Alert archive / North Dakota / Dense Fog Advisories in 2021

Dense Fog Advisory 10, NWS Grand Forks, ND

August 28, 202110 counties in North Dakota

NWS Grand Forks, ND issued this dense fog advisory at Aug 28, 2021, 12:41 AM CDT for 10 counties in North Dakota. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued: Aug 28, 2021, 12:41 AM CDT (05:41 UTC)
Expired: Aug 28, 2021, 11:41 AM CDT
In force: 11 hr
Issued by: NWS Grand Forks, ND

Counties Benson County, ND, Cavalier County, ND, Eddy County, ND, Grand Forks County, ND, Griggs County, ND, Nelson County, ND, Pembina County, ND, Ramsey County, ND, Towner County, ND, Walsh County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 108 km from the middle of the area, began a volume at 05:40 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, 5.7 hours before the alert went out and 235 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: 460 J/kg
Mixed-layer CIN: -133 J/kg
Mixed-layer LCL: 1088 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 52 m²/s²
0-3 km storm-relative helicity: 80 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

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 Aug 27, 11:38 PM CDT, 1 hour 3 minutes earlier.

Area forecast discussion, Aug 27, 11:38 PM CDT, 1 hour 3 minutes before

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Hazardous weather outlook, Aug 27, 10:12 PM CDT, 2 hours 29 minutes before

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In the hours before

Local storm report, Aug 27, 7:45 PM CDT, 4 hours 56 minutes before

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Local storm report, Aug 27, 7:46 PM CDT, 4 hours 55 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 28, 7:31 AM CDT	Special Weather Statement	FGF	Sargent	44 min
Aug 28, 8:48 AM CDT	Special Weather Statement	FGF	Grand Forks	57 min
Aug 28, 6:59 AM CDT	Special Weather Statement	FGF	Marshall	61 min
Aug 28, 8:11 AM CDT	Special Weather Statement	FGF	Roseau	49 min
Aug 28, 9:01 AM CDT	Special Weather Statement	FGF	Grant	44 min
Aug 28, 9:04 AM CDT	Special Weather Statement	FGF	Roseau	56 min
Aug 28, 9:48 AM CDT	Special Weather Statement	FGF	Grant	57 min

Nearby

Dense Fog Advisories in North Dakota, 2021 Every 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.