Alert archive / Iowa / Tornado Warnings in 2021

Tornado Warning 11, NWS Des Moines, IA

July 14, 2021Calhoun County, Greene County, Webster County, Iowa

NWS Des Moines, IA issued this tornado warning at Jul 14, 2021, 4:29 PM CDT for Calhoun County, Greene County, Webster County, Iowa. It was in force for 31 min. 1 report 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, 4:29 PM CDT (21:29 UTC)
Expired
Jul 14, 2021, 5:00 PM CDT
In force
31 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Tornado
Observed
Hail
0.75 in

Counties Calhoun County, IA, Greene County, IA, Webster County, IA

The radar

The Des Moines radar (KDMX), 83 km from the middle of the area, began a volume at 21:31 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

TimeReportWhereRemark
Jul 14, 4:46 PM CDTTORNADO1 Nw Gowrie, IADNR LAW ENFORCEMENT OFFICER REPORTS A TORNADO ALONG 340TH ST.

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.

IssuedProductOfficeLasted
Jul 14, 2:35 PM CDTTornado WatchSPC8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.5 hours before the alert went out and 193 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-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2021-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 967 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2021-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
967 J/kg
Mixed-layer CIN
-125 J/kg
Mixed-layer LCL
1201 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
-7 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

792 
WFUS53 KDMX 142129
TORDMX
IAC025-073-187-142200-
/O.NEW.KDMX.TO.W.0011.210714T2129Z-210714T2200Z/

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

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Northeastern Greene County in west central Iowa...
  Southwestern Webster County in central Iowa...
  Southeastern Calhoun County in west central Iowa...

* Until 500 PM CDT.

* At 428 PM CDT, a confirmed tornado was located 9 miles southeast of
  Rockwell City, moving east at 20 mph.

  HAZARD...Damaging tornado.

  SOURCE...Law enforcement confirmed tornado. At 422 pm law 
           enforcement reported a tornado between Lohrville and 
           Farmhamville.

  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.

* Locations impacted include...
  Gowrie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 4224 9454 4228 9456 4232 9454 4241 9417
      4214 9417
TIME...MOT...LOC 2128Z 268DEG 18KT 4228 9452 

TORNADO...OBSERVED
HAIL...<.75IN

$$

Small
2 follow-up statements
484 
WWUS53 KDMX 142143
SVSDMX

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

IAC073-142153-
/O.CAN.KDMX.TO.W.0011.000000T0000Z-210714T2200Z/
Greene IA-
443 PM CDT Wed Jul 14 2021

...THE TORNADO WARNING FOR NORTHEASTERN GREENE COUNTY IS CANCELLED...
    
The tornadic 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 900 PM CDT for central and
west central Iowa.

LAT...LON 4226 9438 4230 9440 4233 9438 4240 9417
      4221 9417
TIME...MOT...LOC 2143Z 266DEG 19KT 4230 9437 

$$

IAC025-187-142200-
/O.CON.KDMX.TO.W.0011.000000T0000Z-210714T2200Z/
Webster IA-Calhoun IA-
443 PM CDT Wed Jul 14 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM CDT FOR
SOUTHWESTERN WEBSTER AND SOUTHEASTERN CALHOUN COUNTIES...
    
At 443 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Gowrie, or 14 miles southeast of Rockwell City,
moving east at 20 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.

Locations impacted include...
  Gowrie.

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 4226 9438 4230 9440 4233 9438 4240 9417
      4221 9417
TIME...MOT...LOC 2143Z 266DEG 19KT 4230 9437 

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

$$

Small
682 
WWUS53 KDMX 142158
SVSDMX

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

IAC025-187-142208-
/O.EXP.KDMX.TO.W.0011.000000T0000Z-210714T2200Z/
Webster IA-Calhoun IA-
458 PM CDT Wed Jul 14 2021

...THE TORNADO WARNING FOR SOUTHWESTERN WEBSTER AND SOUTHEASTERN
CALHOUN COUNTIES WILL EXPIRE AT 500 PM CDT...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

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

LAT...LON 4226 9438 4230 9440 4233 9438 4240 9417
      4221 9417
TIME...MOT...LOC 2158Z 255DEG 30KT 4233 9421 

$$

Small

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 7:17 AM CDTSpecial Weather StatementDMXEmmet, Humboldt, Kossuth, Palo Alto, Pocahontas58 min
Jul 14, 8:08 AM CDTSevere Thunderstorm WarningDMXKossuth, Winnebago52 min
Jul 14, 8:24 AM CDTSpecial Weather StatementDMXButler, Cerro Gordo, Franklin, Hancock, Winnebago, Worth66 min
Jul 14, 8:39 AM CDTSevere Thunderstorm WarningDMXButler, Cerro Gordo, Franklin, Grundy, Hancock, Hardin and 1 more66 min
Jul 14, 8:43 AM CDTSevere Thunderstorm WarningDMXCerro Gordo, Hancock, Winnebago, Worth62 min
Jul 14, 8:49 AM CDTSevere Thunderstorm WarningDMXGrundy, Hardin, Marshall, Story, Tama56 min
Jul 14, 9:40 AM CDTSpecial Weather StatementDMXBlack Hawk, Bremer, Tama65 min
Jul 14, 3:55 PM CDTTornado WarningDMXCalhoun, Carroll, Greene35 min
Jul 14, 4:04 PM CDTTornado WarningDMXBoone, Hamilton, Story, Webster41 min
Jul 14, 4:23 PM CDTTornado WarningDMXFranklin, Hamilton, Hardin, Wright37 min
Jul 14, 4:29 PM CDTTornado Warning Tornado observedDMXHamilton, Hardin31 min
Jul 14, 4:30 PM CDTTornado WarningDMXButler30 min
Jul 14, 4:35 PM CDTTornado WarningDMXFranklin, Hardin40 min
Jul 14, 4:53 PM CDTTornado WarningDMXBremer, Butler37 min
Jul 14, 4:56 PM CDTTornado Warning Tornado observedDMXHamilton, Hardin25 min
Jul 14, 5:00 PM CDTTornado WarningDMXHamilton, Hardin, Story25 min
Jul 14, 5:18 PM CDTSevere Thunderstorm WarningDMXBlack Hawk, Bremer, Butler42 min
Jul 14, 5:18 PM CDTSevere Thunderstorm WarningDMXGrundy, Hardin42 min
Jul 14, 5:23 PM CDTTornado Warning Tornado observedDMXBlack Hawk, Bremer, Butler37 min
Jul 14, 5:49 PM CDTSevere Thunderstorm WarningDMXBlack Hawk, Bremer, Butler, Grundy41 min
Jul 14, 5:50 PM CDTTornado WarningDMXCerro Gordo25 min
Jul 14, 5:53 PM CDTTornado Warning Tornado observedDMXBlack Hawk, Bremer37 min
Jul 14, 5:58 PM CDTTornado WarningDMXCalhoun47 min
Jul 14, 6:02 PM CDTTornado WarningDMXBlack Hawk, Grundy, Marshall, Tama43 min
Jul 14, 6:42 PM CDTSevere Thunderstorm WarningDMXTama48 min
Jul 14, 6:42 PM CDTTornado WarningDMXWebster36 min
Jul 14, 6:55 PM CDTTornado WarningDMXTama19 min

Nearby

Tornado Warnings in Iowa, 2021Every tornado warning in 2021Tornadoes 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.