Alert archive / Minnesota / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 154, NWS Twin Cities, MN

August 24, 2020Swift County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 24, 2020, 2:21 AM CDT for Swift County, Minnesota. It was in force for 43 min. 3 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
Aug 24, 2020, 2:21 AM CDT (07:21 UTC)
Expired
Aug 24, 2020, 3:04 AM CDT
In force
43 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.5 in
Wind
60.0 mph

County Swift County, MN

The radar

The Minneapolis radar (KMPX), 190 km from the middle of the area, began a volume at 07:25 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
Aug 24, 2:40 AM CDTTSTM WND GST 792 Wnw Benson, MNMEASURED AT KBBB.
Aug 24, 2:50 AM CDTTSTM WND DMGBenson, MNTREES OF VARIOUS SIZE AND POWER LINES DOWN.
Aug 24, 2:50 AM CDTTSTM WND GST 842 Wnw Benson, MNCORRECTS PREVIOUS TSTM WND GST REPORT FROM 2 WNW BENSON. MEASURED AT KBBB.

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, 7.4 hours before the alert went out and 187 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 2020-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 669 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, Minneapolis, MN at 00:00Z on 2020-08-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 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
669 J/kg
Mixed-layer CIN
-226 J/kg
Mixed-layer LCL
1807 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

811 
WUUS53 KMPX 240721
SVRMPX
MNC151-240815-
/O.NEW.KMPX.SV.W.0154.200824T0721Z-200824T0815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
221 AM CDT Mon Aug 24 2020

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Western Swift County in west central Minnesota...

* Until 315 AM CDT.

* At 220 AM CDT, a severe thunderstorm was located over Artichoke, or
  15 miles northeast of Ortonville, moving southeast at 35 mph.

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

  SOURCE...Radar indicated.

  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 thunderstorm will be near...
  Lake Oliver around 235 AM CDT.
  Benson around 310 AM CDT.

Other locations impacted by this severe thunderstorm include 
Danvers, Hagen, Appleton Airport, Clontarf and Holloway.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4527 9611 4541 9611 4541 9578 4535 9553
      4515 9566 4515 9581 4524 9612
TIME...MOT...LOC 0720Z 294DEG 29KT 4540 9615 

HAIL...1.50IN
WIND...60MPH
 
$$
2 follow-up statements
210 
WWUS53 KMPX 240745
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
245 AM CDT Mon Aug 24 2020

MNC151-240815-
/O.CON.KMPX.SV.W.0154.000000T0000Z-200824T0815Z/
Swift MN-
245 AM CDT Mon Aug 24 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 AM CDT
FOR WESTERN SWIFT COUNTY...

At 244 AM CDT, a severe thunderstorm was located near Lake Oliver, or
18 miles south of Morris, moving southeast at 35 mph.

This is a very dangerous storm.

HAZARD...80 mph wind gusts and quarter size hail.

SOURCE...Radar indicated. At 740 AM, a 79 mph wind gust was reported 
         in Benson.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be heavily damaged. Expect 
         considerable damage to roofs, windows, and vehicles. 
         Extensive tree damage and power outages are likely.

This severe storm will be near...
  Benson around 310 AM CDT.

Other locations impacted by this severe thunderstorm include 
Danvers, Hagen, Clontarf and Holloway.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4520 9599 4541 9588 4541 9578 4535 9553
      4515 9566 4515 9581
TIME...MOT...LOC 0744Z 294DEG 29KT 4532 9589 

HAIL...1.00IN
WIND...80MPH
 
$$
415 
WWUS53 KMPX 240804
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
304 AM CDT Mon Aug 24 2020

MNC151-240813-
/O.CAN.KMPX.SV.W.0154.000000T0000Z-200824T0815Z/
Swift MN-
304 AM CDT Mon Aug 24 2020

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN SWIFT COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled. A severe thunderstorm 
warning remains in effect until 330 am for eastern Swift county

LAT...LON 4520 9599 4541 9588 4541 9578 4535 9553
      4515 9566 4515 9581
TIME...MOT...LOC 0802Z 294DEG 29KT 4526 9569 

$$

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 24, 1:39 AM CDTSpecial Weather StatementMPXStevens66 min
Aug 24, 1:58 AM CDTSevere Thunderstorm WarningMPXStevens46 min
Aug 24, 2:30 AM CDTSevere Thunderstorm WarningMPXPope, Stevens, Swift35 min
Aug 24, 2:41 AM CDTSevere Thunderstorm WarningMPXChippewa, Kandiyohi, Pope, Swift49 min
Aug 24, 3:13 AM CDTSevere Thunderstorm WarningMPXKandiyohi, Meeker, Renville62 min
Aug 24, 3:40 AM CDTHeat AdvisoryMPXAnoka, Blue Earth, Brown, Carver, Chippewa, Dakota and 20 more16 hr
Aug 24, 3:52 AM CDTSevere Thunderstorm WarningMPXMcLeod, Meeker, Wright38 min
Aug 24, 5:31 AM CDTSpecial Weather StatementMPXSwift44 min
Aug 24, 6:10 AM CDTSpecial Weather StatementMPXChippewa50 min
Aug 24, 6:43 AM CDTSpecial Weather StatementMPXRenville47 min
Aug 24, 7:30 AM CDTSpecial Weather StatementMPXNicollet, Sibley60 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 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.