Alert archive / North Dakota / Dense Fog Advisories in 2021
Dense Fog Advisory 8, NWS Grand Forks, ND
NWS Grand Forks, ND issued this dense fog advisory at May 20, 2021, 10:29 PM CDT for 7 counties in North Dakota; 7 counties in Minnesota. It was in force for 12 hr.
The area
The counties it named.
The facts
- Issued
- May 20, 2021, 10:29 PM CDT (03:29 UTC)
- Expired
- May 21, 2021, 10:00 AM CDT
- In force
- 12 hr
- Issued by
- NWS Grand Forks, ND
Counties Clay County, MN, Marshall County, MN, Norman County, MN, Pennington County, MN, Polk County, MN, Red Lake County, MN, Roseau County, MN, Barnes County, ND, Cass County, ND, Grand Forks County, ND, Griggs County, ND, Ransom County, ND, Steele County, ND, Traill County, ND
The radar
The Fargo/Grand Forks radar (KMVX), 29 km from the middle of the area, began a volume at 03:31 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 00:00Z, 3.5 hours before the alert went out and 297 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
- 858 J/kg
- Mixed-layer CIN
- -29 J/kg
- Mixed-layer LCL
- 1923 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 43 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.4
What forecasters said that day
The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Forks, ND wrote its last area forecast discussion before this dense fog advisory went out at May 20, 9:22 PM CDT, 1 hour 7 minutes earlier.
Area forecast discussion, May 20, 9:22 PM CDT, 1 hour 7 minutes before
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</html>Hazardous weather outlook, May 20, 8:24 PM CDT, 2 hours 5 minutes before
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</html>The office that day
Everything else NWS Grand Forks, ND issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 5:02 PM CDT | Special Weather Statement | FGF | Lake of the Woods | 58 min |
Nearby
Dense Fog Advisories in North Dakota, 2021Dense Fog Advisories in Minnesota, 2021Every dense fog advisory 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.