Alert archive / Minnesota / Dense Fog Advisories in 2021

Dense Fog Advisory 9, NWS Grand Forks, ND

July 20, 20215 counties in North Dakota; 14 counties in Minnesota

NWS Grand Forks, ND issued this dense fog advisory at Jul 20, 2021, 3:08 AM CDT for 5 counties in North Dakota; 14 counties in Minnesota. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Jul 20, 2021, 3:08 AM CDT (08:08 UTC)
Expired: Jul 20, 2021, 10:00 AM CDT
In force: 7 hr
Issued by: NWS Grand Forks, ND

Counties Becker County, MN, Beltrami County, MN, Clearwater County, MN, Hubbard County, MN, Kittson County, MN, Lake of the Woods County, MN, Mahnomen County, MN, Marshall County, MN, Norman County, MN, Pennington County, MN, Polk County, MN, Red Lake County, MN, Roseau County, MN, Wadena County, MN, Cavalier County, ND, Grand Forks County, ND, Pembina County, ND, Traill County, ND, Walsh County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 91 km from the middle of the area, began a volume at 08:08 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

International Fa, MN (KINL), launched 00:00Z, 8.1 hours before the alert went out and 231 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: 873 J/kg
Mixed-layer CIN: -129 J/kg
Mixed-layer LCL: 1160 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 57 m²/s²
0-3 km storm-relative helicity: 112 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.2

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 Jul 20, 12:03 AM CDT, 3 hours 5 minutes earlier.

Area forecast discussion, Jul 20, 12:03 AM CDT, 3 hours 5 minutes before

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Hazardous weather outlook, Jul 19, 8:35 AM CDT, 18 hours 33 minutes before

Hazardous Weather Outlook
National Weather Service Grand Forks ND
835 AM CDT Mon Jul 19 2021

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-201345-
West Polk-Norman-Clay-Kittson-Roseau-Lake Of The Woods-
West Marshall-East Marshall-North Beltrami-Pennington-Red Lake-
East Polk-North Clearwater-South Beltrami-Mahnomen-
South Clearwater-Hubbard-West Becker-East Becker-Wilkin-
West Otter Tail-East Otter Tail-Wadena-Grant-Towner-Cavalier-
Pembina-Benson-Ramsey-Eastern Walsh-Eddy-Nelson-Grand Forks-
Griggs-Steele-Traill-Barnes-Cass-Ransom-Sargent-Richland-
Western Walsh-
835 AM CDT Mon Jul 19 2021

This hazardous weather outlook is for portions of eastern North
Dakota, west central and northwest Minnesota.

.DAY ONE...Today and Tonight

Widely scattered thunderstorms are possible today into tonight. A
few storms may be strong to severe bringing gusty winds up to 60
mph and large hail up to one inch.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Isolated thunderstorms are possible about every day, mainly during
the evening and overnight periods. These storms could bring needed
rainfall to small areas, or due to their slow movement, could also
bring heavy amounts of rain to small areas.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

PJS

In the hours before

Local storm report, Jul 19, 9:28 PM CDT, 5 hours 40 minutes before

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Local storm report, Jul 19, 10:13 PM CDT, 4 hours 55 minutes before

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Local storm report, Jul 19, 10:14 PM CDT, 4 hours 54 minutes before

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Local storm report, Jul 19, 10:36 PM CDT, 4 hours 32 minutes before

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Local storm report, Jul 19, 11:46 PM CDT, 3 hours 22 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS ND
1146 PM CDT MON JUL 19 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0105 PM     TSTM WND GST     KEMPTON                 47.82N 97.61W
07/19/2021  E65 MPH          GRAND FORKS        ND   PUBLIC

            CORRECTS PREVIOUS TSTM WND GST REPORT FROM
            KEMPTON. CORRECTS PREVIOUS TSTM WND GST
            REPORT FROM KEMPTON. ESTIMATED 60 TO 70 MPH
            WIND GUST.

&&

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 19, 7:35 PM CDT	Special Weather Statement	FGF	Benson, Eddy, Nelson, Ramsey	55 min
Jul 19, 8:31 PM CDT	Special Weather Statement	FGF	Grand Forks	59 min
Jul 19, 8:58 PM CDT	Severe Thunderstorm Warning	FGF	Marshall, Polk	32 min
Jul 20, 5:37 AM CDT	Special Weather Statement	FGF	Lake of the Woods, Roseau	53 min

Nearby

Dense Fog Advisories in Minnesota, 2021 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.