Alert archive / Louisiana / Flash Flood Warnings in 2017

Flash Flood Warning 39, NWS Shreveport, LA

August 30, 2017De Soto Parish, Natchitoches Parish, Red River Parish, Louisiana

NWS Shreveport, LA issued this flash flood warning at Aug 30, 2017, 11:36 AM CDT for De Soto Parish, Natchitoches Parish, Red River Parish, Louisiana. It was in force for 8 hr. 14 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
Aug 30, 2017, 11:36 AM CDT (16:36 UTC)
Expired
Aug 30, 2017, 8:00 PM CDT
In force
8 hr
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Flood severity
None

Counties De Soto Parish, LA, Natchitoches Parish, LA, Red River Parish, LA

The radar

The Ft Polk radar (KPOE), 70 km from the middle of the area, began a volume at 16:36 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
Aug 30, 1:59 PM CDTFLASH FLOOD5 S Martin, LABRUSHY CREEK ROAD CLOSED DUE TO HIGH WATER.
Aug 30, 2:00 PM CDTFLASH FLOOD6 Nw Powhatan, LALOUISIANA DEPT OF TRANSPORTATION REPORTS ROAD CLOSURE ON LA HWY 480 AT LOCK AND DAM #4.
Aug 30, 2:20 PM CDTFLASH FLOODNatchitoches, LACOOP OBSERVER REPORTS ROAD CLOSURES PER POLICE DEPT EAST 5TH ST @ BIENVILLE; EAST 5TH @ ROYAL; WATSON DRIVE @ SOUTH DR, LEDET @ KATELYN WILLIAMS AVE FROM BYRD AVE TO SALTER ST, STEVENS @ E 3RD; TEXAS @ UNDERPASS EAGLE, FAIRGROUNDS RD @ REBA, ST BREDA AV, ROWEN
Aug 30, 2:23 PM CDTFLASH FLOOD2 Nw Natchitoches, LACHINQUAPIN DRIVE OFF OF LA HWY 3191 IMPASSABLE DUE TO HIGH WATER.
Aug 30, 3:28 PM CDTFLASH FLOODNatchitoches, LAKSLA STORY REPORTS ROADS CLOSED IN NATCHITOCHES PARISH, NELSON RD NEAR MARTHAVILLE, EIGHT MILE LOOP IN OAK GROVE, STILES RD OFF OF COLLIER HILL RD NORTH OF CAMPTI, LONGLOIS HILL RD NEAR FLORA, JIM BELL RD NORTH OF CAMPTI, ROCKS CREEK RD NEAR MARTHAVILLE, CENTR
Aug 30, 4:00 PM CDTFLASH FLOOD5 Wsw Powhatan, LAHIGHWAY 485 ABOUT 0.5 MILES WEST OF I-49, AS WELL AS 2 MILES NORTH OF THE HIGHWAY 6 INTERSECTION, WAS CLOSED DUE TO FLOODING.
Aug 30, 4:30 PM CDTFLASH FLOOD3 Nnw Campti, LACOLLIER HILL ROAD WAS FLOODED AND CLOSED.
Aug 30, 4:30 PM CDTFLASH FLOOD4 Nne Robeline, LAHIGHWAY 1222 AND POSEY ROAD WAS FLOODED AND CLOSED.
Aug 30, 4:39 PM CDTFLASH FLOOD3 S South Mansfield, LAHUDSON DARBY ROAD WASHED OUT, DRAINAGE DITCH COLLAPSED PER DPSO.
Aug 30, 6:00 PM CDTFLASH FLOOD1 Sse Campti, LAHIGHWAY 71 IN CAMPTI WAS FLOODED AND CLOSED.
Aug 30, 7:09 PM CDTFLASH FLOOD7 Nne Campti, LAHIGHWAY 153 ABOUT 1 MILE NORTH OF HIGHWAY 9 NEAR THE CRESTON COMMUNITY WAS CLOSED DUE TO FLOODING.
Aug 30, 7:10 PM CDTFLASH FLOOD3 Sw Ashland, LALA HWY 155 AT RED NELSON IMPASSABLE DUE TO HIGH WATER. NATCHITOCHES SO FACEBOOK POST.
Aug 30, 8:00 PM CDTFLASH FLOOD3 S Ashland, LAHIGHWAY 153 NEAR RED NELSON ROAD JUST SOUTH OF ASHLAND WAS CLOSED DUE TO FLOODING.
Aug 30, 8:00 PM CDTFLASH FLOOD9 Sw Coushatta, LALOUISIANA DEPT OF TRANSPORTATION REPORTS ROAD CLOSURE ON LA HWY 177 AT CHEMARD LAKE BRIDGE 2 MILES SOUTH OF I-49.

