Alert archive / Minnesota / Tornado Warnings in 2018

Tornado Warning 8, NWS Twin Cities, MN

September 4, 2018Steele County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Sep 4, 2018, 3:29 PM CDT for Steele County, Minnesota. It was in force for 31 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: Sep 4, 2018, 3:29 PM CDT (20:29 UTC)
Expired: Sep 4, 2018, 4:00 PM CDT
In force: 31 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Steele County, MN

The radar

The Minneapolis radar (KMPX), 100 km from the middle of the area, began a volume at 20:28 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

Minneapolis, MN (KMPX), launched 12:00Z, 8.5 hours before the alert went out and 101 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 106 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 667 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 71 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

956 
WFUS53 KMPX 042029
TORMPX
MNC147-042100-
/O.NEW.KMPX.TO.W.0008.180904T2029Z-180904T2100Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Twin Cities/Chanhassen MN
329 PM CDT TUE SEP 4 2018

The National Weather Service in The Twin Cities has issued a

* Tornado Warning for...
  East central Steele County in south central Minnesota...

* Until 400 PM CDT.
    
* At 329 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Steele Center, or 7 miles southeast of Owatonna,
  moving northeast at 20 mph.

  HAZARD...Tornado.

  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 tornadic thunderstorm will remain over mainly rural areas of
  east central Steele County.

This includes U.S. Highway 14 between mile markers 179 and 182.
 
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 4400 9319 4411 9305 4399 9305 4395 9315
TIME...MOT...LOC 2029Z 220DEG 18KT 4400 9314 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

ETA

1 follow-up statement

194 
WWUS53 KMPX 042051
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
351 PM CDT TUE SEP 4 2018

MNC147-042100-
/O.EXP.KMPX.TO.W.0008.000000T0000Z-180904T2100Z/
Steele MN-
351 PM CDT TUE SEP 4 2018

...THE TORNADO WARNING FOR EAST CENTRAL STEELE COUNTY WILL EXPIRE AT
400 PM CDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 1000 PM CDT for south central
Minnesota.

LAT...LON 4400 9319 4411 9305 4399 9305 4395 9315
TIME...MOT...LOC 2050Z 220DEG 18KT 4408 9305 

$$

ETA

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 4, 3:15 AM CDT	Flash Flood Watch	MPX	Blue Earth, Brown, Dakota, Faribault, Freeborn, Goodhue and 7 more	25 hr
Sep 4, 2:15 PM CDT	Special Weather Statement	MPX	Freeborn	30 min
Sep 4, 5:55 PM CDT	Severe Thunderstorm Warning	MPX	Freeborn	65 min
Sep 4, 6:10 PM CDT	Tornado Warning	MPX	Freeborn	35 min

Nearby

Tornado Warnings in Minnesota, 2018 Every tornado warning in 2018 Tornadoes in 2018

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.