Alert archive / Mississippi / Dense Fog Advisories in 2021

Dense Fog Advisory 5, NWS Jackson, MS

April 8, 202115 counties in Mississippi; 9 parishes in Louisiana

NWS Jackson, MS issued this dense fog advisory at Apr 8, 2021, 6:11 AM CDT for 15 counties in Mississippi; 9 parishes in Louisiana. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Apr 8, 2021, 6:11 AM CDT (11:11 UTC)
Expired: Apr 8, 2021, 9:00 AM CDT
In force: 3 hr
Issued by: NWS Jackson, MS

All 24 counties

Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Adams County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Issaquena County, MS, Jefferson County, MS, Lawrence County, MS, Lincoln County, MS, Madison County, MS, Rankin County, MS, Sharkey County, MS, Simpson County, MS, Warren County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 91 km from the middle of the area, began a volume at 11:11 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

Jackson, MS (KJAN), launched 00:00Z, 11.2 hours before the alert went out and 83 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: 652 J/kg
Mixed-layer CIN: -42 J/kg
Mixed-layer LCL: 1178 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 146 m²/s²
0-3 km storm-relative helicity: 256 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 3.4

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 Jackson, MS wrote its last area forecast discussion before this dense fog advisory went out at Apr 8, 5:55 AM CDT, 16 minutes earlier.

Area forecast discussion, Apr 8, 5:55 AM CDT, 16 minutes before

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Hazardous weather outlook, Apr 8, 3:48 AM CDT, 2 hours 23 minutes before

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The office that day

Everything else NWS Jackson, MS issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 7, 8:05 PM CDT	Tornado Warning	JAN	Washington	55 min
Apr 7, 8:41 PM CDT	Special Weather Statement	JAN	Attala	64 min
Apr 7, 8:49 PM CDT	Tornado Warning	JAN	Humphreys, Issaquena, Sharkey, Sunflower, Washington	56 min
Apr 7, 9:24 PM CDT	Severe Thunderstorm Warning	JAN	Carroll, Holmes, Humphreys, Leflore	40 min
Apr 7, 9:43 PM CDT	Severe Thunderstorm Warning	JAN	Adams	47 min
Apr 8, 10:47 AM CDT	River Flood Warning	JAN	Madison, Yazoo	11 days
Apr 8, 10:47 AM CDT	River Flood Warning	JAN	Hinds, Warren	11 days
Apr 8, 10:49 AM CDT	River Flood Warning	JAN	Carroll, Leflore	47 hr
Apr 8, 10:54 AM CDT	River Flood Warning	JAN	Bolivar, Washington	50 hr
Apr 8, 10:57 AM CDT	River Flood Warning	JAN	Issaquena, Washington	5 days
Apr 7, 7:09 PM CDT	Severe Thunderstorm Warning	JAN	Morehouse	66 min
Apr 7, 7:28 PM CDT	Tornado Warning	JAN	Morehouse	47 min
Apr 7, 10:18 PM CDT	Tornado Warning	JAN	Concordia	31 min

Nearby

Dense Fog Advisories in Mississippi, 2021 Dense Fog Advisories in Louisiana, 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.