Alert archive / Louisiana / Winter Weather Advisories in 2021

Winter Weather Advisory 2, NWS New Orleans, LA

February 16, 202113 parishes in Louisiana; 5 counties in Mississippi

NWS New Orleans, LA issued this winter weather advisory at Feb 16, 2021, 10:02 PM CST for 13 parishes in Louisiana; 5 counties in Mississippi. It took effect at Feb 17, 2021, 5:00 AM CST. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Feb 16, 2021, 10:02 PM CST (04:02 UTC)
In effect from: Feb 17, 2021, 5:00 AM CST
Expired: Feb 17, 2021, 12:00 PM CST
In force: 7 hr
Issued by: NWS New Orleans, LA

Counties Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Pointe Coupee Parish, LA, Saint Bernard Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Amite County, MS, Pearl River County, MS, Pike County, MS, Walthall County, MS, Wilkinson County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 4.0 hours before the alert went out and 108 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: 1123 m above ground
0-6 km bulk shear: 74 kt
0-1 km storm-relative helicity: -30 m²/s²
0-3 km storm-relative helicity: 91 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 New Orleans, LA wrote its last area forecast discussion before this winter weather advisory went out at Feb 16, 8:58 PM CST, 1 hour 4 minutes earlier.

Area forecast discussion, Feb 16, 8:58 PM CST, 1 hour 4 minutes before

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The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 16, 6:21 PM CST	Freeze Warning	LIX	Assumption, Saint Bernard, Saint James, Saint John the Baptist	14 hr
Feb 16, 6:21 PM CST	Hard Freeze Warning	LIX	East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Helena, Tangipahoa and 3 more	14 hr
Feb 17, 12:03 PM CST	Winter Weather Advisory	LIX	East Feliciana, Pointe Coupee, West Feliciana	57 min
Feb 17, 2:29 PM CST	Winter Weather Advisory	LIX	East Feliciana, Pointe Coupee, West Feliciana	9 hr

Nearby

Winter Weather Advisories in Louisiana, 2021 Winter Weather Advisories in Mississippi, 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.