Alert archive / Texas / Flash Flood Warnings in 2017

Flash Flood Warning 49, NWS Lake Charles, LA

August 7, 2017Jefferson County, Texas

NWS Lake Charles, LA issued this flash flood warning at Aug 7, 2017, 2:40 PM CDT for Jefferson County, Texas. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 7, 2017, 2:40 PM CDT (19:40 UTC)
Expired
Aug 7, 2017, 4:45 PM CDT
In force
2 hr
Issued by
NWS Lake Charles, LA
Area
Storm-based polygon
Flood severity
None

County Jefferson County, TX

The radar

The Lake Charles radar (KLCH), 101 km from the middle of the area, began a volume at 19:41 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.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 7.7 hours before the alert went out and 102 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, Lake Charles Mun, LA at 12:00Z on 2017-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1620 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 12:00Z on 2017-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.1939Sfc1 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
1620 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
946 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
107 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.1

Open this sounding in Storm Lab

The text

As transmitted.

554 
WGUS54 KLCH 071940
FFWLCH
TXC245-072145-
/O.NEW.KLCH.FF.W.0049.170807T1940Z-170807T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Lake Charles LA
240 PM CDT MON AUG 7 2017

The National Weather Service in Lake Charles has issued a

* Flash Flood Warning for...
  Northwestern Jefferson County in southeastern Texas...

* Until 445 PM CDT

* At 238 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. 6 to 8 inches of rain have 
  fallen over the last several hours with more thunderstorms moving 
  into the area. Continued flash flooding is expected.

* Some locations that will experience flooding include...
  Beaumont, Nome, Bevil Oaks and China. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3011 9435 3012 9430 3014 9428 3016 9428
      3017 9427 3017 9424 3019 9421 3018 9419
      3019 9418 3017 9417 3016 9412 3014 9410
      3001 9419 2991 9436 3001 9445 3003 9444

$$

RACKLEY

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 10:58 AM CDTAreal Flood AdvisoryLCHJefferson2 hr
Aug 7, 12:11 PM CDTFlash Flood WarningLCHJefferson2 hr

Nearby

Flash Flood Warnings in Texas, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.