Alert archive / Iowa / Tornado Warnings in 2021

Tornado Warning 3, NWS Des Moines, IA

June 20, 2021Mahaska County, Marion County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 20, 2021, 6:37 PM CDT for Mahaska County, Marion County, Iowa. It was in force for 23 min. 1 report 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 20, 2021, 6:37 PM CDT (23:37 UTC)
Expired
Jun 20, 2021, 7:00 PM CDT
In force
23 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

Counties Mahaska County, IA, Marion County, IA

The radar

The Des Moines radar (KDMX), 74 km from the middle of the area, began a volume at 23:37 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

TimeReportWhereRemark
Jun 20, 6:43 PM CDTTORNADO2 Nnw Pella, IAPICTURE ON SOCIAL MEDIA.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 20, 4:01 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.6 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2060 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
84 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

787 
WFUS53 KDMX 202337
TORDMX
IAC123-125-210000-
/O.NEW.KDMX.TO.W.0003.210620T2337Z-210621T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
637 PM CDT Sun Jun 20 2021

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Northeastern Marion County in south central Iowa...
  Northwestern Mahaska County in south central Iowa...

* Until 700 PM CDT.
    
* At 637 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Pella, moving east at 25 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Pella around 640 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Des Moines .

&&

LAT...LON 4141 9306 4148 9302 4144 9276 4132 9281
TIME...MOT...LOC 2337Z 285DEG 20KT 4143 9296 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

REV
3 follow-up statements
781 
WWUS53 KDMX 202342
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
642 PM CDT Sun Jun 20 2021

IAC123-125-210000-
/O.CON.KDMX.TO.W.0003.000000T0000Z-210621T0000Z/
Marion IA-Mahaska IA-
642 PM CDT Sun Jun 20 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR
NORTHEASTERN MARION AND NORTHWESTERN MAHASKA COUNTIES...
        
At 641 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Pella, moving east at 25 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Weather spotters reported a funnel cloud 2 WNW Pella at 
         6:39 pm.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
northeastern Marion and northwestern Mahaska Counties, including the
following locations... Pella Municipal Airport and Elk Rock State
Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4141 9306 4148 9302 4144 9276 4132 9281
TIME...MOT...LOC 2341Z 285DEG 20KT 4142 9292 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

REV
313 
WWUS53 KDMX 202345
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
645 PM CDT Sun Jun 20 2021

IAC123-125-210000-
/O.CON.KDMX.TO.W.0003.000000T0000Z-210621T0000Z/
Marion IA-Mahaska IA-
645 PM CDT Sun Jun 20 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR
NORTHEASTERN MARION AND NORTHWESTERN MAHASKA COUNTIES...
        
At 645 PM CDT, a confirmed large and extremely dangerous tornado was
located over Pella, moving east at 25 mph.

This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

HAZARD...Damaging tornado.

SOURCE...Radar confirmed tornado.

IMPACT...You are in a life-threatening situation. Flying debris may 
         be deadly to those caught without shelter. Mobile homes 
         will be destroyed. Considerable damage to homes, 
         businesses, and vehicles is likely and complete destruction 
         is possible.

Locations impacted include...
Pella, Lake Red Rock, Pella Municipal Airport and Elk Rock State
Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, TAKE COVER NOW! Move
to a basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4141 9306 4148 9302 4144 9276 4132 9281
TIME...MOT...LOC 2345Z 285DEG 20KT 4141 9289 

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CONSIDERABLE
HAIL...1.00IN

$$

REV
318 
WWUS53 KDMX 202352
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
652 PM CDT Sun Jun 20 2021

IAC123-125-210000-
/O.CON.KDMX.TO.W.0003.000000T0000Z-210621T0000Z/
Marion IA-Mahaska IA-
652 PM CDT Sun Jun 20 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR
NORTHEASTERN MARION AND NORTHWESTERN MAHASKA COUNTIES...
        
At 652 PM CDT, a confirmed large and extremely dangerous tornado was
located near Pella, moving east at 30 mph.

This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

HAZARD...Damaging tornado.

SOURCE...Radar confirmed tornado.

IMPACT...You are in a life-threatening situation. Flying debris may 
         be deadly to those caught without shelter. Mobile homes 
         will be destroyed. Considerable damage to homes, 
         businesses, and vehicles is likely and complete destruction 
         is possible.

Locations impacted include...
Pella, Lake Red Rock and Pella Municipal Airport. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, TAKE COVER NOW! Move
to a basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

If a tornado or other severe weather is spotted, report it to the
National Weather Service or your local nearest law enforcement agency
who will send your report. This act may save lives of others in the
path of dangerous weather.

&&

LAT...LON 4139 9300 4147 9298 4144 9276 4132 9281
TIME...MOT...LOC 2352Z 285DEG 26KT 4140 9286 

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CONSIDERABLE
HAIL...1.00IN

$$

REV

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 3:38 PM CDTSpecial Weather StatementDMXDallas37 min
Jun 20, 4:20 PM CDTSevere Thunderstorm WarningDMXClarke, Madison, Union55 min
Jun 20, 4:47 PM CDTSevere Thunderstorm WarningDMXJasper43 min
Jun 20, 4:53 PM CDTSevere Thunderstorm WarningDMXClarke, Decatur, Ringgold, Union52 min
Jun 20, 4:54 PM CDTSevere Thunderstorm WarningDMXBremer, Butler, Franklin51 min
Jun 20, 5:33 PM CDTSevere Thunderstorm WarningDMXJasper, Poweshiek42 min
Jun 20, 5:35 PM CDTSevere Thunderstorm WarningDMXClarke, Decatur, Lucas, Wayne40 min
Jun 20, 5:55 PM CDTSevere Thunderstorm WarningDMXJasper, Mahaska, Marion50 min
Jun 20, 5:59 PM CDTSevere Thunderstorm WarningDMXDecatur, Wayne46 min
Jun 20, 6:04 PM CDTTornado WarningDMXDecatur26 min
Jun 20, 6:13 PM CDTSevere Thunderstorm WarningDMXPoweshiek62 min
Jun 20, 6:15 PM CDTSevere Thunderstorm WarningDMXDecatur, Wayne30 min
Jun 20, 6:20 PM CDTSevere Thunderstorm WarningDMXBlack Hawk55 min
Jun 20, 6:43 PM CDTSevere Thunderstorm WarningDMXDecatur, Wayne47 min
Jun 20, 6:59 PM CDTTornado WarningDMXMahaska, Marion31 min

Nearby

Tornado Warnings in Iowa, 2021Every tornado warning in 2021Tornadoes 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.