Alert archive / North Dakota / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 90, NWS Grand Forks, ND
NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 9, 2021, 9:54 PM CDT for Grand Forks County, Steele County, North Dakota; Polk County, Minnesota. It was in force for 66 min. 13 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
- Aug 9, 2021, 9:54 PM CDT (02:54 UTC)
- Expired
- Aug 9, 2021, 11:00 PM CDT
- In force
- 66 min
- Issued by
- NWS Grand Forks, ND
- Area
- Storm-based polygon
- Tornado
- Possible
- Damage threat
- Considerable
- Hail
- 1.5 in
- Wind
- 70.0 mph
Counties Polk County, MN, Grand Forks County, ND, Steele County, ND
The radar
The Fargo/Grand Forks radar (KMVX), 26 km from the middle of the area, began a volume at 02:54 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, 10:09 PM CDT | TSTM WND DMG | 5 Ssw Emerado, ND | A COUPLE OF COTTONWOOD TREES BLOWN OVER. TIME ESTIMATED BASED ON RADAR. |
| Aug 9, 10:30 PM CDT | HAIL 1 | 2 Wnw Grand Forks, ND | REPORT RELAYED VIA SOCIAL MEDIA. |
| Aug 9, 10:30 PM CDT | HAIL 1 | Wnw Grand Forks, ND | REPORT RELAYED VIA SOCIAL MEDIA. |
| Aug 9, 10:35 PM CDT | FUNNEL CLOUD | 5 N Thompson, ND | A WELL DEVELOPED WALL CLOUD WITH BRIEF FUNNEL EVIDENT. WALL CLOUD WAS RAIN WRAPPED. |
| Aug 9, 10:37 PM CDT | TSTM WND GST 69 | 5 Wnw Grand Forks, ND | PEAK WIND MEASURED AT THE GRAND FORKS INTERNATIONAL AIRPORT /KGFK/. |
| Aug 9, 10:38 PM CDT | TSTM WND GST 60 | Grand Forks, ND | 60MPH WIND GUST REPORTED BY UND CLIFFORD HALL ANEMOMETER. |
| Aug 9, 10:38 PM CDT | TSTM WND GST 60 | Grand Forks, ND | PEAKE WIND MEASURED BY UND CLIFFORD HALL ANEMOMETER. |
| Aug 9, 10:38 PM CDT | TSTM WND GST 60 | Grand Forks, ND | PEAK WIND MEASURED BY UND CLIFFORD HALL ANEMOMETER. |
| Aug 9, 10:42 PM CDT | TSTM WND DMG | 1 S Grand Forks, ND | NUMEROUS LARGE BRANCHES AND LIMBS DOWN ALONG BELMONT, SOUTH OF 27TH. |
| Aug 9, 10:44 PM CDT | TSTM WND GST 60 | 2 N East Grand Forks, MN | PEAK WIND MEASURED AT A PERSONAL WEATHER STATION. |
| Aug 9, 10:45 PM CDT | TSTM WND DMG | 2 Wnw Grand Forks, ND | METAL ROOF TORN OFF OF A BUSINESS ALONG U.S. HIGHWAY 2. TIME ESTIMATED BASED ON RADAR AND NEARBY SENSOR OBSERVATIONS. |
| Aug 9, 10:47 PM CDT | TSTM WND DMG | 4 Ne Reynolds, ND | LARGE 4 TO 6 INCH DIAMTER ASH TREE BRANCHES BROKEN DOWN IN A FARMSTEAD. |
| Aug 9, 10:48 PM CDT | TSTM WND GST 62 | 4 Nnw Grand Forks, ND | PEAK WIND MEASURED AT AN NDDOT RWIS STATION. |
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, 2.9 hours before the alert went out and 276 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.
- 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
The text
As transmitted.
531
WUUS53 KFGF 100254
SVRFGF
MNC119-NDC035-091-100400-
/O.NEW.KFGF.SV.W.0090.210810T0254Z-210810T0400Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Forks ND
954 PM CDT Mon Aug 9 2021
The National Weather Service in Grand Forks has issued a
* Severe Thunderstorm Warning for...
Northwestern Polk County in northwestern Minnesota...
Grand Forks County in northeastern North Dakota...
