Alert archive / Mississippi / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 364, NWS Jackson, MS

July 21, 2020Grenada County, Montgomery County, Mississippi

NWS Jackson, MS issued this severe thunderstorm warning at Jul 21, 2020, 3:10 PM CDT for Grenada County, Montgomery County, Mississippi. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 21, 2020, 3:10 PM CDT (20:10 UTC)
Expired: Jul 21, 2020, 3:42 PM CDT
In force: 32 min
Issued by: NWS Jackson, MS
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Grenada County, MS, Montgomery County, MS

The radar

The Columbus AFB radar (KGWX), 131 km from the middle of the area, began a volume at 20:11 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

Little Rock, AR (KLZK), launched 12:00Z, 8.2 hours before the alert went out and 135 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: 1038 J/kg
Mixed-layer CIN: -54 J/kg
Mixed-layer LCL: 1070 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: -24 m²/s²
0-3 km storm-relative helicity: -11 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 8:23 PM CDT	Special Weather Statement	JAN	Clay	22 min
Jul 20, 9:08 PM CDT	Special Weather Statement	JAN	Clay	37 min
Jul 21, 1:36 PM CDT	Special Weather Statement	JAN	Lowndes	39 min
Jul 21, 1:42 PM CDT	Special Weather Statement	JAN	Winston	33 min
Jul 21, 2:05 PM CDT	Special Weather Statement	JAN	Webster	40 min
Jul 21, 2:18 PM CDT	Special Weather Statement	JAN	Choctaw	42 min
Jul 21, 2:25 PM CDT	Special Weather Statement	JAN	Jefferson Davis	50 min
Jul 21, 2:54 PM CDT	Special Weather Statement	JAN	Grenada	51 min
Jul 21, 1:51 PM CDT	Special Weather Statement	JAN	Concordia	39 min
Jul 21, 3:14 PM CDT	Special Weather Statement	JAN	Catahoula	16 min
Jul 21, 3:31 PM CDT	Special Weather Statement	JAN	Tensas	29 min
Jul 21, 4:02 PM CDT	Special Weather Statement	JAN	Franklin	43 min
Jul 21, 5:25 PM CDT	Special Weather Statement	JAN	Morehouse	50 min

Nearby

Severe Thunderstorm Warnings in Mississippi, 2020 Every severe thunderstorm warning in 2020

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.