Alert archive / Minnesota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 61, NWS Grand Forks, ND

July 24, 2021Becker County, Otter Tail County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 24, 2021, 1:05 AM CDT for Becker County, Otter Tail County, Minnesota. It was in force for 40 min. 4 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: Jul 24, 2021, 1:05 AM CDT (06:05 UTC)
Expired: Jul 24, 2021, 1:45 AM CDT
In force: 40 min
Issued by: NWS Grand Forks, ND
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Becker County, MN, Otter Tail County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 163 km from the middle of the area, began a volume at 06:08 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
Jul 24, 1:08 AM CDT	HAIL 1.25	Frazee, MN	REPORT POSTED VIA SOCIAL MEDIA.
Jul 24, 1:08 AM CDT	HAIL 1.25	Frazee, MN
Jul 24, 1:41 AM CDT	TSTM WND GST 53	2 Nw Perham, MN	MEASURED AT NDAWN STATION.
Jul 24, 1:41 AM CDT	TSTM WND GST 53	2 Nw Perham, MN	PEAK WIND MEASURED AT AN NDANW STATION AT 3 METERS.

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
Jul 23, 11:22 PM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 6.1 hours before the alert went out and 254 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: 2540 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 1098 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 124 m²/s²
0-3 km storm-relative helicity: 143 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.4

Open this sounding in Storm Lab

The text

As transmitted.

673 
WUUS53 KFGF 240605
SVRFGF
MNC005-111-240645-
/O.NEW.KFGF.SV.W.0061.210724T0605Z-210724T0645Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Forks ND
105 AM CDT Sat Jul 24 2021

The National Weather Service in Grand Forks has issued a

* Severe Thunderstorm Warning for...
  Northeastern Otter Tail County in west central Minnesota...
  Southeastern Becker County in northwestern Minnesota...

* Until 145 AM CDT.

* At 105 AM CDT, a severe thunderstorm was located over Frazee, or 9
  miles southeast of Detroit Lakes, moving southeast at 20 mph.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           wind damage to roofs, siding, and trees.

* Locations impacted include...
  Perham, Evergreen and Butler.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4663 9579 4682 9579 4678 9522 4658 9518
TIME...MOT...LOC 0605Z 296DEG 18KT 4673 9570 

HAIL...1.50IN
WIND...60MPH
 
$$

Riddle

1 follow-up statement

872 
WWUS53 KFGF 240637
SVSFGF

Severe Weather Statement
National Weather Service Grand Forks ND
137 AM CDT Sat Jul 24 2021

MNC005-111-240647-
/O.EXP.KFGF.SV.W.0061.000000T0000Z-210724T0645Z/
Otter Tail MN-Becker MN-
137 AM CDT Sat Jul 24 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN OTTER TAIL AND
SOUTHEASTERN BECKER COUNTIES WILL EXPIRE AT 145 AM CDT...
                
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 will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 500 AM CDT for
west central Minnesota.

LAT...LON 4663 9579 4682 9579 4678 9522 4658 9518
TIME...MOT...LOC 0637Z 296DEG 18KT 4666 9550 

$$

Riddle

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 11:50 PM CDT	Special Weather Statement	FGF	Wilkin	55 min
Jul 24, 12:41 AM CDT	Severe Thunderstorm Warning	FGF	Grant, Otter Tail, Wilkin	49 min
Jul 24, 12:58 AM CDT	Severe Thunderstorm Warning	FGF	Grant	47 min
Jul 24, 1:34 AM CDT	Severe Thunderstorm Warning	FGF	Grant, Otter Tail	41 min
Jul 24, 1:51 AM CDT	Severe Thunderstorm Warning	FGF	Otter Tail, Wadena	39 min
Jul 24, 2:32 AM CDT	Special Weather Statement	FGF	Hubbard	58 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.