Northeastern Steele County in southeastern North Dakota...
* Until 1100 PM CDT.
* At 954 PM CDT, a severe thunderstorm was located near Arvilla, or
22 miles west of Grand Forks, moving east at 25 mph.
HAZARD...70 mph wind gusts and ping pong ball size hail.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect
considerable tree damage. Wind damage is also likely to
mobile homes, roofs, and outbuildings.
* This severe thunderstorm will be near...
Arvilla around 1000 PM CDT.
Other locations in the path of this severe thunderstorm include
Emerado, Grand Forks AFB, Mekinock, Merrifield and Grand Forks.
This includes Interstate 29 between mile markers 125 and 155.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4772 9694 4767 9728 4767 9747 4764 9748
4758 9788 4797 9771 4815 9708
TIME...MOT...LOC 0254Z 254DEG 21KT 4788 9754
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
$$
TG1 follow-up statement
603
WWUS53 KFGF 100322
SVSFGF
Severe Weather Statement
National Weather Service Grand Forks ND
1022 PM CDT Mon Aug 9 2021
NDC091-100331-
/O.CAN.KFGF.SV.W.0090.000000T0000Z-210810T0400Z/
Steele ND-
1022 PM CDT Mon Aug 9 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN STEELE COUNTY IS
CANCELLED...
The storms which prompted the warning have moved out of the warned
area. Therefore, the warning has been cancelled.
A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
northwestern Minnesota...and southeastern and northeastern North
Dakota.
LAT...LON 4772 9694 4767 9726 4767 9751 4804 9748
4815 9708
TIME...MOT...LOC 0321Z 258DEG 27KT 4807 9727 4769 9727
$$
MNC119-NDC035-100400-
/O.CON.KFGF.SV.W.0090.000000T0000Z-210810T0400Z/
Polk MN-Grand Forks ND-
1022 PM CDT Mon Aug 9 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM CDT
FOR NORTHWESTERN POLK AND CENTRAL GRAND FORKS COUNTIES...
At 1021 PM CDT, severe thunderstorms were located along a line
extending from near Manvel to near Holmes, moving east at 30 mph.
HAZARD...70 mph wind gusts and ping pong ball size hail.
SOURCE...Radar indicated.
IMPACT...People and animals outdoors will be injured. Expect hail
damage to roofs, siding, windows, and vehicles. Expect
considerable tree damage. Wind damage is also likely to
mobile homes, roofs, and outbuildings.
Locations impacted include...
Manvel and Thompson.
This includes Interstate 29 between mile markers 125 and 155.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4772 9694 4767 9726 4767 9751 4804 9748
4815 9708
TIME...MOT...LOC 0321Z 258DEG 27KT 4807 9727 4769 9727
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
$$
TGThe 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 | 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 | FGF | Eddy, Griggs, Nelson | 63 min |
| Aug 9, 8:28 PM CDT | Tornado Warning | FGF | Griggs, Nelson | 32 min |
| Aug 9, 8:52 PM CDT | Severe Thunderstorm Warning | FGF | Cavalier, Pembina | 38 min |
| Aug 9, 9:09 PM CDT | Severe Thunderstorm Warning | 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, 10:08 PM CDT | Special Weather Statement | FGF | Pembina | 52 min |
| Aug 9, 10:30 PM CDT | Severe Thunderstorm Warning | FGF | Grand Forks, Steele, Traill | 30 min |
| Aug 9, 10:42 PM CDT | Severe Thunderstorm Warning | FGF | Grand Forks, Traill | 63 min |
| Aug 9, 11:05 PM CDT | Tornado Warning | FGF | Polk | 25 min |
| Aug 9, 11:29 PM CDT | Severe Thunderstorm Warning | FGF | Marshall, Pennington, Polk, Red Lake | 61 min |
| Aug 10, 2:20 AM CDT | Special Weather Statement | FGF | Lake of the Woods | 25 min |
| Aug 10, 2:55 AM CDT | Special Weather Statement | FGF | Lake of the Woods | 35 min |
Nearby
Severe Thunderstorm Warnings in North Dakota, 2021Severe Thunderstorm Warnings in Minnesota, 2021Every 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.