Alert archive / Mississippi / Areal Flood Warnings in 2021

Areal Flood Warning 10, NWS New Orleans, LA

August 30, 2021Saint Tammany Parish, Washington Parish, Louisiana; 4 counties in Mississippi

NWS New Orleans, LA issued this areal flood warning at Aug 30, 2021, 11:34 AM CDT for Saint Tammany Parish, Washington Parish, Louisiana; 4 counties in Mississippi. It was in force for 34 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 30, 2021, 11:34 AM CDT (16:34 UTC)
Expired: Aug 31, 2021, 9:45 PM CDT
In force: 34 hr
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Flood severity: None

Counties Saint Tammany Parish, LA, Washington Parish, LA, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 4.6 hours before the alert went out and 41 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: 881 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 560 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 386 m²/s²
0-3 km storm-relative helicity: 386 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 9.7

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood warning 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 areal flood warning went out at Aug 30, 11:21 AM CDT, 13 minutes earlier.

Area forecast discussion, Aug 30, 11:21 AM CDT, 13 minutes before

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In the hours before

Local storm report, Aug 30, 11:32 AM CDT, 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1132 AM CDT MON AUG 30 2021

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

0945 AM     TORNADO          3 E ESCATAWPA           30.48N 88.51W
08/30/2021                   JACKSON            MS   EMERGENCY MNGR

            EMERGENCY MANAGER RELAYED PUBLIC REPORT OF
            POSSIBLE TORNADO DAMAGE AT THE INTERSECTION
            OF CODA ROAD AND SARACENNIA ROAD. TIME
            ESTIMATED.

