Alert archive / Minnesota / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 186, NWS Twin Cities, MN

August 18, 2017Brown County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 18, 2017, 6:37 PM CDT for Brown County, Minnesota. It was in force for 23 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: Aug 18, 2017, 6:37 PM CDT (23:37 UTC)
Expired: Aug 18, 2017, 7:00 PM CDT
In force: 23 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Brown County, MN

The radar

The Minneapolis radar (KMPX), 141 km from the middle of the area, began a volume at 23:38 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
Aug 18, 4:51 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.6 hours before the alert went out and 139 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: 23 J/kg
Mixed-layer CIN: -139 J/kg
Mixed-layer LCL: 1090 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -47 m²/s²
0-3 km storm-relative helicity: -32 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

523 
WUUS53 KMPX 182337
SVRMPX
MNC015-190000-
/O.NEW.KMPX.SV.W.0186.170818T2337Z-170819T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
637 PM CDT FRI AUG 18 2017

The National Weather Service in The Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Southwestern Brown County in south central Minnesota...

* Until 700 PM CDT

* At 637 PM CDT, a severe thunderstorm was located near Sanborn, or
  19 miles north of Windom, moving east at 15 mph.

  HAZARD...60 mph wind gusts and half dollar size hail. 

  SOURCE...Radar indicated. 

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

* This severe thunderstorm will remain over mainly rural areas of
  southwestern Brown County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4420 9510 4420 9499 4411 9503 4411 9510
TIME...MOT...LOC 2337Z 285DEG 12KT 4415 9514 

HAIL...1.25IN
WIND...60MPH
 
$$
AMK

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 3:54 PM CDT	Severe Thunderstorm Warning	MPX	Lac qui Parle	51 min
Aug 18, 4:18 PM CDT	Special Weather Statement	MPX	Lac qui Parle	27 min
Aug 18, 4:44 PM CDT	Severe Thunderstorm Warning	MPX	Lac qui Parle, Yellow Medicine	31 min
Aug 18, 4:55 PM CDT	Special Weather Statement	MPX	Redwood	35 min
Aug 18, 5:07 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Lac qui Parle, Yellow Medicine	38 min
Aug 18, 5:09 PM CDT	Severe Thunderstorm Warning	MPX	Lac qui Parle, Yellow Medicine	25 min
Aug 18, 5:30 PM CDT	Special Weather Statement	MPX	Redwood	30 min
Aug 18, 5:53 PM CDT	Severe Thunderstorm Warning	MPX	Redwood, Renville	37 min
Aug 18, 6:00 PM CDT	Flash Flood Warning	MPX	Redwood, Yellow Medicine	4 hr
Aug 18, 6:15 PM CDT	Severe Thunderstorm Warning	MPX	Redwood	30 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2017 Every severe thunderstorm warning 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.