Alert archive / Minnesota / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 170, NWS Twin Cities, MN

July 19, 2017Freeborn County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 19, 2017, 4:40 PM CDT for Freeborn County, Minnesota. It was in force for 20 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: Jul 19, 2017, 4:40 PM CDT (21:40 UTC)
Expired: Jul 19, 2017, 5:00 PM CDT
In force: 20 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Freeborn County, MN

The radar

The Minneapolis radar (KMPX), 142 km from the middle of the area, began a volume at 21:42 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
Jul 19, 12:36 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 9.7 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1964 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: -10 m²/s²
0-3 km storm-relative helicity: 91 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

061 
WUUS53 KMPX 192140
SVRMPX
MNC047-192200-
/O.NEW.KMPX.SV.W.0170.170719T2140Z-170719T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
440 PM CDT WED JUL 19 2017

The National Weather Service in The Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Southeastern Freeborn County in south central Minnesota...

* Until 500 PM CDT

* At 440 PM CDT, severe thunderstorms were located along a line
  extending from I 90 Exit 175 to Myrtle to near Kensett, moving east
  at 45 mph.

  HAZARD...60 mph wind gusts and penny size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to roofs, siding, and trees. 

* These severe thunderstorms will remain over mainly rural areas of
  southeastern Freeborn County, including the following locations:
  Myrtle.

This includes Interstate 90 between mile markers 170 and 173.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4377 9306 4353 9305 4350 9305 4350 9324
TIME...MOT...LOC 2140Z 290DEG 41KT 4367 9303 4354 9316 4338 9322 

HAIL...0.75IN
WIND...60MPH
 
$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 19, 2:06 PM CDT	Severe Thunderstorm Warning	MPX	Redwood	39 min
Jul 19, 2:38 PM CDT	Severe Thunderstorm Warning	MPX	Brown, Watonwan	52 min
Jul 19, 2:51 PM CDT	Tornado Warning	MPX	Brown	24 min
Jul 19, 3:11 PM CDT	Severe Thunderstorm Warning	MPX	Blue Earth, Brown, Nicollet, Watonwan	34 min
Jul 19, 3:38 PM CDT	Severe Thunderstorm Warning	MPX	Blue Earth, Le Sueur, Rice, Waseca	37 min
Jul 19, 3:50 PM CDT	Severe Thunderstorm Warning	MPX	Faribault, Martin	40 min
Jul 19, 3:57 PM CDT	Severe Thunderstorm Warning	MPX	Faribault, Freeborn	18 min
Jul 19, 4:02 PM CDT	Severe Thunderstorm Warning	MPX	Dakota, Goodhue	43 min
Jul 19, 4:06 PM CDT	Severe Thunderstorm Warning	MPX	Faribault, Freeborn, Steele, Waseca	39 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.