Alert archive / Minnesota / Tornado Warnings in 2017

Tornado Warning 21, NWS Twin Cities, MN

July 9, 2017Stevens County, Swift County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Jul 9, 2017, 7:57 PM CDT for Stevens County, Swift County, Minnesota. It was in force for 33 min. 2 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
Jul 9, 2017, 7:57 PM CDT (00:57 UTC)
Expired
Jul 9, 2017, 8:30 PM CDT
In force
33 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Tornado
Radar indicated
Hail
1.5 in

Counties Stevens County, MN, Swift County, MN

The radar

The Aberdeen radar (KABR), 180 km from the middle of the area, began a volume at 00:57 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
Jul 9, 8:15 PM CDTHAIL 1.259 Nnw Appleton, MN
Jul 9, 8:17 PM CDTHAIL 1.759 Nnw Appleton, MN

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 9, 7:05 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 1.0 hours before the alert went out and 188 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, Aberdeen, SD at 00:00Z on 2017-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2237 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, Aberdeen, SD at 00:00Z on 2017-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 138 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
2237 J/kg
Mixed-layer CIN
-161 J/kg
Mixed-layer LCL
1841 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
138 m²/s²
0-3 km storm-relative helicity
260 m²/s²
Significant tornado parameter
0.1
Supercell composite
9.3

Open this sounding in Storm Lab

The text

As transmitted.

637 
WFUS53 KMPX 100057
TORMPX
MNC149-151-100145-
/O.NEW.KMPX.TO.W.0021.170710T0057Z-170710T0145Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Twin Cities/Chanhassen MN
757 PM CDT SUN JUL 9 2017

The National Weather Service in The Twin Cities has issued a

* Tornado Warning for...
  Southwestern Stevens County in west central Minnesota...
  Western Swift County in west central Minnesota...

* Until 845 PM CDT
    
* At 756 PM CDT, a severe thunderstorm capable of producing a tornado
  was located over Artichoke, or 15 miles northeast of Ortonville,
  moving east at 30 mph.

  HAZARD...Tornado and ping pong ball 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...
  Lake Oliver around 810 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Danvers and Holloway.

This includes the following highways...
 U.S. Highway 12 between mile markers 23 and 34.
 U.S. Highway 59 between mile markers 143 and 154.

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 4547 9623 4541 9574 4519 9577 4533 9612
      4541 9612 4541 9622 4542 9624 4544 9625
TIME...MOT...LOC 0056Z 285DEG 28KT 4539 9615 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

jrb
2 follow-up statements
611 
WWUS53 KMPX 100111
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
811 PM CDT SUN JUL 9 2017

MNC149-100121-
/O.CAN.KMPX.TO.W.0021.000000T0000Z-170710T0145Z/
Stevens MN-
811 PM CDT SUN JUL 9 2017

...THE TORNADO WARNING FOR SOUTHWESTERN STEVENS COUNTY IS
CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

A tornado watch remains in effect until 100 AM CDT for west central
Minnesota.

LAT...LON 4519 9577 4533 9612 4541 9612 4534 9575
TIME...MOT...LOC 0111Z 292DEG 22KT 4535 9607 

$$

MNC151-100145-
/O.CON.KMPX.TO.W.0021.000000T0000Z-170710T0145Z/
Swift MN-
811 PM CDT SUN JUL 9 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 PM CDT FOR WESTERN
SWIFT COUNTY...
    
At 811 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Lake Oliver, or 18 miles east of Ortonville, moving
southeast at 25 mph.

HAZARD...Tornado and ping pong ball 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...
  Lake Oliver around 815 PM CDT. 

Other locations impacted by this tornadic thunderstorm include
Danvers and Holloway.

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 4519 9577 4533 9612 4541 9612 4534 9575
TIME...MOT...LOC 0111Z 292DEG 22KT 4535 9607 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

jrb
862 
WWUS53 KMPX 100130
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
830 PM CDT SUN JUL 9 2017

MNC151-100139-
/O.CAN.KMPX.TO.W.0021.000000T0000Z-170710T0145Z/
Swift MN-
830 PM CDT SUN JUL 9 2017

...THE TORNADO 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 tornado watch remains in effect until 100 AM CDT for west central
Minnesota.

