Alert archive / Alabama / Flash Flood Warnings in 2017

Flash Flood Warning 11, NWS Mobile, AL

April 30, 2017Mobile County, Alabama

NWS Mobile, AL issued this flash flood warning at Apr 30, 2017, 8:07 PM CDT for Mobile County, Alabama. It was in force for 6 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 30, 2017, 8:07 PM CDT (01:07 UTC)
Expired
May 1, 2017, 2:00 AM CDT
In force
6 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

County Mobile County, AL

The radar

The Mobile radar (KMOB), 34 km from the middle of the area, began a volume at 01:11 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, 1.1 hours before the alert went out and 132 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, Slidell Radar S, LA at 00:00Z on 2017-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 569 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, Slidell Radar S, LA at 00:00Z on 2017-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 211 square meters per square second.19395878Sfc1 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
569 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
531 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
211 m²/s²
0-3 km storm-relative helicity
267 m²/s²
Significant tornado parameter
1.1
Supercell composite
7.8

Open this sounding in Storm Lab

The text

As transmitted.

643 
WGUS54 KMOB 010107
FFWMOB
ALC097-010700-
/O.NEW.KMOB.FF.W.0011.170501T0107Z-170501T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
807 PM CDT SUN APR 30 2017

The National Weather Service in Mobile has issued a

* Flash Flood Warning for...
  Southwestern Mobile County in southwestern Alabama...

* Until 200 AM CDT

* At 806 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have
  already fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Tillmans Corner, Theodore, Grand Bay, Bayou La Batre, Central
  Dauphin Island, Coden, Fort Gaines, Alabama Port and I10 And I65.

Additional rainfall amounts of 2 to 4 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.

&&

LAT...LON 3022 8838 3033 8840 3035 8839 3038 8841
      3039 8841 3038 8840 3067 8841 3063 8804
      3022 8807

$$
1 follow-up statement
942 
WGUS74 KMOB 010341
FFSMOB

Flash Flood Statement
National Weather Service Mobile AL
1041 PM CDT SUN APR 30 2017

ALC097-010700-
/O.CON.KMOB.FF.W.0011.000000T0000Z-170501T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mobile AL-
1041 PM CDT SUN APR 30 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 200 AM CDT FOR
SOUTHWESTERN MOBILE COUNTY...

At 1032 PM CDT, Doppler radar indicated thunderstorms producing 
heavy rain across the warned area. Per latest observations, up to 4 
inches of rain have fallen along a line extending from the Dog River 
southwest to Bayou La Batre, with 2 to 3 inches having fallen 
elsewhere within the warned area. Flash flooding is ongoing or 
expected to begin shortly.

Some locations that will experience flooding include...
Tillmans Corner, Theodore, Grand Bay, Bayou La Batre, Central Dauphin
Island, Coden, Fort Gaines, Alabama Port and I10 And I65.

Additional rainfall amounts of 1 to 2 inches are possible over the 
next couple hours as storms continue to form over the northern Gulf 
and move north into the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3022 8838 3033 8840 3035 8839 3038 8841
      3039 8841 3038 8840 3067 8841 3063 8804
      3022 8807

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 30, 7:11 PM CDTSpecial Weather StatementMOBButler, Covington, Crenshaw64 min
Apr 30, 7:23 PM CDTAreal Flood AdvisoryMOBMobile3 hr
Apr 30, 7:39 PM CDTSpecial Marine WarningMOB66 min
Apr 30, 8:29 PM CDTAreal Flood AdvisoryMOBButler, Covington, Crenshaw3 hr
Apr 30, 8:35 PM CDTSpecial Marine WarningMOB85 min
Apr 30, 8:36 PM CDTHigh Wind WarningMOBBaldwin, Mobile3 hr
Apr 30, 9:13 PM CDTFlash Flood WarningMOBBaldwin, Mobile6 hr
Apr 30, 9:47 PM CDTSpecial Marine WarningMOB88 min
Apr 30, 10:46 PM CDTSpecial Weather StatementMOBChoctaw59 min
Apr 30, 10:54 PM CDTSpecial Weather StatementMOBBaldwin36 min
Apr 30, 10:58 PM CDTSpecial Marine WarningMOB92 min
Apr 30, 11:02 PM CDTSevere Thunderstorm WarningMOBChoctaw43 min
Apr 30, 11:06 PM CDTSpecial Marine WarningMOB54 min
Apr 30, 11:13 PM CDTWind AdvisoryMOBBaldwin, Butler, Conecuh, Covington, Crenshaw, Escambia and 2 more8 hr
Apr 30, 11:31 PM CDTSpecial Marine WarningMOB59 min
Apr 30, 11:41 PM CDTSevere Thunderstorm WarningMOBChoctaw, Clarke49 min
Apr 30, 11:53 PM CDTSpecial Weather StatementMOBClarke, Washington67 min
Apr 30, 11:55 PM CDTSpecial Marine WarningMOB95 min
May 1, 12:13 AM CDTSevere Thunderstorm WarningMOBClarke, Wilcox47 min
May 1, 12:23 AM CDTSpecial Marine WarningMOB67 min
May 1, 12:56 AM CDTSpecial Weather StatementMOBClarke, Washington49 min
May 1, 1:23 AM CDTSpecial Marine WarningMOB97 min
May 1, 1:25 AM CDTSpecial Marine WarningMOB95 min
May 1, 2:01 AM CDTSpecial Weather StatementMOBMonroe44 min
May 1, 2:56 AM CDTSpecial Marine WarningMOB64 min
May 1, 2:58 AM CDTSpecial Marine WarningMOB2 hr
May 1, 3:31 AM CDTSpecial Weather StatementMOBEscambia44 min
May 1, 3:47 AM CDTSpecial Weather StatementMOBBaldwin43 min
May 1, 3:53 AM CDTSpecial Marine WarningMOB2 hr
May 1, 5:08 AM CDTSpecial Marine WarningMOB112 min
May 1, 5:12 AM CDTRip Current StatementMOBBaldwin, Mobile20 hr
May 1, 5:25 AM CDTSpecial Weather StatementMOBCovington50 min
May 1, 5:48 AM CDTSpecial Weather StatementMOBCrenshaw42 min
May 1, 6:01 AM CDTSpecial Marine WarningMOB59 min
May 1, 6:01 AM CDTSevere Thunderstorm WarningMOBCovington, Crenshaw17 min
May 1, 6:52 AM CDTSpecial Weather StatementMOBCovington38 min
May 1, 7:00 AM CDTSpecial Marine WarningMOB2 hr

Nearby

Flash Flood Warnings in Alabama, 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.