Alert archive / Minnesota / Tornado Warnings in 2018

Tornado Warning 9, NWS Twin Cities, MN

September 4, 2018Freeborn County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Sep 4, 2018, 6:10 PM CDT for Freeborn County, Minnesota. It was in force for 35 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, 6:10 PM CDT (23:10 UTC)
Expired: Sep 4, 2018, 6:45 PM CDT
In force: 35 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Freeborn County, MN

The radar

The Minneapolis radar (KMPX), 142 km from the middle of the area, began a volume at 23:10 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 watch it was issued in

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

Issued	Product	Office	Lasted
Sep 4, 3:35 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.2 hours before the alert went out and 143 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.

656 
WFUS53 KMPX 042310
TORMPX
MNC047-042345-
/O.NEW.KMPX.TO.W.0009.180904T2310Z-180904T2345Z/

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

The National Weather Service in The Twin Cities has issued a

* Tornado Warning for...
  Southeastern Freeborn County in south central Minnesota...

* Until 645 PM CDT.
    
* At 610 PM CDT, a severe thunderstorm capable of producing a tornado
  was located near Glenville, or 7 miles northwest of Northwood,
  moving northeast at 30 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 dangerous storm will be near...
  Glenville around 615 PM CDT.
  Hayward around 630 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Myrtle.

This includes the following highways...
 Interstate 35 between mile markers 1 and 4.
 Interstate 90 between mile markers 162 and 173.

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 4368 9328 4366 9307 4350 9323 4350 9340
      4351 9340
TIME...MOT...LOC 2310Z 207DEG 24KT 4353 9330 

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

$$

ETA

1 follow-up statement

408 
WWUS53 KMPX 042339
SVSMPX

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

MNC047-042345-
/O.CON.KMPX.TO.W.0009.000000T0000Z-180904T2345Z/
Freeborn MN-
639 PM CDT TUE SEP 4 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR
SOUTHEASTERN FREEBORN COUNTY...
    
At 638 PM CDT, a confirmed tornado was located nortwest of Myrtle, 
or 8 miles southeast of Albert Lea, moving northeast at 20 mph.

HAZARD...Damaging tornado.

SOURCE...Emergency management confirmed tornado.

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
southeastern Freeborn County, including the following locations...
Myrtle.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. 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 4353 9320 4357 9330 4368 9325 4366 9307
TIME...MOT...LOC 2338Z 228DEG 18KT 4359 9322 

TORNADO...OBSERVED
HAIL...<.75IN

$$

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, 3:29 PM CDT	Tornado Warning	MPX	Steele	31 min
Sep 4, 5:55 PM CDT	Severe Thunderstorm Warning	MPX	Freeborn	65 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.