Alert archive / Alabama / Flash Flood Warnings in 2008

Flash Flood Warning 9, NWS Mobile, AL

April 18, 2008Washington County, Alabama; Greene County, Mississippi

NWS Mobile, AL issued this flash flood warning at Apr 18, 2008, 8:46 PM CDT for Washington County, Alabama; Greene County, Mississippi. It was in force for 3 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: Apr 18, 2008, 8:46 PM CDT (01:46 UTC)
Expired: Apr 18, 2008, 11:45 PM CDT
In force: 3 hr
Issued by: NWS Mobile, AL
Area: Storm-based polygon
Flood severity: None

Counties Washington County, AL, Greene County, MS

The radar

The Mobile radar (KMOB), 86 km from the middle of the area, began a volume at 01:48 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

Slidell Radar S, LA (KSIL), launched 00:00Z, 1.8 hours before the alert went out and 186 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: 695 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 712 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 396 m²/s²
0-3 km storm-relative helicity: 515 m²/s²
Significant tornado parameter: 1.8
Supercell composite: 9.2

Open this sounding in Storm Lab

The text

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

000 
WGUS54 KMOB 190147
FFWMOB
ALC129-MSC041-190445-
/O.NEW.KMOB.FF.W.0009.080419T0146Z-080419T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOBILE AL
846 PM CDT FRI APR 18 2008

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  GREENE COUNTY IN SOUTHEAST MISSISSIPPI...
  THIS INCLUDES THE CITY OF LEAKESVILLE...
  WASHINGTON COUNTY IN SOUTHWEST ALABAMA...
  THIS INCLUDES THE CITY OF CHATOM...

* UNTIL 1145 PM CDT

* AT 844 PM CDT...TRAINED WEATHER SPOTTERS REPORTED FLASH FLOODING   
FROM THUNDERSTORMS ALONG HIGHWAY 57 IN GREENE COUNTY. ADDITIONAL 
HEAVY RAINS CONTINUE TO MOVE ACROSS THESE AREAS AND ANOTHER 1 TO 2 
INCHES IS POSSIBLE THROUGH 1145 TONIGHT.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  WAGARVILLE...VINEGAR BEND...TOPTON...TOINETTE...TIBBIE...
  SUNFLOWER...SEABOARD...MCINTOSH...HAWTHORN...ESCATAWPA...DEER
  PARK...CORTELUOU AND ROUNSAVILLE

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

LAT...LON 3160 8807 3159 8805 3128 8795 3105 8878
      3134 8884 3144 8861 3143 8847 3150 8846
      3166 8809
TIME...MOT...LOC 0146Z 323DEG 0KT 3146 8808 3116 8875

$$

1 follow-up statement

000 
WGUS74 KMOB 190406
FFSMOB

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOBILE AL
1105 PM CDT FRI APR 18 2008

ALC129-MSC041-190445-
/O.CON.KMOB.FF.W.0009.000000T0000Z-080419T0445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WASHINGTON AL-GREENE MS-
1105 PM CDT FRI APR 18 2008

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1145 PM CDT FOR
GREENE AND WASHINGTON COUNTIES...

AT 1103 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT THE THUNDERSTORMS HAD MOVED OUT OF THE WARNED AREAS. HOWEVER 
RUNOFF WILL CONTINUE THROUGH 1145 PM THIS EVENING. THE WARNING WILL 
LIKELY BE ALLOWED TO EXPIRE AT THAT TIME UNLESS ADDITIONAL FLOODING 
REPORTS ARE RECEIVED.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO YELLOW
PINE...YARBO...SAINT STEPHENS...JORDAN...FRUITDALE...CHATOM...
BIGBEE...SAND HILL...NEELY...JONATHAN...BOTHWELL AND AVERA

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

A TORNADO WATCH REMAINS IN EFFECT UNTIL MIDNIGHT CDT SATURDAY MORNING
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA.

LAT...LON 3160 8807 3159 8805 3128 8795 3105 8878
      3134 8884 3144 8861 3143 8847 3150 8846
      3166 8809
TIME...MOT...LOC 0405Z 180DEG 0KT 3146 8808 3116 8875

$$

The office that day

Everything else NWS Mobile, AL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 18, 7:55 PM CDT	Tornado Warning	MOB	Washington	50 min
Apr 18, 8:39 PM CDT	Severe Thunderstorm Warning	MOB	Clarke, Washington	51 min
Apr 18, 9:16 PM CDT	Severe Thunderstorm Warning	MOB	Washington	44 min
Apr 18, 9:26 PM CDT	Severe Thunderstorm Warning	MOB	Clarke, Monroe, Washington	49 min
Apr 18, 10:12 PM CDT	Severe Thunderstorm Warning	MOB	Conecuh, Monroe	48 min
Apr 18, 10:35 PM CDT	Severe Thunderstorm Warning	MOB	Clarke, Conecuh, Monroe	40 min
Apr 18, 7:36 PM CDT	Tornado Warning	MOB	Greene	39 min

Nearby

Flash Flood Warnings in Alabama, 2008 Flash Flood Warnings in Mississippi, 2008 Every flash flood warning in 2008

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.