Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 43, NWS Sioux Falls, SD

July 5, 20214 counties in Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 5, 2021, 8:24 PM CDT for 4 counties in Iowa. It was in force for 66 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
Jul 5, 2021, 8:24 PM CDT (01:24 UTC)
Expired
Jul 5, 2021, 9:30 PM CDT
In force
66 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Clay County, IA, Dickinson County, IA, O'Brien County, IA, Osceola County, IA

The radar

The Sioux Falls radar (KFSD), 121 km from the middle of the area, began a volume at 01:28 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

Omaha, NE (KOAX), launched 00:00Z, 1.4 hours before the alert went out and 228 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, Omaha, NE at 00:00Z on 2021-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1088 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, Omaha, NE at 00:00Z on 2021-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
1088 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
1570 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
25 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

931 
WUUS53 KFSD 060124
SVRFSD
IAC041-059-141-143-060230-
/O.NEW.KFSD.SV.W.0043.210706T0124Z-210706T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
824 PM CDT Mon Jul 5 2021

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  Southeastern Osceola County in northwestern Iowa...
  Southern Dickinson County in northwestern Iowa...
  Clay County in northwestern Iowa...
  Northeastern O'Brien County in northwestern Iowa...

* Until 930 PM CDT.

* At 823 PM CDT, a severe thunderstorm was located near Melvin, or 13
  miles southeast of Sibley, moving east at 30 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

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

* This severe thunderstorm will be near...
  Hartley around 830 PM CDT.
  Everly around 845 PM CDT.
  Spencer In Clay County and Fostoria around 900 PM CDT.

Other locations impacted by this severe thunderstorm include Dickens,
Gillett Grove and Moneta.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4315 9562 4344 9553 4337 9491 4296 9492
TIME...MOT...LOC 0123Z 284DEG 28KT 4328 9552 

HAIL...0.75IN
WIND...60MPH
 
$$

JM
2 follow-up statements
644 
WWUS53 KFSD 060158
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
858 PM CDT Mon Jul 5 2021

IAC041-059-141-143-060230-
/O.CON.KFSD.SV.W.0043.000000T0000Z-210706T0230Z/
Osceola IA-Dickinson IA-Clay IA-O'Brien IA-
858 PM CDT Mon Jul 5 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM CDT
FOR SOUTHEASTERN OSCEOLA...SOUTHERN DICKINSON...CLAY AND NORTHEASTERN
O'BRIEN COUNTIES...

At 858 PM CDT, a severe thunderstorm was located over Fostoria, or
near Spencer In Clay County, moving east at 30 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

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

This severe thunderstorm will remain over mainly rural areas of
southeastern Osceola, southern Dickinson, Clay and northeastern
O'Brien Counties, including the following locations... Dickens,
Gillett Grove and Moneta.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4315 9562 4344 9553 4337 9491 4296 9492
TIME...MOT...LOC 0158Z 284DEG 28KT 4321 9515 

HAIL...0.75IN
WIND...60MPH
 
$$

JM
330 
WWUS53 KFSD 060223
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
923 PM CDT Mon Jul 5 2021

IAC041-059-141-143-060233-
/O.EXP.KFSD.SV.W.0043.000000T0000Z-210706T0230Z/
Osceola IA-Dickinson IA-Clay IA-O'Brien IA-
923 PM CDT Mon Jul 5 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN OSCEOLA...
SOUTHERN DICKINSON...CLAY AND NORTHEASTERN O'BRIEN COUNTIES WILL
EXPIRE AT 930 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

LAT...LON 4315 9562 4344 9553 4337 9491 4296 9492
TIME...MOT...LOC 0223Z 284DEG 28KT 4316 9490 

$$

JM

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 5, 7:16 PM CDTSevere Thunderstorm WarningFSDLyon, Osceola44 min
Jul 5, 7:57 PM CDTSevere Thunderstorm WarningFSDLyon, O'Brien, Osceola33 min

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.