Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 46, NWS Des Moines, IA

June 22, 2021Dallas County, Polk County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jun 22, 2021, 4:59 PM CDT for Dallas County, Polk County, Iowa. It was in force for 46 min. 9 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: Jun 22, 2021, 4:59 PM CDT (21:59 UTC)
Expired: Jun 22, 2021, 5:45 PM CDT
In force: 46 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Dallas County, IA, Polk County, IA

The radar

The Des Moines radar (KDMX), 20 km from the middle of the area, began a volume at 21:59 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
Jun 22, 5:22 PM CDT	HAIL 0.88	Grimes, IA
Jun 22, 5:25 PM CDT	HAIL 1	1 Nnw Grimes, IA	NICKEL TO QUARTER SIZE HAIL.
Jun 22, 5:28 PM CDT	TSTM WND GST 60	Waukee, IA
Jun 22, 5:30 PM CDT	HAIL 1	1 Se Grimes, IA	REPORT FROM MPING: QUARTER (1.00 IN.).
Jun 22, 5:33 PM CDT	HAIL 1	1 Nnw Grimes, IA	TIME ESTIMATED BY RADAR.
Jun 22, 5:35 PM CDT	HAIL 1	2 W Johnston, IA	REPORT FROM MPING: QUARTER (1.00 IN.).
Jun 22, 5:38 PM CDT	TSTM WND GST 66	2 Se Waukee, IA	PERSONAL WEATHER STATION.
Jun 22, 5:39 PM CDT	HAIL 1	1 Wnw Urbandale, IA
Jun 22, 5:45 PM CDT	HAIL 1	1 Nw Clive, IA	LOTS OF QUARTER SIZED HAIL.

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, 10.0 hours before the alert went out and 205 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1910 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 259 m²/s²
0-3 km storm-relative helicity: 324 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

703 
WUUS53 KDMX 222159
SVRDMX
IAC049-153-222245-
/O.NEW.KDMX.SV.W.0046.210622T2159Z-210622T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
459 PM CDT Tue Jun 22 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Northwestern Polk County in central Iowa...
  Northeastern Dallas County in central Iowa...

* Until 545 PM CDT.

* At 459 PM CDT, a severe thunderstorm was located near Dallas
  Center, or near Perry, moving east at 25 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 be near...
  Dallas Center around 505 PM CDT.

Other locations in the path of this severe thunderstorm include
Waukee, Granger, Urbandale, Saylorville Lake, Grimes, Polk City, West
Des Moines, Johnston and Clive.

This includes Interstate 80 between mile markers 120 and 122, and
between mile markers 125 and 128.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4173 9414 4182 9407 4179 9368 4156 9379
TIME...MOT...LOC 2159Z 285DEG 23KT 4176 9403 

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

Krull

3 follow-up statements

152 
WWUS53 KDMX 222215
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
515 PM CDT Tue Jun 22 2021

IAC049-153-222245-
/O.CON.KDMX.SV.W.0046.000000T0000Z-210622T2245Z/
Polk IA-Dallas IA-
515 PM CDT Tue Jun 22 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM CDT
FOR WEST CENTRAL POLK AND NORTHEASTERN DALLAS COUNTIES...

At 515 PM CDT, a severe thunderstorm was located near Granger, or
near Grimes, moving southeast at 30 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...
  Waukee, Saylorville Lake, Urbandale, Grimes, Jordan Creek Town 
  Center, West Des Moines, Johnston and Clive.

This includes Interstate 80 between mile markers 121 and 122, and
between mile markers 125 and 128.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4170 9401 4179 9395 4177 9369 4156 9379
TIME...MOT...LOC 2215Z 297DEG 24KT 4171 9389 

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

Krull

409 
WWUS53 KDMX 222224
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
524 PM CDT Tue Jun 22 2021

IAC049-153-222245-
/O.CON.KDMX.SV.W.0046.000000T0000Z-210622T2245Z/
Polk IA-Dallas IA-
524 PM CDT Tue Jun 22 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM CDT
FOR WEST CENTRAL POLK AND EAST CENTRAL DALLAS COUNTIES...

At 524 PM CDT, a severe thunderstorm was located over Grimes, moving
east at 25 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

Locations impacted include...
West Des Moines, Urbandale, Johnston, Clive, Waukee, Grimes and
Jordan Creek Town Center.

This includes Interstate 80 between mile markers 121 and 122, and
between mile markers 125 and 128.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4168 9394 4177 9390 4171 9372 4156 9379
TIME...MOT...LOC 2224Z 285DEG 23KT 4169 9381 

HAIL...1.50IN
WIND...60MPH
 
$$

Krull

820 
WWUS53 KDMX 222228
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
528 PM CDT Tue Jun 22 2021

IAC049-153-222245-
/O.CON.KDMX.SV.W.0046.000000T0000Z-210622T2245Z/
Polk IA-Dallas IA-
528 PM CDT Tue Jun 22 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 545 PM CDT
FOR WEST CENTRAL POLK AND EAST CENTRAL DALLAS COUNTIES...

At 527 PM CDT, a severe thunderstorm was located over Grimes, moving
east at 25 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated. Trained spotters have reported quarter 
         size hail with this storm already. 

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

Locations impacted include...
West Des Moines, Urbandale, Johnston, Clive, Waukee, Grimes and
Jordan Creek Town Center.

This includes Interstate 80 between mile markers 121 and 122, and
between mile markers 125 and 128.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4168 9394 4177 9390 4171 9372 4156 9379
TIME...MOT...LOC 2227Z 285DEG 23KT 4168 9378 

HAIL...1.50IN
WIND...60MPH
 
$$

Krull

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 22, 5:22 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Sac	38 min
Jun 22, 5:30 PM CDT	Severe Thunderstorm Warning	DMX	Polk	45 min
Jun 22, 5:50 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun	40 min
Jun 22, 5:52 PM CDT	Special Weather Statement	DMX	Poweshiek	23 min
Jun 22, 5:58 PM CDT	Severe Thunderstorm Warning	DMX	Polk, Warren	47 min
Jun 22, 6:09 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Calhoun, Carroll, Greene, Webster	51 min
Jun 22, 6:30 PM CDT	Severe Thunderstorm Warning	DMX	Lucas, Marion, Warren	45 min
Jun 22, 6:33 PM CDT	Severe Thunderstorm Warning	DMX	Carroll, Greene	42 min
Jun 22, 6:42 PM CDT	Special Weather Statement	DMX	Tama	63 min
Jun 22, 6:49 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Guthrie	41 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.