Alert archive / Louisiana / Flash Flood Warnings in 2019

Flash Flood Warning 24, NWS Shreveport, LA

May 11, 20195 counties in Texas; 7 parishes in Louisiana

NWS Shreveport, LA issued this flash flood warning at May 11, 2019, 4:34 PM CDT for 5 counties in Texas; 7 parishes in Louisiana. It was in force for 2 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: May 11, 2019, 4:34 PM CDT (21:34 UTC)
Expired: May 11, 2019, 7:00 PM CDT
In force: 2 hr
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Flood severity: None

Counties Bienville Parish, LA, De Soto Parish, LA, Jackson Parish, LA, Natchitoches Parish, LA, Red River Parish, LA, Sabine Parish, LA, Winn Parish, LA, Angelina County, TX, Nacogdoches County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX

The radar

The Shreveport radar (KSHV), 77 km from the middle of the area, began a volume at 21:37 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

Lake Charles Mun, LA (KLCH), launched 12:00Z, 9.6 hours before the alert went out and 189 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: 326 J/kg
Mixed-layer CIN: -205 J/kg
Mixed-layer LCL: 793 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 205 m²/s²
0-3 km storm-relative helicity: 220 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning 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 flash flood warning went out at May 11, 3:40 PM CDT, 54 minutes earlier.

Area forecast discussion, May 11, 3:40 PM CDT, 54 minutes before

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Hazardous weather outlook, May 11, 11:49 AM CDT, 4 hours 45 minutes before

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In the hours before

Special weather statement, May 11, 1:54 PM CDT, 2 hours 40 minutes before

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Special weather statement, May 11, 2:26 PM CDT, 2 hours 8 minutes before

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Special weather statement, May 11, 2:54 PM CDT, 1 hour 40 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
May 11, 3:22 AM CDT	Special Weather Statement	SHV	Bowie	38 min
May 11, 9:38 AM CDT	Areal Flood Advisory	SHV	Camp, Gregg, Harrison, Marion, Morris, Rusk and 4 more	4 hr
May 11, 11:24 AM CDT	River Flood Warning	SHV	Gregg	44 hr
May 11, 1:54 PM CDT	Special Weather Statement	SHV	Cherokee	66 min
May 11, 2:26 PM CDT	Special Weather Statement	SHV	Panola, Rusk	34 min
May 11, 2:54 PM CDT	Special Weather Statement	SHV	Panola	36 min
May 11, 3:58 AM CDT	Special Weather Statement	SHV	Little River	32 min

Nearby

Flash Flood Warnings in Louisiana, 2019 Flash Flood Warnings in Texas, 2019 Every flash flood warning in 2019

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.