Alert archive / Louisiana / Flash Flood Warnings in 2018

Flash Flood Warning 3, NWS Jackson, MS

February 21, 2018Catahoula Parish, Franklin Parish, Tensas Parish, Louisiana

NWS Jackson, MS issued this flash flood warning at Feb 21, 2018, 1:52 PM CST for Catahoula Parish, Franklin Parish, Tensas Parish, Louisiana. It was in force for 3 hr. 3 reports 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
Feb 21, 2018, 1:52 PM CST (19:52 UTC)
Expired
Feb 21, 2018, 4:45 PM CST
In force
3 hr
Issued by
NWS Jackson, MS
Area
Storm-based polygon
Flood severity
None

Counties Catahoula Parish, LA, Franklin Parish, LA, Tensas Parish, LA

The radar

The Ft Polk radar (KPOE), 154 km from the middle of the area, began a volume at 19:56 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
Feb 21, 2:30 PM CSTFLASH FLOODWisner, LATOWN POLICE REPORTS FLASH FLOODING ON ROADWAYS NEAR WISNER.
Feb 21, 3:00 PM CSTFLASH FLOOD1 N Winnsboro, LAWATER REPORTED IN 3 BUSINESSES ON FAIR AVENUE IN WINNSBORO.
Feb 21, 3:00 PM CSTFLASH FLOOD1 Ssw Wisner, LAEMERGENCY MANAGER REPORTS LOCALIZED FLASH FLOODING OVER THE NORTHERN PORTIONS OF THE PARISH. SOME DRIVEWAYS ARE UNDER WATER, ALONG WITH A PARISH ROAD.

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, 7.9 hours before the alert went out and 159 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 2018-02-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 363 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 2018-02-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 213 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
363 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
622 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
213 m²/s²
0-3 km storm-relative helicity
208 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.5

Open this sounding in Storm Lab

The text

As transmitted.

682 
WGUS54 KJAN 211952
FFWJAN
LAC025-041-107-212245-
/O.NEW.KJAN.FF.W.0003.180221T1952Z-180221T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Jackson MS
152 PM CST WED FEB 21 2018

The National Weather Service in Jackson has issued a

* Flash Flood Warning for...
  Northwestern Tensas Parish in northeastern Louisiana...
  Northern Catahoula Parish in northeastern Louisiana...
  Franklin Parish in northeastern Louisiana...

* Until 445 PM CST

* At 152 PM CST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to two to three inches of 
  rain have already fallen. Flash flooding is expected to begin 
  shortly.

* Some locations that will experience flooding include...
  Winnsboro, Wisner, Rosefield, Aimwell, Manifest, Sherwood, Wallace
  Ridge, Jigger, Archie, Newlight, Liddieville, Enterprise, Cooter
  Point, Sicily Island, Gilbert and Harrisonburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 3193 9201 3193 9190 3203 9190 3207 9193
      3209 9187 3214 9190 3217 9188 3224 9155
      3226 9154 3223 9151 3221 9155 3220 9132
      3201 9129 3154 9201

$$

TW

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 21, 12:48 PM CSTSevere Thunderstorm WarningJANCatahoula, Concordia, Franklin, Richland42 min
Feb 21, 1:00 PM CSTRiver Flood WarningJANEast Carroll32 days
Feb 21, 1:00 PM CSTRiver Flood WarningJANMadison, Tensas35 days
Feb 21, 1:00 PM CSTRiver Flood WarningJANConcordia79 days
Feb 21, 1:28 PM CSTSevere Thunderstorm WarningJANCatahoula, Franklin, Tensas62 min
Feb 21, 2:28 PM CSTSevere Thunderstorm WarningJANFranklin, Tensas32 min
Feb 21, 2:39 PM CSTSpecial Weather StatementJANMadison51 min
Feb 21, 2:53 PM CSTSevere Thunderstorm WarningJANMadison36 min

Nearby

Flash Flood Warnings in Louisiana, 2018Every flash flood warning in 2018

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.