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

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 4.6 hours before the alert went out and 96 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, Shreveport, LA at 12:00Z on 2017-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 76 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, Shreveport, LA at 12:00Z on 2017-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 182 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
76 J/kg
Mixed-layer CIN
-58 J/kg
Mixed-layer LCL
448 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
182 m²/s²
0-3 km storm-relative helicity
198 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

108 
WGUS54 KSHV 301636
FFWSHV
LAC031-069-081-301900-
/O.NEW.KSHV.FF.W.0039.170830T1636Z-170830T1900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
1136 AM CDT WED AUG 30 2017

The National Weather Service in Shreveport has issued a

* Flash Flood Warning for...
  Southern De Soto Parish in northwestern Louisiana...
  Red River Parish in northwestern Louisiana...
  Natchitoches Parish in northwestern Louisiana...

* Until 200 PM CDT

* At 1135 AM CDT, Doppler radar indicated heavy rain across the
  warned area. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Natchitoches, Mansfield, Coushatta, Logansport, Campti, Allen,
  Provencal, Natchez, Martin, Clarence, Goldonna, South Mansfield,
  Ashland, Edgefield, Robeline, Powhatan, Stanley, Carmel, Lake End
  and Kisatchie.

Additional rainfall amounts of two to three inches are possible in 
the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3136 9324 3154 9324 3154 9334 3171 9334
      3172 9344 3184 9344 3185 9388 3190 9390
      3201 9404 3217 9319 3215 9319 3215 9294
      3194 9287 3186 9290 3185 9295 3168 9297
      3162 9290 3160 9280 3152 9272 3135 9295

$$

05
1 follow-up statement
910 
WGUS54 KSHV 301845
FFWSHV
LAC031-069-081-310100-
/O.EXT.KSHV.FF.W.0039.000000T0000Z-170831T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
145 PM CDT WED AUG 30 2017

The National Weather Service in Shreveport has extended the

* Flash Flood Warning for...
  Southern De Soto Parish in northwestern Louisiana...
  Red River Parish in northwestern Louisiana...
  Natchitoches Parish in northwestern Louisiana...

* Until 800 PM CDT Wednesday

* At 144 PM CDT, Doppler radar indicated heavy rain across the warned
  area. Flash flooding will begin shortly.

* Some locations that will experience flooding include...
  Natchitoches, Mansfield, Coushatta, Logansport, Campti, Allen,
  Provencal, Natchez, Martin, Clarence, Goldonna, South Mansfield,
  Ashland, Edgefield, Robeline, Powhatan, Stanley, Carmel, Lake End
  and Kisatchie.

Additional rainfall amounts of two to three inches are possible in 
the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3136 9324 3154 9324 3154 9334 3171 9334
      3172 9344 3184 9344 3185 9388 3190 9390
      3201 9404 3217 9319 3215 9319 3215 9294
      3194 9287 3186 9290 3185 9295 3168 9297
      3162 9290 3160 9280 3152 9272 3135 9295

$$

05

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 29, 10:06 PM CDTLake Wind AdvisorySHVBienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more27 hr
Aug 30, 6:22 AM CDTAreal Flood AdvisorySHVBossier, Caddo3 hr
Aug 30, 6:52 AM CDTAreal Flood AdvisorySHVDe Soto, Natchitoches, Red River, Sabine3 hr
Aug 30, 10:09 AM CDTRiver Flood WarningSHVCaldwell, Grant, LaSalle, Winn8 days
Aug 30, 10:34 AM CDTFlash Flood WarningSHVSabine9 hr
Aug 30, 2:25 PM CDTFlash Flood WarningSHVBienville, Caldwell, Grant, Jackson, LaSalle, Winn6 hr

Nearby

Flash Flood Warnings in Louisiana, 2017Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.