Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 114, NWS Grand Forks, ND

September 15, 2021Marshall County, Pennington County, Polk County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Sep 15, 2021, 11:25 PM CDT for Marshall County, Pennington County, Polk County, Minnesota. It was in force for 50 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 15, 2021, 11:25 PM CDT (04:25 UTC)
Expired: Sep 16, 2021, 12:15 AM CDT
In force: 50 min
Issued by: NWS Grand Forks, ND
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Marshall County, MN, Pennington County, MN, Polk County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 80 km from the middle of the area, began a volume at 04:26 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	Remark
Sep 15, 11:33 PM CDT	TSTM WND GST 59	6 Sw Warren, MN	PEAK WIND MEASURED AT AN NDAWN STATION AT 3 METERS.
Sep 15, 11:33 PM CDT	TSTM WND GST 59	6 Sw Warren, MN	VIA NDAWN.
Sep 15, 11:38 PM CDT	TSTM WND GST 57	4 S Warren, MN	RELAYED VIA SOCIAL MEDIA. TIME ESTIMATED BASED ON RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 4.4 hours before the alert went out and 256 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: 6 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 1751 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 110 m²/s²
0-3 km storm-relative helicity: 145 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

819 
WUUS53 KFGF 160425
SVRFGF
MNC089-113-119-160530-
/O.NEW.KFGF.SV.W.0114.210916T0425Z-210916T0530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Forks ND
1125 PM CDT Wed Sep 15 2021

The National Weather Service in Grand Forks has issued a

* Severe Thunderstorm Warning for...
  Southwestern Marshall County in northwestern Minnesota...
  Northwestern Polk County in northwestern Minnesota...
  Western Pennington County in northwestern Minnesota...

* Until 1230 AM CDT.

* At 1125 PM CDT, a severe thunderstorm was located near Tabor, or 17
  miles northeast of Grand Forks, moving east at 40 mph.

  HAZARD...60 mph wind gusts and quarter 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...
  Sherack around 1130 PM CDT.
  Warren and Angus around 1135 PM CDT.
  Radium around 1145 PM CDT.

Other locations in the path of this severe thunderstorm include
Carpenters Corner and Viking.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4797 9701 4819 9713 4843 9624 4799 9611
TIME...MOT...LOC 0425Z 254DEG 34KT 4812 9688 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Lynch

2 follow-up statements

968 
WWUS53 KFGF 160459
SVSFGF

Severe Weather Statement
National Weather Service Grand Forks ND
1159 PM CDT Wed Sep 15 2021

MNC089-113-119-160530-
/O.CON.KFGF.SV.W.0114.000000T0000Z-210916T0530Z/
Marshall MN-Polk MN-Pennington MN-
1159 PM CDT Wed Sep 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1230 AM CDT
FOR SOUTH CENTRAL MARSHALL...NORTH CENTRAL POLK AND WESTERN
PENNINGTON COUNTIES...

At 1158 PM CDT, a severe thunderstorm was located over Viking, or 13
miles northwest of Thief River Falls, moving east at 40 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
  Viking, Rosewood, Holt, Dakota Junction and Thief River Falls.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4798 9667 4812 9685 4824 9678 4838 9622
      4799 9611
TIME...MOT...LOC 0458Z 254DEG 34KT 4821 9643 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Lynch

908 
WWUS53 KFGF 160515
SVSFGF

Severe Weather Statement
National Weather Service Grand Forks ND
1215 AM CDT Thu Sep 16 2021

MNC089-113-119-160525-
/O.CAN.KFGF.SV.W.0114.000000T0000Z-210916T0530Z/
Marshall MN-Polk MN-Pennington MN-
1215 AM CDT Thu Sep 16 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL MARSHALL...NORTH
CENTRAL POLK AND WESTERN PENNINGTON COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However small hail and
gusty winds are still possible with this thunderstorm.

LAT...LON 4798 9667 4812 9685 4824 9678 4838 9622
      4799 9611
TIME...MOT...LOC 0514Z 254DEG 34KT 4825 9619 

$$

Lynch

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 15, 10:38 PM CDT	Severe Thunderstorm Warning	FGF	Kittson, Marshall	52 min
Sep 15, 10:47 PM CDT	Severe Thunderstorm Warning	FGF	Marshall, Polk	43 min
Sep 15, 11:27 PM CDT	Special Weather Statement	FGF	Marshall	48 min
Sep 15, 11:45 PM CDT	Severe Thunderstorm Warning	FGF	Polk	60 min
Sep 16, 12:14 AM CDT	Special Weather Statement	FGF	Pennington	46 min
Sep 16, 12:22 AM CDT	Special Weather Statement	FGF	Polk, Red Lake	38 min
Sep 16, 12:42 AM CDT	Severe Thunderstorm Warning	FGF	Polk, Red Lake	33 min
Sep 16, 1:13 AM CDT	Special Weather Statement	FGF	Red Lake	32 min
Sep 16, 1:23 AM CDT	Special Weather Statement	FGF	Mahnomen	37 min
Sep 16, 1:51 AM CDT	Special Weather Statement	FGF	Beltrami, Clearwater	54 min
Sep 16, 1:59 AM CDT	Severe Thunderstorm Warning	FGF	Beltrami, Clearwater, Hubbard, Mahnomen, Polk	49 min
Sep 16, 2:44 AM CDT	Special Weather Statement	FGF	Hubbard	46 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.