&&

KLG

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 29, 7:48 PM CDT	Flash Flood Warning Considerable damage threat	LIX	Saint Charles, Saint John the Baptist	2 hr
Aug 29, 8:00 PM CDT	Special Marine Warning	LIX		30 min
Aug 29, 8:22 PM CDT	Tornado Warning	LIX	Saint Tammany	38 min
Aug 29, 8:35 PM CDT	Flash Flood Warning EmergencyCatastrophic damage threat	LIX	Saint Charles, Saint John the Baptist	6 hr
Aug 29, 8:55 PM CDT	Flash Flood Warning EmergencyConsiderable damage threat	LIX	Livingston, Tangipahoa	3 hr
Aug 29, 9:05 PM CDT	River Flood Warning	LIX	Saint Tammany	12 days
Aug 29, 9:05 PM CDT	River Flood Warning	LIX	Saint Tammany	21 days
Aug 29, 9:05 PM CDT	River Flood Warning	LIX	Washington	63 hr
Aug 29, 9:05 PM CDT	River Flood Warning	LIX	Saint Tammany, Washington	11 days
Aug 29, 10:39 PM CDT	Special Marine Warning	LIX		51 min
Aug 29, 10:48 PM CDT	Flash Flood Warning EmergencyCatastrophic damage threat	LIX	Jefferson	15 hr
Aug 29, 10:55 PM CDT	Special Marine Warning	LIX		20 min
Aug 29, 11:45 PM CDT	Flash Flood Warning EmergencyCatastrophic damage threat	LIX	Plaquemines	10 hr
Aug 29, 11:50 PM CDT	Flash Flood Warning Considerable damage threat	LIX	Livingston, Saint Helena, Saint Tammany, Tangipahoa, Washington	3 hr
Aug 30, 12:05 AM CDT	Flash Flood Warning EmergencyCatastrophic damage threat	LIX	Livingston, Tangipahoa	12 hr
Aug 30, 1:24 AM CDT	Flash Flood Warning	LIX	Livingston, Saint Helena	8 hr
Aug 30, 2:24 AM CDT	Flash Flood Warning EmergencyCatastrophic damage threat	LIX	Saint Charles, Saint John the Baptist	8 hr
Aug 30, 2:39 AM CDT	Flash Flood Warning Considerable damage threat	LIX	Saint Tammany	9 hr
Aug 30, 2:55 AM CDT	Flash Flood Warning Considerable damage threat	LIX	Livingston, Saint Helena, Saint Tammany, Tangipahoa, Washington	5 hr
Aug 30, 3:55 AM CDT	Flash Flood Warning	LIX	East Feliciana, Saint Helena, Tangipahoa, Washington	5 hr
Aug 30, 4:19 AM CDT	Small Craft Advisory	LIX		39 hr
Aug 30, 4:51 AM CDT	Coastal Flood Advisory	LIX	Assumption	15 hr
Aug 30, 7:15 AM CDT	Special Marine Warning	LIX		30 min
Aug 30, 7:18 AM CDT	Special Marine Warning	LIX		27 min
Aug 30, 7:45 AM CDT	Flash Flood Warning	LIX	Livingston, Saint Helena, Saint Tammany, Tangipahoa, Washington	3 hr
Aug 30, 9:01 AM CDT	Special Marine Warning	LIX		89 min
Aug 30, 9:58 AM CDT	Areal Flood Warning	LIX	Jefferson, Lafourche, Livingston, Plaquemines, Saint Charles, Saint James and 1 more	60 hr
Aug 30, 10:53 AM CDT	Areal Flood Warning	LIX	Saint Tammany, Tangipahoa, Washington	35 hr
Aug 30, 11:04 AM CDT	Areal Flood Warning	LIX	Saint Helena, Saint Tammany, Tangipahoa, Washington	35 hr
Aug 30, 12:24 PM CDT	Areal Flood Warning	LIX	Ascension, Livingston, Saint John the Baptist, Saint Tammany, Tangipahoa	33 hr
Aug 30, 2:57 PM CDT	Heat Advisory	LIX	Assumption, East Baton Rouge, Iberville, Orleans, Saint Bernard, Saint James and 2 more	26 hr
Aug 30, 6:10 PM CDT	Special Marine Warning	LIX		95 min
Aug 29, 9:04 PM CDT	Tornado Warning	LIX	Hancock, Harrison, Pearl River	26 min
Aug 29, 9:05 PM CDT	River Flood Warning	LIX	Pike, Walthall	38 hr
Aug 29, 9:06 PM CDT	River Flood Warning	LIX	Jackson	9 days
Aug 29, 9:32 PM CDT	Tornado Warning	LIX	Hancock, Pearl River	13 min
Aug 29, 9:36 PM CDT	Tornado Warning	LIX	Hancock, Harrison, Pearl River	24 min
Aug 29, 10:01 PM CDT	Tornado Warning	LIX	Hancock, Harrison, Pearl River	14 min
Aug 29, 10:34 PM CDT	Tornado Warning	LIX	Hancock, Harrison, Pearl River	41 min
Aug 29, 11:45 PM CDT	Tornado Warning	LIX	Hancock, Harrison	31 min
Aug 30, 12:41 AM CDT	Tornado Warning	LIX	Harrison, Jackson	49 min
Aug 30, 2:47 AM CDT	Tornado Warning	LIX	Harrison, Jackson	47 min
Aug 30, 2:55 AM CDT	Tornado Warning	LIX	Jackson	65 min
Aug 30, 4:11 AM CDT	Flash Flood Warning	LIX	Harrison, Jackson	8 hr
Aug 30, 5:43 AM CDT	Flash Flood Warning	LIX	Pearl River	5 hr
Aug 30, 7:28 AM CDT	Tornado Warning	LIX	Jackson	22 min
Aug 30, 7:37 AM CDT	Tornado Warning	LIX	Harrison	23 min
Aug 30, 8:02 AM CDT	Tornado Warning	LIX	Harrison, Jackson	28 min
Aug 30, 9:30 AM CDT	Tornado Warning	LIX	Jackson	60 min
Aug 30, 11:17 AM CDT	Tornado Warning	LIX	Jackson	28 min
Aug 30, 12:33 PM CDT	Flash Flood Warning EmergencyConsiderable damage threat	LIX	Harrison, Jackson	3 hr
Aug 30, 3:51 PM CDT	Areal Flood Warning	LIX	Harrison, Jackson	30 hr

Nearby

Areal Flood Warnings in Mississippi, 2021 Areal Flood Warnings in Louisiana, 2021 Every areal flood warning 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.