Alert archive / Louisiana / Flash Flood Watches in 2013

Flash Flood Watch 2, NWS New Orleans, LA

January 12, 201312 parishes in Louisiana; 4 counties in Mississippi

NWS New Orleans, LA issued this flash flood watch at Jan 12, 2013, 3:24 PM CST for 12 parishes in Louisiana; 4 counties in Mississippi. It took effect at Jan 13, 2013, 1:00 AM CST. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Jan 12, 2013, 3:24 PM CST (21:24 UTC)
In effect from: Jan 13, 2013, 1:00 AM CST
Expired: Jan 13, 2013, 4:23 AM CST
In force: 3 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 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, Pike County, MS, Walthall County, MS, Wilkinson County, MS

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 9.4 hours before the alert went out and 198 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: 308 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 484 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 166 m²/s²
0-3 km storm-relative helicity: 254 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.4

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 Jan 12, 11:41 AM CST, 3 hours 43 minutes earlier.

Area forecast discussion, Jan 12, 11:41 AM CST, 3 hours 43 minutes before

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Hazardous weather outlook, Jan 12, 1:46 PM CST, 1 hour 38 minutes before

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In the hours before

Special weather statement, Jan 12, 10:38 AM CST, 4 hours 46 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
Jan 12, 9:05 AM CST	Dense Fog Advisory	LIX	Assumption, Saint Bernard, Saint James, Saint John the Baptist	55 min
Jan 12, 9:18 AM CST	Marine Dense Fog Advisory	LIX		3 hr
Jan 12, 3:16 PM CST	Marine Dense Fog Advisory	LIX		17 hr
Jan 12, 3:34 PM CST	Dense Fog Advisory	LIX	Assumption, Saint Bernard, Saint James, Saint John the Baptist, Washington	17 hr
Jan 12, 12:35 AM CST	River Flood Warning	LIX	Pearl River	4 days

Nearby

Flash Flood Watches in Louisiana, 2013 Flash Flood Watches in Mississippi, 2013 Every flash flood watch in 2013

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.