Alert archive / North Dakota / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 78, NWS Grand Forks, ND

August 4, 2021Towner County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 4, 2021, 6:43 PM CDT for Towner County, North Dakota. It was in force for 21 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: Aug 4, 2021, 6:43 PM CDT (23:43 UTC)
Expired: Aug 4, 2021, 7:04 PM CDT
In force: 21 min
Issued by: NWS Grand Forks, ND
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

County Towner County, ND

The radar

The Minot AFB radar (KMBX), 113 km from the middle of the area, began a volume at 23:42 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 nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 11.7 hours before the alert went out and 238 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: 18 J/kg
Mixed-layer CIN: -192 J/kg
Mixed-layer LCL: 1486 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 16 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

312 
WUUS53 KFGF 042343
SVRFGF
NDC095-050045-
/O.NEW.KFGF.SV.W.0078.210804T2343Z-210805T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Forks ND
643 PM CDT Wed Aug 4 2021

The National Weather Service in Grand Forks has issued a

* Severe Thunderstorm Warning for...
  Northwestern Towner County in northeastern North Dakota...

* Until 745 PM CDT.

* At 642 PM CDT, a severe thunderstorm was located near Rolla, or 53
  miles west of Langdon, moving southeast at 20 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Perth, Rocklake, Bisbee, Arndt and Considine.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4892 9953 4876 9906 4849 9934 4861 9949
      4872 9949 4872 9952
TIME...MOT...LOC 2342Z 306DEG 15KT 4880 9954 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...<50 MPH

$$

PJS

1 follow-up statement

182 
WWUS53 KFGF 050004
SVSFGF

Severe Weather Statement
National Weather Service Grand Forks ND
704 PM CDT Wed Aug 4 2021

NDC095-050014-
/O.CAN.KFGF.SV.W.0078.000000T0000Z-210805T0045Z/
Towner ND-
704 PM CDT Wed Aug 4 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN TOWNER COUNTY 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.

LAT...LON 4892 9953 4876 9906 4849 9934 4861 9949
      4872 9949 4872 9952
TIME...MOT...LOC 0002Z 306DEG 15KT 4875 9943 

$$

PJS

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.