Alert archive / Texas / Areal Flood Advisories in 2021

Areal Flood Advisory 2, NWS Shreveport, LA

April 7, 20214 counties in Texas

NWS Shreveport, LA issued this areal flood advisory at Apr 7, 2021, 6:25 PM CDT for 4 counties in Texas. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Apr 7, 2021, 6:25 PM CDT (23:25 UTC)
Expired: Apr 7, 2021, 9:30 PM CDT
In force: 3 hr
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

Counties Angelina County, TX, Nacogdoches County, TX, Sabine County, TX, San Augustine County, TX

The radar

The Shreveport radar (KSHV), 125 km from the middle of the area, began a volume at 23:24 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

Shreveport, LA (KSHV), launched 12:00Z, 11.4 hours before the alert went out and 131 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: 532 J/kg
Mixed-layer CIN: -229 J/kg
Mixed-layer LCL: 506 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 267 m²/s²
0-3 km storm-relative helicity: 433 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Shreveport, LA wrote its last area forecast discussion before this areal flood advisory went out at Apr 7, 5:23 PM CDT, 1 hour 2 minutes earlier.

Area forecast discussion, Apr 7, 5:23 PM CDT, 1 hour 2 minutes before

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Hazardous weather outlook, Apr 7, 3:24 AM CDT, 15 hours 1 minute before

Hazardous Weather Outlook
National Weather Service Shreveport LA
324 AM CDT Wed Apr 7 2021

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-
TXZ096-097-108>112-124>126-136>138-149>153-165>167-081200-
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Union-Caddo-Bossier-Webster-Claiborne-Lincoln-De Soto-
Red River-Bienville-Jackson-Ouachita-Sabine-Natchitoches-Winn-
Grant-Caldwell-La Salle-McCurtain-Bowie-Franklin-Titus-Camp-
Morris-Cass-Wood-Upshur-Marion-Smith-Gregg-Harrison-Cherokee-Rusk-
Panola-Nacogdoches-Shelby-Angelina-San Augustine-
324 AM CDT Wed Apr 7 2021

This Hazardous Weather Outlook is for portions of south central
Arkansas, southwest Arkansas, north central Louisiana, northwest
Louisiana, southeast Oklahoma, east Texas and northeast Texas.

.DAY ONE...Today and Tonight...

Strong to severe thunderstorms will become likely later today
through this evening across at least the eastern half of the Four
State Region which would include all of Southern Arkansas and all
of Northern Louisiana. A more conditional threat exists across
Southeast Oklahoma and Northeast Texas. Conditions will be
conducive for damaging wind gusts, large hail and isolated
tornadoes this afternoon through this evening where severe
thunderstorms develop. The severe weather threat should end across
Northeast Louisiana after midnight.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday...

After a relatively quiet day on Thursday, more severe
thunderstorms are back in the forecast for Friday Afternoon
through Friday Evening once again. Look for the possibility of
very large hail, damaging thunderstorm wind gusts and isolated
tornadoes once again during this time frame along and ahead of a
cold front that should move through the region late Friday Night
into early Saturday.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel...amateur radio
operators...and storm spotters will likely be needed this
afternoon into this evening. Please relay any information about
observed severe weather to the NWS while following all local,
state, and CDC guidelines.

13

In the hours before

Special weather statement, Apr 7, 4:50 PM CDT, 1 hour 35 minutes before

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Local storm report, Apr 7, 5:00 PM CDT, 1 hour 25 minutes before

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Local storm report, Apr 7, 5:25 PM CDT, 1 hour before

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Local storm report, Apr 7, 5:53 PM CDT, 32 minutes before

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Local storm report, Apr 7, 5:58 PM CDT, 27 minutes before

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Local storm report, Apr 7, 6:04 PM CDT, 21 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 7, 1:22 PM CDT	Severe Thunderstorm Warning	SHV	Sabine, San Augustine, Shelby	38 min
Apr 7, 1:32 PM CDT	Special Weather Statement	SHV	Camp, Upshur	43 min
Apr 7, 2:12 PM CDT	Severe Thunderstorm Warning	SHV	Gregg, Harrison, Marion, Upshur	63 min
Apr 7, 2:30 PM CDT	Special Weather Statement	SHV	Cherokee	45 min
Apr 7, 4:02 PM CDT	Special Weather Statement	SHV	Angelina, San Augustine, Shelby	43 min
Apr 7, 4:09 PM CDT	Severe Thunderstorm Warning	SHV	Angelina, Nacogdoches, Sabine, San Augustine	51 min
Apr 7, 4:50 PM CDT	Special Weather Statement	SHV	San Augustine	40 min
Apr 7, 4:58 PM CDT	Severe Thunderstorm Warning	SHV	Angelina, Nacogdoches, Sabine, San Augustine	62 min
Apr 7, 5:36 PM CDT	Severe Thunderstorm Warning	SHV	Sabine	39 min
Apr 7, 1:50 PM CDT	Special Weather Statement	SHV	De Soto	40 min
Apr 7, 3:12 PM CDT	Special Weather Statement	SHV	Lincoln, Union	48 min
Apr 7, 3:21 PM CDT	Special Weather Statement	SHV	Claiborne, Webster	39 min
Apr 7, 3:56 PM CDT	Special Weather Statement	SHV	De Soto	49 min
Apr 7, 4:09 PM CDT	Special Weather Statement	SHV	Claiborne	51 min
Apr 7, 4:20 PM CDT	Tornado Warning	SHV	Bienville, Bossier, Caddo, De Soto, Red River	40 min
Apr 7, 4:31 PM CDT	Tornado Warning	SHV	Bienville, Bossier, Caddo, Claiborne, Webster	19 min
Apr 7, 4:52 PM CDT	Tornado Warning	SHV	Bienville, Red River	25 min
Apr 7, 5:16 PM CDT	Tornado Warning	SHV	Bienville, Claiborne, Jackson, Lincoln, Webster	14 min
Apr 7, 6:38 PM CDT	Tornado Warning	SHV	Jackson, Lincoln, Ouachita, Union	52 min

Nearby

Areal Flood Advisories in Texas, 2021 Every areal flood 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.