Alert archive / Louisiana / Flash Flood Warnings in 2012

Flash Flood Warning 20, NWS Jackson, MS

March 21, 2012Franklin Parish, Richland Parish, Louisiana

NWS Jackson, MS issued this flash flood warning at Mar 21, 2012, 9:49 AM CDT for Franklin Parish, Richland Parish, Louisiana. It was in force for 116 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Mar 21, 2012, 9:49 AM CDT (14:49 UTC)
Expired
Mar 21, 2012, 11:45 AM CDT
In force
116 min
Issued by
NWS Jackson, MS
Area
Storm-based polygon
Flood severity
None

Counties Franklin Parish, LA, Richland Parish, LA

The radar

The Jackson/Brandon,MS radar (KDGX), 169 km from the middle of the area, began a volume at 14:49 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.

What was reported inside it

TimeReportWhereRemark
Mar 21, 11:30 AM CDTFLASH FLOODRayville, LANUMEROUS ROADS FLOODED AROUND RICHLAND PARISH

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 2.8 hours before the alert went out and 160 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-pSkew-T log-p diagram, Jackson, MS at 12:00Z on 2012-03-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 143 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Jackson, MS at 12:00Z on 2012-03-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 239 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
143 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
559 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
239 m²/s²
0-3 km storm-relative helicity
239 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

498 
WGUS54 KJAN 211449
FFWJAN
LAC041-083-211645-
/O.NEW.KJAN.FF.W.0020.120321T1449Z-120321T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE JACKSON MS
949 AM CDT WED MAR 21 2012

THE NATIONAL WEATHER SERVICE IN JACKSON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  FRANKLIN PARISH IN NORTHEAST LOUISIANA...
  THIS INCLUDES THE CITY OF WINNSBORO...
  CENTRAL RICHLAND PARISH IN NORTHEAST LOUISIANA...
  THIS INCLUDES THE CITIES OF...START...RAYVILLE...MANGHAM...

* UNTIL 1145 AM CDT

* AT 947 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED   
  THUNDERSTORMS PRODUCING VERY HEAVY RAIN SCROSS THE WARNED AREA.
  RADAR ESTIMATED THAT ONE AND A HALF TO THREE INCHES OF RAIN HAD 
  FALLEN OVER THE WARNED AREA THIS MORNING. ADDITIONAL RAINFALL OF
  1 TO 3 INCHES OVER THE NEXT TWO HOURS WILL LIKELY CAUSE FLOODING
  OF LOW LYING AND POOR DRAINAGE AREAS...AS WELL AS SMALL BAYOUS AND
  CREEKS.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO HOLLY
  RIDGE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE WATER COVERS THE ROADWAY. WHEN ENCOUNTERING FLOODED ROADS
MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3252 9185 3252 9184 3254 9184 3257 9181
      3256 9175 3259 9173 3261 9162 3198 9156
      3194 9183 3229 9191

$$

The office that day

Everything else NWS Jackson, MS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 21, 7:27 AM CDTSpecial Weather StatementJANCatahoula28 min
Mar 21, 7:29 AM CDTTornado WarningJANCatahoula, Concordia46 min
Mar 21, 8:42 AM CDTSpecial Weather StatementJANCatahoula28 min
Mar 21, 9:03 AM CDTTornado WarningJANCatahoula, Franklin42 min
Mar 21, 9:38 AM CDTSevere Thunderstorm WarningJANRichland41 min
Mar 21, 9:51 AM CDTSpecial Weather StatementJANTensas44 min
Mar 21, 10:20 AM CDTAreal Flood WarningJANConcordia3 hr
Mar 21, 10:48 AM CDTSevere Thunderstorm WarningJANMadison57 min
Mar 21, 12:47 PM CDTAreal Flood WarningJANEast Carroll, Franklin, Madison, Morehouse, Richland, West Carroll12 hr

Nearby

Flash Flood Warnings in Louisiana, 2012Every flash flood warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.