Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 2, NWS Des Moines, IA

March 10, 2021Grundy County, Marshall County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Mar 10, 2021, 5:34 PM CST for Grundy County, Marshall County, Iowa. It was in force for 24 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: Mar 10, 2021, 5:34 PM CST (23:34 UTC)
Expired: Mar 10, 2021, 5:58 PM CST
In force: 24 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Grundy County, IA, Marshall County, IA

The radar

The Des Moines radar (KDMX), 107 km from the middle of the area, began a volume at 23:35 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
Mar 10, 2:46 PM CST	Tornado Watch	SPC	5 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.6 hours before the alert went out and 202 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 932 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 242 m²/s²
0-3 km storm-relative helicity: 292 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

142 
WUUS53 KDMX 102334
SVRDMX
IAC075-127-110015-
/O.NEW.KDMX.SV.W.0002.210310T2334Z-210311T0015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
534 PM CST Wed Mar 10 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Northern Marshall County in central Iowa...
  Central Grundy County in central Iowa...

* Until 615 PM CST.

* At 534 PM CST, a severe thunderstorm was located near Conrad, or 12
  miles southeast of Eldora, moving northeast at 65 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Grundy Center, Dike, Conrad, Holland, Stout and Morrison. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CST for central, north
central and northeastern Iowa.

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

&&

LAT...LON 4230 9270 4230 9277 4226 9280 4215 9296
      4221 9300 4226 9300 4256 9272 4255 9256
      4247 9255 4247 9254 4240 9253
TIME...MOT...LOC 2334Z 225DEG 55KT 4222 9295 

HAIL...1.00IN
WIND...60MPH
 
$$

Cogil

3 follow-up statements

189 
WWUS53 KDMX 102339
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
539 PM CST Wed Mar 10 2021

IAC127-102349-
/O.CAN.KDMX.SV.W.0002.000000T0000Z-210311T0015Z/
Marshall IA-
539 PM CST Wed Mar 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN MARSHALL COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 800 PM CST for central, north
central and northeastern Iowa.

LAT...LON 4230 9270 4230 9277 4226 9280 4222 9288
      4229 9296 4256 9272 4255 9256 4247 9255
      4247 9254 4240 9253
TIME...MOT...LOC 2339Z 225DEG 55KT 4228 9287 

$$

IAC075-110015-
/O.CON.KDMX.SV.W.0002.000000T0000Z-210311T0015Z/
Grundy IA-
539 PM CST Wed Mar 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CST
FOR CENTRAL GRUNDY COUNTY...

At 539 PM CST, a severe thunderstorm was located near Conrad, or 7
miles southwest of Grundy Center, moving northeast at 65 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Grundy Center, Dike, Conrad, Holland, Stout and Morrison. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CST for central, north
central and northeastern Iowa.

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

&&

LAT...LON 4230 9270 4230 9277 4226 9280 4222 9288
      4229 9296 4256 9272 4255 9256 4247 9255
      4247 9254 4240 9253
TIME...MOT...LOC 2339Z 225DEG 55KT 4228 9287 

HAIL...1.00IN
WIND...60MPH
 
$$

Cogil

664 
WWUS53 KDMX 102346
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
546 PM CST Wed Mar 10 2021

IAC075-110015-
/O.CON.KDMX.SV.W.0002.000000T0000Z-210311T0015Z/
Grundy IA-
546 PM CST Wed Mar 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CST
FOR NORTHEASTERN GRUNDY COUNTY...

At 546 PM CST, a severe thunderstorm was located over Grundy Center,
moving northeast at 70 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Grundy Center, Dike, Holland, Stout and Morrison. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM CST for central, north
central and northeastern Iowa.

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

&&

LAT...LON 4232 9273 4230 9277 4234 9288 4256 9272
      4255 9256 4247 9255 4247 9254 4240 9253
TIME...MOT...LOC 2346Z 223DEG 62KT 4238 9276 

HAIL...1.00IN
WIND...60MPH
 
$$

Cogil

096 
WWUS53 KDMX 102358
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
558 PM CST Wed Mar 10 2021

IAC075-110008-
/O.CAN.KDMX.SV.W.0002.000000T0000Z-210311T0015Z/
Grundy IA-
558 PM CST Wed Mar 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN GRUNDY COUNTY IS
CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However small hail and
gusty winds are still possible with this thunderstorm.

A Tornado Watch remains in effect until 800 PM CST for central, north
central and northeastern Iowa.

LAT...LON 4232 9273 4230 9277 4234 9288 4256 9272
      4255 9256 4247 9255 4247 9254 4240 9253
TIME...MOT...LOC 2357Z 225DEG 55KT 4252 9257 

$$

Cogil

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 10, 3:55 AM CST	Wind Advisory	DMX	Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 45 more	20 hr
Mar 10, 4:02 AM CST	Red Flag Warning	DMX	Adair, Adams, Audubon, Cass, Guthrie, Taylor	14 hr
Mar 10, 2:15 PM CST	High Wind Warning	DMX	Adair, Adams, Audubon, Carroll, Cass, Crawford and 4 more	4 hr
Mar 10, 5:18 PM CST	Severe Thunderstorm Warning	DMX	Clarke, Union	24 min
Mar 10, 5:36 PM CST	Severe Thunderstorm Warning	DMX	Clarke, Decatur, Lucas	39 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.