Alert archive / Louisiana / Flash Flood Watches in 2017

Flash Flood Watch 8, NWS New Orleans, LA

June 29, 201713 parishes in Louisiana; Pearl River County, Mississippi

NWS New Orleans, LA issued this flash flood watch at Jun 29, 2017, 2:54 AM CDT for 13 parishes in Louisiana; Pearl River County, Mississippi. It took effect at Jun 29, 2017, 3:00 AM CDT. It was in force for 18 hr.

The area

The counties it named.

The facts

Issued: Jun 29, 2017, 2:54 AM CDT (07:54 UTC)
In effect from: Jun 29, 2017, 3:00 AM CDT
Expired: Jun 29, 2017, 9:20 PM CDT
In force: 18 hr
Issued by: NWS New Orleans, LA
Flood severity: None

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, Pearl River County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 7.9 hours before the alert went out and 105 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: 5 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 897 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -12 m²/s²
0-3 km storm-relative helicity: -7 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 flash flood watch 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 flash flood watch went out at Jun 29, 12:07 AM CDT, 2 hours 47 minutes earlier.

Area forecast discussion, Jun 29, 12:07 AM CDT, 2 hours 47 minutes before

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Hazardous weather outlook, Jun 28, 3:40 PM CDT, 11 hours 14 minutes before

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    <section class="card" role="status" aria-live="polite">
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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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
Jun 29, 6:55 AM CDT	Special Marine Warning	LIX		65 min
Jun 29, 7:31 AM CDT	Special Weather Statement	LIX	Livingston	29 min
Jun 29, 8:38 AM CDT	Special Marine Warning	LIX		97 min
Jun 29, 8:39 AM CDT	Special Marine Warning	LIX		2 hr
Jun 29, 9:22 AM CDT	Special Weather Statement	LIX	Assumption	53 min
Jun 29, 10:05 AM CDT	Special Weather Statement	LIX	Ascension, Assumption, Saint James, Saint John the Baptist	55 min
Jun 29, 11:42 AM CDT	Special Marine Warning	LIX		2 hr
Jun 29, 2:50 PM CDT	Special Marine Warning	LIX		55 min
Jun 29, 2:59 PM CDT	Special Marine Warning	LIX		2 hr
Jun 29, 3:03 PM CDT	Special Marine Warning	LIX		87 min
Jun 29, 4:06 PM CDT	Areal Flood Advisory	LIX	East Feliciana, Iberville, Pointe Coupee, West Baton Rouge, West Feliciana	114 min
Jun 29, 4:56 PM CDT	Special Marine Warning	LIX		64 min
Jun 29, 5:11 PM CDT	Special Marine Warning	LIX		64 min
Jun 29, 6:20 PM CDT	Special Marine Warning	LIX		55 min
Jun 29, 4:46 AM CDT	Special Weather Statement	LIX	Jackson	29 min
Jun 29, 10:16 AM CDT	River Flood Warning	LIX	Pearl River	53 hr
Jun 29, 10:16 AM CDT	River Flood Warning	LIX	Pearl River	52 hr
Jun 29, 10:19 AM CDT	River Flood Warning	LIX	Harrison	47 hr
Jun 29, 10:19 AM CDT	River Flood Warning	LIX	Harrison	40 hr
Jun 29, 2:45 PM CDT	Tornado Warning	LIX	Jackson	60 min
Jun 29, 3:47 PM CDT	Special Weather Statement	LIX	Jackson	28 min
Jun 29, 4:32 PM CDT	Flash Flood Warning	LIX	Harrison, Jackson	3 hr

Nearby

Flash Flood Watches in Louisiana, 2017 Flash Flood Watches in Mississippi, 2017 Every flash flood watch in 2017

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.