Alert archive / Iowa / Tornado Warnings in 2023

Tornado Warning 13, NWS Des Moines, IA

April 19, 2023Jasper County, Poweshiek County, Iowa

NWS Des Moines, IA issued this tornado warning at Apr 19, 2023, 11:30 PM CDT for Jasper County, Poweshiek County, Iowa. It was in force for 30 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
Apr 19, 2023, 11:30 PM CDT (04:30 UTC)
Expired
Apr 20, 2023, 12:00 AM CDT
In force
30 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.0 in

Counties Jasper County, IA, Poweshiek County, IA

The radar

The Des Moines radar (KDMX), 71 km from the middle of the area, began a volume at 04:32 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
Apr 19, 10:58 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 4.5 hours before the alert went out and 199 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 00:00Z on 2023-04-20Temperature 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 00:00Z on 2023-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 149 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
1337 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
149 m²/s²
0-3 km storm-relative helicity
459 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

542 
WFUS53 KDMX 200430
TORDMX
IAC099-157-200500-
/O.NEW.KDMX.TO.W.0013.230420T0430Z-230420T0500Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
1130 PM CDT Wed Apr 19 2023

The National Weather Service in Des Moines  has issued a

* Tornado Warning for...
  Southwestern Poweshiek County in central Iowa...
  Southeastern Jasper County in central Iowa...

* Until midnight CDT.
    
* At 1130 PM CDT, a severe thunderstorm capable of producing a
  tornado was located over Reasnor, or 6 miles south of Newton,
  moving east at 50 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...
  Sully and Kellogg around 1140 PM CDT.
  Lynnville and Oakland Acres around 1145 PM CDT.
  Grinnell, Searsboro and Grinnell Regional Airport around 1150 PM 
  CDT.

This includes Interstate 80 between mile markers 159 and 184.
 
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.

&&

LAT...LON 4152 9267 4151 9299 4151 9315 4169 9318
      4176 9270
TIME...MOT...LOC 0430Z 260DEG 43KT 4161 9303 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.00 IN

$$

KCM
2 follow-up statements
776 
WWUS53 KDMX 200446
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
1146 PM CDT Wed Apr 19 2023

IAC099-157-200500-
/O.CON.KDMX.TO.W.0013.000000T0000Z-230420T0500Z/
Poweshiek IA-Jasper IA-
1146 PM CDT Wed Apr 19 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CDT FOR
SOUTHWESTERN POWESHIEK AND SOUTHEASTERN JASPER COUNTIES...
    
At 1144 PM CDT, a severe thunderstorm capable of producing a tornado
was located near Sully, or 9 miles southwest of Grinnell, moving east
at 45 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...
  Grinnell Regional Airport around 1150 PM CDT.

Other locations in the path of this tornadic thunderstorm include
Searsboro.

This includes Interstate 80 between mile markers 177 and 184.
 
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.

&&

LAT...LON 4151 9291 4167 9291 4173 9270 4152 9267
TIME...MOT...LOC 0444Z 265DEG 39KT 4162 9281 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.00 IN

$$

KCM
688 
WWUS53 KDMX 200454
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
1154 PM CDT Wed Apr 19 2023

IAC099-157-200502-
/O.EXP.KDMX.TO.W.0013.000000T0000Z-230420T0500Z/
Poweshiek IA-Jasper IA-
1154 PM CDT Wed Apr 19 2023

...THE TORNADO WARNING FOR SOUTHWESTERN POWESHIEK AND SOUTHEASTERN
JASPER COUNTIES WILL EXPIRE AT MIDNIGHT CDT...
    
The tornado threat has diminished and the Tornado Warning has been 
cancelled. However, large hail and damaging winds remain possible 
and a Severe Thunderstorm Warning remains in effect for the area.

A Severe Thunderstorm Watch remains in effect until 600 AM CDT for
central Iowa.

Remember, a Severe Thunderstorm Warning still remains in effect for 
eastern Jasper and all of Poweshiek Counties.  

LAT...LON 4151 9291 4167 9291 4173 9270 4152 9267
TIME...MOT...LOC 0452Z 260DEG 43KT 4163 9270 

$$

KCM

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 7:12 PM CDTSevere Thunderstorm Warning Considerable damage threatDMXCrawford, Sac48 min
Apr 19, 7:21 PM CDTTornado WarningDMXCrawford39 min
Apr 19, 7:24 PM CDTSevere Thunderstorm WarningDMXAudubon, Cass51 min
Apr 19, 7:56 PM CDTSevere Thunderstorm Warning Considerable damage threatDMXCrawford, Sac49 min
Apr 19, 8:03 PM CDTTornado WarningDMXCarroll, Crawford, Sac42 min
Apr 19, 8:14 PM CDTSevere Thunderstorm WarningDMXAudubon, Carroll, Greene, Guthrie15 min
Apr 19, 8:17 PM CDTSevere Thunderstorm WarningDMXSac28 min
Apr 19, 8:42 PM CDTSevere Thunderstorm WarningDMXAdair, Dallas, Guthrie, Madison48 min
Apr 19, 9:13 PM CDTSpecial Weather StatementDMXAdams, Decatur32 min
Apr 19, 9:19 PM CDTSevere Thunderstorm WarningDMXBoone, Dallas, Polk26 min
Apr 19, 9:44 PM CDTSevere Thunderstorm WarningDMXBoone, Dallas, Polk, Story46 min
Apr 19, 10:10 PM CDTSevere Thunderstorm WarningDMXBoone, Marshall, Polk, Story50 min
Apr 19, 10:29 PM CDTSevere Thunderstorm WarningDMXJasper, Marshall, Polk, Story46 min
Apr 19, 10:41 PM CDTSevere Thunderstorm WarningDMXMarion, Polk, Warren49 min
Apr 19, 10:57 PM CDTSevere Thunderstorm WarningDMXGrundy, Hardin, Marshall, Story48 min
Apr 19, 11:08 PM CDTSevere Thunderstorm WarningDMXJasper, Marion, Marshall, Polk, Story37 min
Apr 19, 11:41 PM CDTSevere Thunderstorm WarningDMXJasper, Mahaska, Marion, Marshall, Poweshiek, Tama58 min

Nearby

Tornado Warnings in Iowa, 2023Every tornado warning in 2023Tornadoes in 2023

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.