Alert archive / North Dakota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 88, NWS Grand Forks, ND

August 9, 2021Cavalier County, Pembina County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 9, 2021, 8:52 PM CDT for Cavalier County, Pembina County, North Dakota. It was in force for 38 min. 1 report 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: Aug 9, 2021, 8:52 PM CDT (01:52 UTC)
Expired: Aug 9, 2021, 9:30 PM CDT
In force: 38 min
Issued by: NWS Grand Forks, ND
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

Counties Cavalier County, ND, Pembina County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 161 km from the middle of the area, began a volume at 01:54 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
Aug 9, 9:03 PM CDT	HAIL 1	2 Sse Walhalla, ND

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
Aug 9, 4:01 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.9 hours before the alert went out and 300 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: 296 J/kg
Mixed-layer CIN: -462 J/kg
Mixed-layer LCL: 1238 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: -40 m²/s²
0-3 km storm-relative helicity: 31 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

013 
WUUS53 KFGF 100152
SVRFGF
NDC019-067-100230-
/O.NEW.KFGF.SV.W.0088.210810T0152Z-210810T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Forks ND
852 PM CDT Mon Aug 9 2021

The National Weather Service in Grand Forks has issued a

* Severe Thunderstorm Warning for...
  Eastern Cavalier County in northeastern North Dakota...
  Northwestern Pembina County in northeastern North Dakota...

* Until 930 PM CDT.

* At 851 PM CDT, a severe thunderstorm was located near Walhalla, or
  18 miles northeast of Langdon, moving northeast at 35 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...
  Walhalla around 900 PM CDT.
  Leroy around 910 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This thunderstorm is capable of producing all types of severe weather
including extremely large hail, destructive straight line winds and
tornadoes. Move quickly to a safe shelter such as an interior room, a
bathroom, closet or basement.

&&

LAT...LON 4900 9768 4889 9753 4862 9826 4865 9848
      4878 9864 4894 9858 4900 9844
TIME...MOT...LOC 0151Z 234DEG 32KT 4888 9800 

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

$$

Lynch

1 follow-up statement

422 
WWUS53 KFGF 100211
SVSFGF

Severe Weather Statement
National Weather Service Grand Forks ND
911 PM CDT Mon Aug 9 2021

NDC019-067-100230-
/O.CON.KFGF.SV.W.0088.000000T0000Z-210810T0230Z/
Cavalier ND-Pembina ND-
911 PM CDT Mon Aug 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM CDT
FOR NORTHEASTERN CAVALIER AND NORTHWESTERN PEMBINA COUNTIES...

At 911 PM CDT, a severe thunderstorm was located near Leroy, or 30
miles northeast of Langdon, moving northeast at 35 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 remain over mainly rural areas of
northeastern Cavalier and northwestern Pembina Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4889 9753 4874 9795 4899 9816 4900 9814
      4900 9768
TIME...MOT...LOC 0211Z 234DEG 32KT 4899 9778 

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

$$

Lynch

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 7:04 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier, Ramsey, Towner	56 min
Aug 9, 7:11 PM CDT	Tornado Warning	FGF	Cavalier, Ramsey, Towner	34 min
Aug 9, 7:29 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FGF	Eddy, Griggs, Nelson	46 min
Aug 9, 7:57 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier, Pembina, Ramsey, Walsh	63 min
Aug 9, 8:08 PM CDT	Severe Thunderstorm Warning	FGF	Grand Forks, Nelson	27 min
Aug 9, 8:12 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FGF	Eddy, Griggs, Nelson	63 min
Aug 9, 8:28 PM CDT	Tornado Warning	FGF	Griggs, Nelson	32 min
Aug 9, 9:09 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FGF	Grand Forks, Griggs, Nelson, Steele	66 min
Aug 9, 9:20 PM CDT	Tornado Warning	FGF	Grand Forks, Nelson, Steele	40 min
Aug 9, 9:42 PM CDT	Tornado Warning	FGF	Grand Forks	48 min
Aug 9, 9:54 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FGF	Grand Forks, Steele	66 min
Aug 9, 10:08 PM CDT	Special Weather Statement	FGF	Pembina	52 min
Aug 9, 10:30 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FGF	Grand Forks, Steele, Traill	30 min
Aug 9, 10:42 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FGF	Grand Forks, Traill	63 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 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.