Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 72, NWS Des Moines, IA

July 14, 20215 counties in Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 14, 2021, 8:49 AM CDT for 5 counties in Iowa. It was in force for 56 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, 8:49 AM CDT (13:49 UTC)
Expired
Jul 14, 2021, 9:45 AM CDT
In force
56 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Grundy County, IA, Hardin County, IA, Marshall County, IA, Story County, IA, Tama County, IA

The radar

The Des Moines radar (KDMX), 100 km from the middle of the area, began a volume at 13:51 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 nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 1.8 hours before the alert went out and 196 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, Davenport, at 12:00Z on 2021-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 573 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, Davenport, at 12:00Z on 2021-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 square meters per square second.19395878Sfc1 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
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.

099 
WUUS53 KDMX 141349
SVRDMX
IAC075-083-127-169-171-141445-
/O.NEW.KDMX.SV.W.0072.210714T1349Z-210714T1445Z/

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

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Eastern Story County in central Iowa...
  Marshall County in central Iowa...
  Hardin County in central Iowa...
  Tama County in central Iowa...
  Grundy County in central Iowa...

* Until 945 AM CDT.

* At 848 AM CDT, severe thunderstorms were located along a line
  extending from 6 miles southeast of Iowa Falls to 6 miles northeast
  of Baxter, moving east at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated. At 841 AM emergency management 
           also reported trees down on power lines in Nevada.

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

* Severe thunderstorms will be near...
  Eldora around 855 AM CDT.

Other locations in the path of these severe thunderstorms include
Meskwaki Casino, Toledo and Tama.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4187 9240 4186 9332 4239 9346 4256 9272
      4256 9257 4240 9253 4230 9253 4230 9251
TIME...MOT...LOC 1348Z 251DEG 23KT 4245 9317 4189 9306 

HAIL...<.75IN
WIND...60MPH
 
$$

Small
2 follow-up statements
560 
WWUS53 KDMX 141408
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
908 AM CDT Wed Jul 14 2021

IAC169-141417-
/O.CAN.KDMX.SV.W.0072.000000T0000Z-210714T1445Z/
Story IA-
908 AM CDT Wed Jul 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN STORY COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 300 PM CDT for
central, north central and northeastern Iowa.

LAT...LON 4186 9309 4243 9326 4256 9272 4256 9257
      4240 9253 4230 9253 4230 9251 4187 9240
TIME...MOT...LOC 1407Z 250DEG 24KT 4248 9298 4192 9287 

$$

IAC075-083-127-171-141445-
/O.CON.KDMX.SV.W.0072.000000T0000Z-210714T1445Z/
Marshall IA-Hardin IA-Tama IA-Grundy IA-
908 AM CDT Wed Jul 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 AM CDT
FOR MARSHALL...SOUTHEASTERN HARDIN...TAMA AND GRUNDY COUNTIES...

At 907 AM CDT, severe thunderstorms were scattered along a line 
extending from 6 miles southeast of Ackley to 8 miles south of 
Marshalltown, moving east at 25 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
  Meskwaki Casino, Toledo, Tama and Dike.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4186 9309 4243 9326 4256 9272 4256 9257
      4240 9253 4230 9253 4230 9251 4187 9240
TIME...MOT...LOC 1407Z 250DEG 24KT 4248 9298 4192 9287 

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

Small
313 
WWUS53 KDMX 141449
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
949 AM CDT Wed Jul 14 2021

IAC075-083-127-171-141458-
/O.EXP.KDMX.SV.W.0072.000000T0000Z-210714T1445Z/
Marshall IA-Hardin IA-Tama IA-Grundy IA-
949 AM CDT Wed Jul 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR MARSHALL...SOUTHEASTERN
HARDIN...TAMA AND GRUNDY COUNTIES HAS EXPIRED...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore, the warning has
been allowed to expire.  However gusty winds are still possible with
these thunderstorms.

A Severe Thunderstorm Watch remains in effect until 300 PM CDT for
central, north central and northeastern Iowa.

LAT...LON 4186 9309 4243 9326 4256 9272 4256 9257
      4240 9253 4230 9253 4230 9251 4187 9240
TIME...MOT...LOC 1448Z 258DEG 31KT 4255 9251 4199 9240 

$$

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, 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 observedDMXCalhoun, Greene, Webster31 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

Severe Thunderstorm Warnings in Iowa, 2021Every 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.