PM CDT	Tornado Warning	DMX	Calhoun	47 min
Jul 14, 6:02 PM CDT	Tornado Warning	DMX	Black Hawk, Grundy, Marshall, Tama	43 min
Jul 14, 6:42 PM CDT	Severe Thunderstorm Warning	DMX	Tama	48 min
Jul 14, 6:42 PM CDT	Tornado Warning	DMX	Webster	36 min
Jul 14, 6:55 PM CDT	Tornado Warning	DMX	Tama	19 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2021 Every severe thunderstorm warning in 2021

Sources

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.