Alert archive / Iowa / Tornado Warnings in 2021

Tornado Warning 19, NWS Des Moines, IA

July 14, 2021Cerro Gordo County, Iowa

NWS Des Moines, IA issued this tornado warning at Jul 14, 2021, 5:50 PM CDT for Cerro Gordo County, Iowa. It was in force for 25 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 14, 2021, 5:50 PM CDT (22:50 UTC)
Expired: Jul 14, 2021, 6:15 PM CDT
In force: 25 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Cerro Gordo County, IA

The radar

The Des Moines radar (KDMX), 150 km from the middle of the area, began a volume at 22:50 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.

What was reported inside it

Time	Report	Where	Remark
Jul 14, 6:05 PM CDT	TORNADO	1 Ne Rockwell, IA
Jul 14, 6:06 PM CDT	TORNADO	5 Ne Rockwell, IA	PUBLIC REPORT OF TORNADO ON GROUND.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

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

Minneapolis, MN (KMPX), launched 12:00Z, 10.8 hours before the alert went out and 209 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: 2820 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 1084 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -8 m²/s²
0-3 km storm-relative helicity: 69 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.3

Open this sounding in Storm Lab

The text

As transmitted.

786 
WFUS53 KDMX 142250
TORDMX
IAC033-142315-
/O.NEW.KDMX.TO.W.0019.210714T2250Z-210714T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
550 PM CDT Wed Jul 14 2021

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Southeastern Cerro Gordo County in north central Iowa...

* Until 615 PM CDT.
    
* At 550 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Rockwell, or 7 miles south of Mason City, moving
  east at 25 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This tornadic thunderstorm will remain over mainly rural areas of
  southeastern Cerro Gordo County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4294 9303 4298 9327 4307 9327 4310 9302
TIME...MOT...LOC 2250Z 272DEG 24KT 4303 9320 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

Small

1 follow-up statement

972 
WWUS53 KDMX 142319
SVSDMX

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

IAC033-142328-
/O.EXP.KDMX.TO.W.0019.000000T0000Z-210714T2315Z/
Cerro Gordo IA-
619 PM CDT Wed Jul 14 2021

...THE TORNADO WARNING FOR SOUTHEASTERN CERRO GORDO COUNTY HAS
EXPIRED...
        
The storm which prompted the warning has weakened below severe 
limits, and has exited the warned area. Therefore, the warning has 
been allowed to expire.  However gusty winds are still possible with 
this thunderstorm.

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

LAT...LON 4294 9303 4298 9327 4307 9327 4310 9302
TIME...MOT...LOC 2318Z 272DEG 24KT 4302 9295 

$$

Small

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, 5:18 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin	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, 5:53 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

Tornado Warnings in Iowa, 2021 Every tornado warning in 2021 Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.