Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 67, NWS Des Moines, IA

July 9, 2021Adair County, Adams County, Cass County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 9, 2021, 11:56 PM CDT for Adair County, Adams County, Cass County, Iowa. It was in force for 49 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 9, 2021, 11:56 PM CDT (04:56 UTC)
Expired
Jul 10, 2021, 12:45 AM CDT
In force
49 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Adair County, IA, Adams County, IA, Cass County, IA

The radar

The Des Moines radar (KDMX), 118 km from the middle of the area, began a volume at 04:58 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.

IssuedProductOfficeLasted
Jul 9, 9:58 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 4.9 hours before the alert went out and 127 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 00:00Z on 2021-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2603 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2021-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
2603 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
1447 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
186 m²/s²
Significant tornado parameter
0.6
Supercell composite
8.1

Open this sounding in Storm Lab

The text

As transmitted.

625 
WUUS53 KDMX 100456
SVRDMX
IAC001-003-029-100545-
/O.NEW.KDMX.SV.W.0067.210710T0456Z-210710T0545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
1156 PM CDT Fri Jul 9 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Southern Cass County in southwestern Iowa...
  Adams County in southwestern Iowa...
  Southwestern Adair County in southwestern Iowa...

* Until 1245 AM CDT.

* At 1156 PM CDT, severe thunderstorms were located along a line
  extending from near Atlantic to near Oakland, moving southeast at
  30 mph.

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

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Atlantic around 1200 AM CDT.
  Griswold around 1215 AM CDT.

Other locations in the path of these severe thunderstorms include
Lake Icaria.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4093 9493 4116 9493 4116 9516 4136 9515
      4141 9496 4113 9447 4103 9447 4091 9490
TIME...MOT...LOC 0456Z 315DEG 26KT 4138 9508 4129 9530 

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

Ansorge
1 follow-up statement
969 
WWUS53 KDMX 100521
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
1221 AM CDT Sat Jul 10 2021

IAC001-003-029-100545-
/O.CON.KDMX.SV.W.0067.000000T0000Z-210710T0545Z/
Cass IA-Adams IA-Adair IA-
1221 AM CDT Sat Jul 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1245 AM CDT
FOR SOUTHERN CASS...ADAMS AND SOUTHWESTERN ADAIR COUNTIES...

At 1220 AM CDT, severe thunderstorms were located along a line 
extending from 9 miles south of Atlantic to near Elliott, moving 
southeast at 30 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
  Lake Icaria and Corning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4093 9493 4116 9493 4116 9516 4136 9515
      4141 9496 4113 9447 4103 9447 4091 9490
TIME...MOT...LOC 0520Z 315DEG 26KT 4127 9494 4118 9516 

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

Martin

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 9:16 PM CDTSevere Thunderstorm WarningDMXRinggold44 min
Jul 9, 9:31 PM CDTSevere Thunderstorm WarningDMXClarke, Decatur, Ringgold, Union15 min
Jul 9, 9:38 PM CDTSevere Thunderstorm WarningDMXRinggold52 min
Jul 9, 10:21 PM CDTSevere Thunderstorm WarningDMXRinggold39 min
Jul 9, 11:41 PM CDTSevere Thunderstorm WarningDMXAudubon, Cass49 min
Jul 10, 12:41 AM CDTSevere Thunderstorm WarningDMXAdair, Adams, Cass, Ringgold, Taylor, Union64 min
Jul 10, 2:49 PM CDTSpecial Weather StatementDMXCarroll, Crawford, Sac56 min
Jul 10, 4:36 PM CDTTornado WarningDMXDallas, Guthrie24 min
Jul 10, 5:00 PM CDTTornado WarningDMXDallas30 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.