Alert archive / Alabama / Flash Flood Warnings in 2018

Flash Flood Warning 23, NWS Mobile, AL

September 5, 2018Choctaw County, Clarke County, Alabama

NWS Mobile, AL issued this flash flood warning at Sep 5, 2018, 4:30 AM CDT for Choctaw County, Clarke County, Alabama. It was in force for 6 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
Sep 5, 2018, 4:30 AM CDT (09:30 UTC)
Expired
Sep 5, 2018, 10:30 AM CDT
In force
6 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

Counties Choctaw County, AL, Clarke County, AL

The radar

The Mobile radar (KMOB), 157 km from the middle of the area, began a volume at 09:33 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
Sep 5, 9:46 AM CDTFLASH FLOOD2 W Morvin, ALBUXTON CHAPEL RD CLOSED DUE TO A WASHOUT FROM FLOODING.
Sep 5, 10:00 AM CDTFLASH FLOODChoctaw City, ALCOTTONWOOD RD (COUNTY RD 37) IS CLOSED DUE TO A WASH OUT FROM FLOODING.
Sep 5, 10:22 AM CDTFLASH FLOOD1 Ese Grove Hill, ALEMERGENCY MANAGER REPORTS FLOODING AT WILSON HALL MIDDLE SCHOOL. FLOOD WATERS ENTERING THE SCHOOL LIBRARY.

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

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 9.5 hours before the alert went out and 170 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, Birmingham, AL at 00:00Z on 2018-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 438 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, Birmingham, AL at 00:00Z on 2018-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 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
438 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
1319 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

571 
WGUS54 KMOB 050930
FFWMOB
ALC023-025-051530-
/O.NEW.KMOB.FF.W.0023.180905T0930Z-180905T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
430 AM CDT WED SEP 5 2018

The National Weather Service in Mobile has issued a

* Flash Flood Warning for...
  Choctaw County in southwestern Alabama...
  Northwestern Clarke County in southwestern Alabama...

* Until 1030 AM CDT Wednesday.

* At 429 AM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have
  already fallen. Flash flooding is expected to begin shortly.

Additional rainfall amounts of two and four inches are possible in 
the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 3231 8793 3228 8793 3230 8794 3230 8798
      3228 8802 3218 8801 3215 8802 3214 8804
      3209 8804 3206 8807 3207 8810 3206 8812
      3201 8812 3199 8807 3199 8781 3168 8772
      3168 8808 3170 8809 3170 8823 3231 8839

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 4, 8:24 PM CDTFlash Flood WarningMOBBaldwin12 hr
Sep 4, 8:24 PM CDTRiver Flood WarningMOBBaldwin40 hr
Sep 4, 8:31 PM CDTRiver Flood WarningMOBBaldwin4 days
Sep 4, 8:32 PM CDTRiver Flood WarningMOBBaldwin70 hr
Sep 4, 9:00 PM CDTFlash Flood WarningMOBMobile6 hr
Sep 4, 10:45 PM CDTFlash Flood WarningMOBBaldwin, Escambia12 hr
Sep 5, 12:53 AM CDTTornado WarningMOBBaldwin25 min
Sep 5, 2:06 AM CDTFlash Flood WarningMOBClarke, Monroe, Washington6 hr
Sep 5, 3:19 AM CDTSpecial Marine WarningMOB26 min
Sep 5, 3:32 AM CDTSpecial Marine WarningMOB28 min
Sep 5, 4:57 AM CDTSmall Craft AdvisoryMOB5 hr
Sep 5, 5:15 AM CDTCoastal Flood AdvisoryMOBBaldwin, Mobile9 hr
Sep 5, 5:15 AM CDTHigh Surf AdvisoryMOBBaldwin, Mobile9 hr
Sep 5, 7:54 AM CDTFlash Flood WarningMOBBaldwin, Clarke, Conecuh, Escambia, Mobile, Monroe and 1 more6 hr
Sep 5, 8:06 AM CDTFlash Flood WarningMOBBaldwin, Clarke, Monroe, Washington6 hr
Sep 5, 9:06 AM CDTFlash Flood WarningMOBClarke, Conecuh, Monroe, Wilcox6 hr
Sep 5, 9:35 AM CDTSpecial Marine WarningMOB115 min
Sep 5, 10:25 AM CDTFlash Flood WarningMOBChoctaw, Clarke5 hr
Sep 5, 12:53 PM CDTAreal Flood AdvisoryMOBMobile52 min
Sep 5, 1:50 PM CDTAreal Flood WarningMOBBaldwin, Escambia6 hr

Nearby

Flash Flood Warnings in Alabama, 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.