Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 3, NWS Des Moines, IA

March 10, 2021Clarke County, Decatur County, Lucas County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Mar 10, 2021, 5:36 PM CST for Clarke County, Decatur County, Lucas County, Iowa. It was in force for 39 min. 3 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: Mar 10, 2021, 5:36 PM CST (23:36 UTC)
Expired: Mar 10, 2021, 6:15 PM CST
In force: 39 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Clarke County, IA, Decatur County, IA, Lucas County, IA

The radar

The Des Moines radar (KDMX), 90 km from the middle of the area, began a volume at 23:35 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
Mar 10, 5:49 PM CST	HAIL 1	1 E Osceola, IA	RELAYED FROM BROADCAST MEDIA THROUGH SNAPMAP. ESTIMATED FROM PICTURE.
Mar 10, 5:50 PM CST	HAIL 0.75	1 Ne Osceola, IA	REPORT FROM MPING: DIME (0.75 IN.).
Mar 10, 5:50 PM CST	HAIL 1	1 Ene Osceola, IA	GROUND WHITE - MOSTLY SMALLER STONES BUT A FEW STONES TO 1 INCH IN DIAMETER.

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

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.6 hours before the alert went out and 214 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: 178 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 794 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 293 m²/s²
0-3 km storm-relative helicity: 400 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.4

Open this sounding in Storm Lab

The text

As transmitted.

914 
WUUS53 KDMX 102336
SVRDMX
IAC039-053-117-110015-
/O.NEW.KDMX.SV.W.0003.210310T2336Z-210311T0015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
536 PM CST Wed Mar 10 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Northwestern Lucas County in south central Iowa...
  Northwestern Decatur County in south central Iowa...
  Central Clarke County in south central Iowa...

* Until 615 PM CST.

* At 536 PM CST, a severe thunderstorm was located near Sun Valley
  Lake, or 13 miles northwest of Leon, moving northeast at 70 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Osceola, Lakeside Casino and Grand River. 

This includes Interstate 35 between mile markers 24 and 40.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4074 9401 4086 9402 4090 9401 4116 9374
      4116 9339
TIME...MOT...LOC 2336Z 224DEG 60KT 4085 9397 

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

Cogil

3 follow-up statements

884 
WWUS53 KDMX 102348
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
548 PM CST Wed Mar 10 2021

IAC053-102358-
/O.CAN.KDMX.SV.W.0003.000000T0000Z-210311T0015Z/
Decatur IA-
548 PM CST Wed Mar 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN DECATUR COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4090 9378 4097 9393 4116 9374 4116 9339
TIME...MOT...LOC 2348Z 224DEG 60KT 4100 9378 

$$

IAC039-117-110015-
/O.CON.KDMX.SV.W.0003.000000T0000Z-210311T0015Z/
Lucas IA-Clarke IA-
548 PM CST Wed Mar 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CST
FOR NORTHWESTERN LUCAS AND CENTRAL CLARKE COUNTIES...

At 548 PM CST, a severe thunderstorm was located over Osceola, moving
northeast at 70 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...
Osceola and Lakeside Casino. 

This includes Interstate 35 between mile markers 26 and 40.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4090 9378 4097 9393 4116 9374 4116 9339
TIME...MOT...LOC 2348Z 224DEG 60KT 4100 9378 

HAIL...1.00IN
WIND...60MPH
 
$$

Cogil

075 
WWUS53 KDMX 110000
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
600 PM CST Wed Mar 10 2021

IAC039-117-110015-
/O.CON.KDMX.SV.W.0003.000000T0000Z-210311T0015Z/
Lucas IA-Clarke IA-
600 PM CST Wed Mar 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CST
FOR NORTHWESTERN LUCAS AND NORTHEASTERN CLARKE COUNTIES...

At 600 PM CST, a severe thunderstorm was located 13 miles northeast
of Osceola, moving northeast at 70 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.

This severe thunderstorm will remain over mainly rural areas of
northwestern Lucas and northeastern Clarke Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4102 9360 4108 9372 4116 9367 4116 9339
TIME...MOT...LOC 0000Z 224DEG 61KT 4114 9357 

HAIL...1.00IN
WIND...60MPH
 
$$

Cogil

117 
WWUS53 KDMX 110011
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
611 PM CST Wed Mar 10 2021

IAC039-117-110020-
/O.EXP.KDMX.SV.W.0003.000000T0000Z-210311T0015Z/
Lucas IA-Clarke IA-
611 PM CST Wed Mar 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN LUCAS AND
NORTHEASTERN CLARKE COUNTIES WILL EXPIRE AT 615 PM CST...
        
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.

LAT...LON 4102 9360 4108 9372 4116 9367 4116 9339
TIME...MOT...LOC 0010Z 224DEG 60KT 4126 9342 

$$

Cogil

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 10, 3:55 AM CST	Wind Advisory	DMX	Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 45 more	20 hr
Mar 10, 4:02 AM CST	Red Flag Warning	DMX	Adair, Adams, Audubon, Cass, Guthrie, Taylor	14 hr
Mar 10, 2:15 PM CST	High Wind Warning	DMX	Adair, Adams, Audubon, Carroll, Cass, Crawford and 4 more	4 hr
Mar 10, 5:18 PM CST	Severe Thunderstorm Warning	DMX	Clarke, Union	24 min
Mar 10, 5:34 PM CST	Severe Thunderstorm Warning	DMX	Grundy, Marshall	24 min

Nearby

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