Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 102, NWS Des Moines, IA

August 26, 2021Emmet County, Palo Alto County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 26, 2021, 10:30 PM CDT for Emmet County, Palo Alto County, Iowa. It was in force for 45 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
Aug 26, 2021, 10:30 PM CDT (03:30 UTC)
Expired
Aug 26, 2021, 11:15 PM CDT
In force
45 min
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Emmet County, IA, Palo Alto County, IA

The radar

The Sioux Falls radar (KFSD), 174 km from the middle of the area, began a volume at 03:30 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

Minneapolis, MN (KMPX), launched 00:00Z, 3.5 hours before the alert went out and 186 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, Minneapolis, MN at 00:00Z on 2021-08-27Temperature 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, Minneapolis, MN at 00:00Z on 2021-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 393 square meters per square second.19395878Sfc1 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
792 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
393 m²/s²
0-3 km storm-relative helicity
392 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

812 
WUUS53 KDMX 270330
SVRDMX
IAC063-147-270415-
/O.NEW.KDMX.SV.W.0102.210827T0330Z-210827T0415Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Des Moines IA
1030 PM CDT Thu Aug 26 2021

The National Weather Service in Des Moines  has issued a

* Severe Thunderstorm Warning for...
  Southeastern Emmet County in northwestern Iowa...
  Northern Palo Alto County in northwestern Iowa...

* Until 1115 PM CDT.

* At 1030 PM CDT, a severe thunderstorm was located near High Lake,
  or 9 miles northwest of Emmetsburg, moving northeast at 20 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...
  Five Island Lake around 1040 PM CDT.
  High Lake around 1045 PM CDT.
  Ingham Lake around 1050 PM CDT.

Other locations in the path of this severe thunderstorm include Swan
Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4345 9444 4320 9445 4312 9491 4331 9491
      4349 9445
TIME...MOT...LOC 0330Z 244DEG 18KT 4324 9477 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Krull
2 follow-up statements
117 
WWUS53 KDMX 270349
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
1049 PM CDT Thu Aug 26 2021

IAC063-147-270415-
/O.CON.KDMX.SV.W.0102.000000T0000Z-210827T0415Z/
Emmet IA-Palo Alto IA-
1049 PM CDT Thu Aug 26 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR SOUTHEASTERN EMMET AND NORTHERN PALO ALTO COUNTIES...

At 1049 PM CDT, a severe thunderstorm was located near High Lake, or
9 miles north of Emmetsburg, moving east at 20 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
southeastern Emmet and northern Palo Alto Counties, including the
following locations... Armstrong, Wolden County Park, Ringsted,
Graettinger, Wallingford, Lost Island Lake State Park and Gruver.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4345 9444 4320 9445 4314 9481 4317 9491
      4331 9491 4349 9445
TIME...MOT...LOC 0349Z 252DEG 16KT 4325 9468 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Krull
524 
WWUS53 KDMX 270414
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
1114 PM CDT Thu Aug 26 2021

IAC063-147-270424-
/O.EXP.KDMX.SV.W.0102.000000T0000Z-210827T0415Z/
Emmet IA-Palo Alto IA-
1114 PM CDT Thu Aug 26 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN EMMET AND
NORTHERN PALO ALTO COUNTIES WILL EXPIRE AT 1115 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.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 4345 9444 4320 9445 4314 9481 4317 9491
      4331 9491 4349 9445
TIME...MOT...LOC 0414Z 244DEG 18KT 4330 9453 

$$

Krull

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 26, 7:02 PM CDTSevere Thunderstorm WarningDMXAudubon, Carroll28 min
Aug 26, 8:35 PM CDTSpecial Weather StatementDMXPoweshiek40 min
Aug 26, 8:47 PM CDTSevere Thunderstorm WarningDMXMahaska, Poweshiek58 min
Aug 26, 9:46 PM CDTSpecial Weather StatementDMXMahaska44 min
Aug 26, 10:26 PM CDTSpecial Weather StatementDMXMahaska34 min
Aug 26, 10:52 PM CDTSpecial Weather StatementDMXWapello38 min
Aug 26, 11:42 PM CDTSevere Thunderstorm WarningDMXEmmet, Palo Alto33 min
Aug 27, 12:13 AM CDTSpecial Weather StatementDMXEmmet32 min
Aug 27, 2:08 PM CDTSpecial Weather StatementDMXHancock37 min
Aug 27, 2:59 PM CDTSpecial Weather StatementDMXCerro Gordo16 min
Aug 27, 4:23 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Hancock52 min
Aug 27, 4:48 PM CDTTornado WarningDMXCerro Gordo, Hancock57 min
Aug 27, 4:58 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Franklin, Hancock32 min
Aug 27, 5:23 PM CDTTornado Warning Tornado observedDMXCerro Gordo37 min
Aug 27, 5:25 PM CDTTornado WarningDMXCerro Gordo35 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.