Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 123, NWS Twin Cities, MN

September 16, 2021Mille Lacs County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Sep 16, 2021, 7:53 PM CDT for Mille Lacs County, Minnesota. It was in force for 37 min. 3 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: Sep 16, 2021, 7:53 PM CDT (00:53 UTC)
Expired: Sep 16, 2021, 8:30 PM CDT
In force: 37 min
Issued by: NWS Twin Cities, MN
Area: Storm-based polygon
Hail: 1.25 in
Wind: 60.0 mph

County Mille Lacs County, MN

The radar

The Duluth radar (KDLH), 133 km from the middle of the area, began a volume at 00:53 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

Time	Report	Where
Sep 16, 8:10 PM CDT	HAIL 0.25	Onamia, MN
Sep 16, 8:10 PM CDT	HAIL 1	Wahkon, MN
Sep 16, 8:25 PM CDT	HAIL 1	1 Nnw Isle, 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.

Issued	Product	Office	Lasted
Sep 16, 5:57 PM CDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 0.9 hours before the alert went out and 271 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: 832 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: -33 m²/s²
0-3 km storm-relative helicity: 175 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

450 
WUUS53 KMPX 170053
SVRMPX
MNC095-170130-
/O.NEW.KMPX.SV.W.0123.210917T0053Z-210917T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Twin Cities/Chanhassen MN
753 PM CDT Thu Sep 16 2021

The National Weather Service in the Twin Cities has issued a

* Severe Thunderstorm Warning for...
  Northern Mille Lacs County in east central Minnesota...

* Until 830 PM CDT.

* At 753 PM CDT, a severe thunderstorm was located over Onamia, or 14
  miles south of Mille Lacs Lake, moving northeast at 45 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 be near...
  Isle and Wahkon around 805 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until midnight CDT for east central
Minnesota.

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

A Tornado Watch remains in effect until midnight CDT for east central
Minnesota.

&&

LAT...LON 4612 9343 4602 9376 4606 9381 4618 9381
      4625 9367 4624 9343
TIME...MOT...LOC 0053Z 238DEG 40KT 4610 9370 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BPH

2 follow-up statements

874 
WWUS53 KMPX 170114
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
814 PM CDT Thu Sep 16 2021

MNC095-170130-
/O.CON.KMPX.SV.W.0123.000000T0000Z-210917T0130Z/
Mille Lacs MN-
814 PM CDT Thu Sep 16 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR NORTHEASTERN MILLE LACS COUNTY...

At 813 PM CDT, a severe thunderstorm was located near Isle, or 13 
miles southeast of Mille Lacs Lake, moving northeast at 40 mph. A 
trained spotter reported quarter sized hail in northern Mille Lacs 
county.

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

SOURCE...Trained weather spotters.

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
northeastern Mille Lacs County, including the following locations...
Bayview and Lake Mille Lacs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until midnight CDT for east central
Minnesota.

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

&&

LAT...LON 4612 9343 4605 9369 4615 9375 4625 9360
      4624 9343
TIME...MOT...LOC 0113Z 237DEG 37KT 4619 9349 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BPH

324 
WWUS53 KMPX 170128
SVSMPX

Severe Weather Statement
National Weather Service Twin Cities/Chanhassen MN
828 PM CDT Thu Sep 16 2021

MNC095-170138-
/O.EXP.KMPX.SV.W.0123.000000T0000Z-210917T0130Z/
Mille Lacs MN-
828 PM CDT Thu Sep 16 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MILLE LACS COUNTY
WILL EXPIRE AT 830 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 midnight CDT for east central
Minnesota.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
the Twin Cities.

LAT...LON 4612 9343 4605 9369 4615 9375 4625 9360
      4624 9343
TIME...MOT...LOC 0128Z 238DEG 40KT 4627 9331 

$$

Borghoff

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 16, 7:07 PM CDT	Tornado Warning	MPX	Mille Lacs, Morrison	23 min
Sep 16, 7:08 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Kandiyohi	37 min
Sep 16, 7:14 PM CDT	Special Weather Statement	MPX	Chippewa	31 min
Sep 16, 7:18 PM CDT	Severe Thunderstorm Warning	MPX	Chippewa, Kandiyohi, Renville	27 min
Sep 16, 7:30 PM CDT	Severe Thunderstorm Warning	MPX	Kanabec, Mille Lacs, Morrison	45 min
Sep 16, 7:43 PM CDT	Special Weather Statement	MPX	Mille Lacs	47 min
Sep 16, 7:44 PM CDT	Severe Thunderstorm Warning Considerable damage threat	MPX	Kandiyohi, Renville	31 min
Sep 16, 7:47 PM CDT	Special Weather Statement	MPX	Meeker	28 min
Sep 16, 8:12 PM CDT	Severe Thunderstorm Warning	MPX	Kandiyohi, McLeod, Meeker, Renville	33 min
Sep 16, 8:38 PM CDT	Special Weather Statement	MPX	Isanti	37 min
Sep 16, 8:45 PM CDT	Severe Thunderstorm Warning	MPX	McLeod, Meeker, Wright	30 min
Sep 16, 9:12 PM CDT	Special Weather Statement	MPX	Hennepin	33 min
Sep 16, 10:24 PM CDT	Special Weather Statement	MPX	Lac qui Parle	36 min
Sep 16, 10:37 PM CDT	Special Weather Statement	MPX	Kanabec	23 min
Sep 16, 11:06 PM CDT	Special Weather Statement	MPX	Stearns	24 min
Sep 17, 12:09 AM CDT	Special Weather Statement	MPX	Mille Lacs	36 min
Sep 17, 12:21 AM CDT	Special Weather Statement	MPX	Benton	24 min
Sep 17, 12:47 AM CDT	Special Weather Statement	MPX	Mille Lacs	28 min
Sep 17, 12:55 AM CDT	Special Weather Statement	MPX	Redwood, Yellow Medicine	35 min
Sep 17, 1:10 AM CDT	Special Weather Statement	MPX	Kanabec	20 min
Sep 17, 1:20 AM CDT	Special Weather Statement	MPX	Benton	25 min
Sep 17, 1:29 AM CDT	Severe Thunderstorm Warning	MPX	Brown, Redwood, Renville	31 min
Sep 17, 1:48 AM CDT	Special Weather Statement	MPX	Kanabec, Mille Lacs	27 min
Sep 17, 1:53 AM CDT	Special Weather Statement	MPX	McLeod, Sibley	37 min
Sep 17, 2:00 AM CDT	Special Weather Statement	MPX	Brown, Nicollet	30 min
Sep 17, 2:29 AM CDT	Severe Thunderstorm Warning	MPX	Carver, McLeod, Scott, Sibley	16 min
Sep 17, 2:34 AM CDT	Special Weather Statement	MPX	Le Sueur, Rice	26 min
Sep 17, 2:45 AM CDT	Severe Thunderstorm Warning	MPX	Carver, Hennepin, Scott	15 min
Sep 17, 2:59 AM CDT	Severe Thunderstorm Warning	MPX	Anoka, Dakota, Hennepin, Ramsey, Scott, Washington	16 min
Sep 17, 3:15 AM CDT	Severe Thunderstorm Warning Considerable damage threat	MPX	Washington	15 min
Sep 17, 3:18 AM CDT	Special Weather Statement	MPX	Goodhue	27 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2021 Every severe thunderstorm warning in 2021

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.