LAT...LON 4519 9577 4533 9612 4541 9612 4534 9575
TIME...MOT...LOC 0128Z 285DEG 28KT 4549 9681 

$$

jrb

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 7:35 PM CDTSevere Thunderstorm WarningMPXStevens, Swift40 min
Jul 9, 7:50 PM CDTSevere Thunderstorm WarningMPXMille Lacs, Morrison40 min
Jul 9, 7:51 PM CDTSevere Thunderstorm WarningMPXMcLeod, Meeker, Renville39 min
Jul 9, 8:09 PM CDTTornado WarningMPXSwift28 min
Jul 9, 8:21 PM CDTTornado WarningMPXChippewa, Lac qui Parle39 min
Jul 9, 8:22 PM CDTSevere Thunderstorm WarningMPXBenton, Morrison38 min
Jul 9, 8:25 PM CDTSevere Thunderstorm WarningMPXKanabec, Mille Lacs40 min
Jul 9, 8:28 PM CDTSpecial Weather StatementMPXMcLeod, Scott47 min
Jul 9, 8:33 PM CDTSevere Thunderstorm WarningMPXMcLeod, Renville, Sibley42 min
Jul 9, 8:54 PM CDTSevere Thunderstorm WarningMPXChippewa, Lac qui Parle, Yellow Medicine66 min
Jul 9, 8:55 PM CDTSevere Thunderstorm WarningMPXBenton, Sherburne25 min
Jul 9, 8:56 PM CDTSevere Thunderstorm WarningMPXDakota, Le Sueur, Rice, Scott34 min
Jul 9, 8:58 PM CDTSevere Thunderstorm WarningMPXChippewa, Swift47 min
Jul 9, 9:03 PM CDTSevere Thunderstorm WarningMPXNicollet, Sibley42 min
Jul 9, 9:06 PM CDTSevere Thunderstorm WarningMPXKandiyohi, Pope, Stearns27 min
Jul 9, 9:09 PM CDTSevere Thunderstorm WarningMPXChippewa, Lac qui Parle, Swift20 min
Jul 9, 9:11 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Le Sueur, Nicollet, Waseca49 min
Jul 9, 9:16 PM CDTSevere Thunderstorm WarningMPXDakota, Hennepin, Ramsey, Washington44 min
Jul 9, 9:23 PM CDTSevere Thunderstorm WarningMPXDakota, Rice, Scott53 min
Jul 9, 9:26 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Brown, Nicollet49 min
Jul 9, 9:30 PM CDTTornado WarningMPXNicollet30 min
Jul 9, 9:51 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Steele, Waseca54 min
Jul 9, 10:10 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Nicollet35 min
Jul 9, 10:19 PM CDTTornado WarningMPXBlue Earth41 min
Jul 9, 10:34 PM CDTSevere Thunderstorm WarningMPXNicollet, Sibley41 min
Jul 9, 10:41 PM CDTSevere Thunderstorm WarningMPXFaribault, Freeborn, Steele, Waseca64 min
Jul 9, 10:51 PM CDTSevere Thunderstorm WarningMPXMcLeod, Renville, Sibley39 min
Jul 9, 10:55 PM CDTSevere Thunderstorm WarningMPXBrown, Redwood, Renville35 min
Jul 9, 11:05 PM CDTSevere Thunderstorm WarningMPXBlue Earth40 min
Jul 9, 11:17 PM CDTSevere Thunderstorm WarningMPXFaribault, Freeborn43 min
Jul 9, 11:39 PM CDTSevere Thunderstorm WarningMPXBlue Earth, Brown, Nicollet, Watonwan37 min
Jul 9, 11:55 PM CDTSevere Thunderstorm WarningMPXRedwood18 min
Jul 10, 12:05 AM CDTSevere Thunderstorm WarningMPXBlue Earth, Faribault, Martin40 min
Jul 10, 12:45 AM CDTSevere Thunderstorm WarningMPXFaribault, Freeborn30 min
Jul 10, 12:47 AM CDTSevere Thunderstorm WarningMPXNicollet26 min
Jul 10, 1:30 AM CDTSevere Thunderstorm WarningMPXBlue Earth, Brown, Watonwan35 min

Nearby

Tornado Warnings in Minnesota, 2017Every tornado warning in 2017Tornadoes in 2017

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.