Alert archive / Mississippi / Winter Weather Advisories in 2021

Winter Weather Advisory 7, NWS Memphis, TN

February 18, 202122 counties in Mississippi; 21 counties in Tennessee

NWS Memphis, TN issued this winter weather advisory at Feb 18, 2021, 9:07 AM CST for 22 counties in Mississippi; 21 counties in Tennessee. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued: Feb 18, 2021, 9:07 AM CST (15:07 UTC)
Expired: Feb 18, 2021, 2:54 PM CST
In force: 6 hr
Issued by: NWS Memphis, TN

All 43 counties

Alcorn County, MS, Benton County, MS, Calhoun County, MS, Chickasaw County, MS, Coahoma County, MS, DeSoto County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Marshall County, MS, Monroe County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Tunica County, MS, Union County, MS, Yalobusha County, MS, Benton County, TN, Carroll County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Henry County, TN, Lake County, TN, Lauderdale County, TN, Madison County, TN, McNairy County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN

The radar

The Memphis radar (KNQA), 75 km from the middle of the area, began a volume at 15:10 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

Nashville Metro, TN (KBNA), launched 12:00Z, 3.1 hours before the alert went out and 258 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 434 m above ground
0-6 km bulk shear: 103 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 113 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this winter weather advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Memphis, TN wrote its last area forecast discussion before this winter weather advisory went out at Feb 17, 5:31 PM CST, 15 hours 36 minutes earlier.

Area forecast discussion, Feb 17, 5:31 PM CST, 15 hours 36 minutes before

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The office that day

Everything else NWS Memphis, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 18, 2:54 PM CST	Wind Chill Advisory	MEG	DeSoto, Tunica	18 hr
Feb 18, 2:54 PM CST	Winter Weather Advisory	MEG	Alcorn, Calhoun, Chickasaw, Itawamba, Lafayette, Lee and 8 more	3 hr

Nearby

Winter Weather Advisories in Mississippi, 2021 Winter Weather Advisories in Tennessee, 2021 Every winter weather 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.