Alert archive / Iowa / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 13, NWS Sioux Falls, SD

June 4, 20204 counties in Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 4, 2020, 11:20 PM CDT for 4 counties in Iowa. It was in force for 40 min. 7 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 4, 2020, 11:20 PM CDT (04:20 UTC)
Expired
Jun 5, 2020, 12:00 AM CDT
In force
40 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.0 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), 119 km from the middle of the area, began a volume at 04:22 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 4, 11:20 PM CDTHAIL 1Sanborn, IAREPORT VIA SOCIAL MEDIA.
Jun 4, 11:27 PM CDTHAIL 1.75Hartley, IAPHOTO OF GOLF BALL SIZED HAIL REPORTED VIA SOCIAL MEDIA.
Jun 4, 11:51 PM CDTHAIL 1.751 S Milford, IAQUARTER TO GOLF BALL SIZED HAIL REPORTED NEAR MILFORD.
Jun 4, 11:52 PM CDTTSTM WND DMG3 Nnw Orleans, IA2.5 FT DIAMETER TREE BLOCKING MOST OF COUNTY RD M49 ON NORTHWEST SIDE OF BIG SPIRIT LAKE.
Jun 4, 11:52 PM CDTHAIL 1Milford, IAREPORT VIA SOCIAL MEDIA.
Jun 4, 11:55 PM CDTTSTM WND DMG4 Nw Terril, IAA ROUGHLY 2 FOOT DIAMETER TREE TRUNK BROKEN.
Jun 4, 11:57 PM CDTTSTM WND DMG4 Se Arnolds Park, IACROP DAMAGE 3-4 MILES EAST OF MILFORD.

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 4.3 hours before the alert went out and 226 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 2020-06-05Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2020-06-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 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
2762 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

365 
WUUS53 KFSD 050420
SVRFSD
IAC041-059-141-143-050500-
/O.NEW.KFSD.SV.W.0013.200605T0420Z-200605T0500Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
1120 PM CDT Thu Jun 4 2020

The National Weather Service in Sioux Falls has issued a

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

* Until midnight CDT.

* At 1120 PM CDT, a severe thunderstorm was located near Hartley, or
  14 miles east of Sheldon, moving east at 50 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...
  Hartley around 1125 PM CDT.
  Everly around 1135 PM CDT.
  Spencer In Clay County and Fostoria around 1145 PM CDT.
  Milford, Arnolds Park and West Okoboji around 1150 PM CDT.
  Terril around 1200 AM CDT.

Other locations impacted by this severe thunderstorm include Moneta.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4304 9564 4321 9572 4350 9513 4350 9491
      4318 9492
TIME...MOT...LOC 0420Z 252DEG 43KT 4316 9556 

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

BT
3 follow-up statements
704 
WWUS53 KFSD 050428
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1128 PM CDT Thu Jun 4 2020

IAC041-059-141-143-050500-
/O.CON.KFSD.SV.W.0013.000000T0000Z-200605T0500Z/
Osceola IA-Dickinson IA-Clay IA-O'Brien IA-
1128 PM CDT Thu Jun 4 2020

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

At 1128 PM CDT, a severe thunderstorm was located over Hartley, or 14
miles west of Spencer In Clay County, moving east at 50 mph.

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

SOURCE...Trained weather spotters reported quarter sized hail with 
         this storm in Sanborn.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe storm will be near...
  Spencer In Clay County and Fostoria around 1145 PM CDT.
  Milford, Arnolds Park and West Okoboji around 1150 PM CDT.
  Terril around 1200 AM CDT.

Other locations impacted by this severe thunderstorm include Moneta.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4304 9564 4321 9572 4350 9513 4350 9491
      4318 9492
TIME...MOT...LOC 0428Z 252DEG 43KT 4319 9543 

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

BT
024 
WWUS53 KFSD 050432
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1132 PM CDT Thu Jun 4 2020

IAC041-059-141-143-050500-
/O.CON.KFSD.SV.W.0013.000000T0000Z-200605T0500Z/
Osceola IA-Dickinson IA-Clay IA-O'Brien IA-
1132 PM CDT Thu Jun 4 2020

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

At 1132 PM CDT, a severe thunderstorm was located near Everly, or 11
miles west of Spencer In Clay County, moving east at 50 mph.

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

SOURCE...Trained weather spotters.

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.

This severe storm will be near...
  Spencer In Clay County and Fostoria around 1145 PM CDT.
  Milford, Arnolds Park and West Okoboji around 1150 PM CDT.
  Terril around 1200 AM CDT.

Other locations impacted by this severe thunderstorm include Moneta.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4304 9564 4321 9572 4350 9513 4350 9491
      4318 9492
TIME...MOT...LOC 0432Z 252DEG 43KT 4321 9536 

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

BT
354 
WWUS53 KFSD 050445
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
1145 PM CDT Thu Jun 4 2020

IAC141-050454-
/O.CAN.KFSD.SV.W.0013.000000T0000Z-200605T0500Z/
O'Brien IA-
1145 PM CDT Thu Jun 4 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN O'BRIEN COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4311 9531 4322 9539 4325 9539 4326 9541
      4333 9547 4350 9513 4350 9491 4318 9492
TIME...MOT...LOC 0444Z 248DEG 43KT 4325 9522 

$$

IAC041-059-143-050500-
/O.CON.KFSD.SV.W.0013.000000T0000Z-200605T0500Z/
Osceola IA-Dickinson IA-Clay IA-
1145 PM CDT Thu Jun 4 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT CDT
FOR SOUTHEASTERN OSCEOLA...DICKINSON AND NORTHERN CLAY COUNTIES...

At 1144 PM CDT, a severe thunderstorm was located near Fostoria, or 8
miles northwest of Spencer In Clay County, moving east at 50 mph.

HAZARD...Golf ball size hail and 60 mph wind gusts.

SOURCE...Trained weather spotters. At approximately 1140 PM, golf 
         ball sized hail was reported 4 miles east of Hartley.

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.

This severe storm will be near...
  Milford around 1150 PM CDT.
  Arnolds Park around 1155 PM CDT.
  Terril around 1200 AM CDT.
  Superior around 1205 AM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4311 9531 4322 9539 4325 9539 4326 9541
      4333 9547 4350 9513 4350 9491 4318 9492
TIME...MOT...LOC 0444Z 248DEG 43KT 4325 9522 

HAIL...1.75IN
WIND...60MPH
 
$$

SG

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 4, 11:16 PM CDTSevere Thunderstorm WarningFSDDickinson, Osceola44 min
Jun 4, 11:37 PM CDTSevere Thunderstorm WarningFSDCherokee38 min
Jun 4, 11:50 PM CDTSevere Thunderstorm WarningFSDClay, Dickinson40 min
Jun 5, 12:08 AM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee52 min
Jun 5, 12:15 AM CDTSevere Thunderstorm WarningFSDClay, Dickinson, O'Brien, Osceola45 min
Jun 5, 12:56 AM CDTSevere Thunderstorm WarningFSDBuena Vista34 min
Jun 5, 1:20 AM CDTSevere Thunderstorm WarningFSDBuena Vista, Clay40 min
Jun 5, 1:27 AM CDTSevere Thunderstorm WarningFSDIda48 min
Jun 5, 1:38 AM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee, Clay, O'Brien37 min
Jun 5, 1:51 AM CDTSevere Thunderstorm WarningFSDBuena Vista, Cherokee54 min
Jun 5, 2:11 AM CDTSevere Thunderstorm WarningFSDIda21 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2020Every severe thunderstorm warning in 2020

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.