Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 99, NWS Des Moines, IA

August 26, 2021Appanoose County, Davis County, Wapello County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 26, 2021, 2:16 PM CDT for Appanoose County, Davis County, Wapello County, Iowa. It was in force for 44 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
Aug 26, 2021, 2:16 PM CDT (19:16 UTC)
Expired
Aug 26, 2021, 3:00 PM CDT
In force
44 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Appanoose County, IA, Davis County, IA, Wapello County, IA

The radar

The Des Moines radar (KDMX), 149 km from the middle of the area, began a volume at 19:15 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, 7.3 hours before the alert went out and 178 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 2021-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 458 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 2021-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 square meters per square second.1939Sfc1 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
458 J/kg
Mixed-layer CIN
-249 J/kg
Mixed-layer LCL
817 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
-15 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

615 
WUUS53 KDMX 261916
SVRDMX
IAC007-051-179-262000-
/O.NEW.KDMX.SV.W.0099.210826T1916Z-210826T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
216 PM CDT Thu Aug 26 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Davis County in southeastern Iowa...
  Southeastern Wapello County in southeastern Iowa...
  Southeastern Appanoose County in south central Iowa...

* Until 300 PM CDT.

* At 216 PM CDT, severe thunderstorms were located along a line
  extending from 6 miles west of Batavia to 6 miles north of
  Lancaster, moving east at 20 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.

* These severe thunderstorms will remain over mainly rural areas of
  Davis, southeastern Wapello and southeastern Appanoose Counties,
  including the following locations... Eldon, Agency, Floris,
  Pulaski, Drakesville, Bloomfield Municipal Airport, Moulton and
  Lake Wapello State Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4104 9236 4102 9218 4060 9218 4059 9279
TIME...MOT...LOC 1916Z 285DEG 19KT 4097 9228 4062 9257 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Donavon
3 follow-up statements
628 
WWUS53 KDMX 261933
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
233 PM CDT Thu Aug 26 2021

IAC007-051-179-262000-
/O.CON.KDMX.SV.W.0099.000000T0000Z-210826T2000Z/
Davis IA-Wapello IA-Appanoose IA-
233 PM CDT Thu Aug 26 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM CDT
FOR DAVIS...SOUTHEASTERN WAPELLO AND SOUTHEASTERN APPANOOSE
COUNTIES...

At 233 PM CDT, severe thunderstorms were located along a line
extending from near Batavia to 6 miles northeast of Lancaster, moving
east at 20 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...
Bloomfield, Eldon, Agency, Pulaski, Drakesville, Floris and
Bloomfield Municipal Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4102 9218 4060 9218 4059 9270 4104 9232
TIME...MOT...LOC 1933Z 285DEG 19KT 4095 9218 4060 9247 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Donavon
112 
WWUS53 KDMX 261947
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
247 PM CDT Thu Aug 26 2021

IAC007-261957-
/O.CAN.KDMX.SV.W.0099.000000T0000Z-210826T2000Z/
Appanoose IA-
247 PM CDT Thu Aug 26 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN APPANOOSE COUNTY
IS CANCELLED...

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

LAT...LON 4100 9218 4060 9218 4059 9263
TIME...MOT...LOC 1947Z 286DEG 16KT 4093 9210 4058 9239 

$$

IAC051-179-262000-
/O.CON.KDMX.SV.W.0099.000000T0000Z-210826T2000Z/
Davis IA-Wapello IA-
247 PM CDT Thu Aug 26 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM CDT
FOR DAVIS AND SOUTHEASTERN WAPELLO COUNTIES...

At 247 PM CDT, severe thunderstorms were located along a line
extending from near Libertyville to 6 miles north of Downing, moving
east at 20 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...
Bloomfield, Eldon, Pulaski, Floris and Bloomfield Municipal Airport. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4100 9218 4060 9218 4059 9263
TIME...MOT...LOC 1947Z 286DEG 16KT 4093 9210 4058 9239 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Donavon
766 
WWUS53 KDMX 262000
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
300 PM CDT Thu Aug 26 2021

IAC051-179-262010-
/O.EXP.KDMX.SV.W.0099.000000T0000Z-210826T2000Z/
Davis IA-Wapello IA-
300 PM CDT Thu Aug 26 2021

...THE SEVERE THUNDERSTORM WARNING FOR DAVIS AND SOUTHEASTERN WAPELLO
COUNTIES HAS EXPIRED...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning has been allowed to expire.

LAT...LON 4100 9218 4060 9218 4059 9263
TIME...MOT...LOC 2000Z 285DEG 19KT 4091 9202 4056 9231 

$$

Donavon

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 26, 3:30 AM CDTHeat AdvisoryDMXAdair, Adams, Appanoose, Audubon, Cass, Clarke and 16 more17 hr
Aug 26, 8:03 AM CDTSpecial Weather StatementDMXAudubon, Calhoun, Carroll, Pocahontas, Sac42 min
Aug 26, 8:18 AM CDTSevere Thunderstorm WarningDMXCalhoun, Carroll, Crawford, Greene, Sac42 min
Aug 26, 8:55 AM CDTSpecial Weather StatementDMXAdair, Audubon, Dallas, Guthrie65 min
Aug 26, 9:18 AM CDTSpecial Weather StatementDMXBoone, Hamilton, Webster57 min
Aug 26, 10:02 AM CDTSpecial Weather StatementDMXDallas, Jasper, Madison, Polk, Warren43 min
Aug 26, 12:29 PM CDTSpecial Weather StatementDMXBoone, Story46 min
Aug 26, 1:46 PM CDTSpecial Weather StatementDMXDavis, Wapello44 min
Aug 26, 3:03 PM CDTFlood WatchDMXBlack Hawk, Bremer, Butler, Calhoun, Cerro Gordo, Emmet and 13 more16 hr

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.