Alert archive / Alabama / Flash Flood Warnings in 2017

Flash Flood Warning 14, NWS Mobile, AL

May 20, 2017Mobile County, Alabama

NWS Mobile, AL issued this flash flood warning at May 20, 2017, 7:38 PM CDT for Mobile County, Alabama. It was in force for 6 hr. 5 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
May 20, 2017, 7:38 PM CDT (00:38 UTC)
Expired
May 21, 2017, 1:30 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), 27 km from the middle of the area, began a volume at 00:39 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
May 20, 7:45 PM CDTFLASH FLOODSaraland, ALSTREET FLOODING IN SARALAND, AL. POLICE HAVE BLOCKED OFF SOME LOCAL ROADS.
May 20, 8:25 PM CDTFLASH FLOODN Saraland, ALHIGHWAY 43 AT SHELTON BEACH ROAD IS UNDERWATER AND BLOCKED OFF.
May 20, 8:30 PM CDTFLASH FLOODSaraland, ALSARALAND PD REPORTS THAT NUMEROUS STREETS WERE FLOODED AND RENDERED IMPASSABLE AND THAT SOME HOMES WERE ALSO FLOODED. SOME SARALAND RESIDENTS WERE ALSO EVACUATED DUE TO FLASH FLOODING.
May 20, 9:40 PM CDTFLASH FLOODSaraland, ALSTREETING FLOODING IN THE COMMUNITY OF SARALAND CONTINUES. PICTURE VIA SOICAL MEDIA.
May 20, 10:00 PM CDTFLASH FLOOD1 Ne I65 And Al 158, ALINTERNATIONAL BLVD BLOCKED OFF DUE TO FLOODING IN SARALAND.

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

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 0.6 hours before the alert went out and 173 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 2017-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3071 joules per kilogram.LCLEL10008507005003002001001 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, Slidell Radar S, LA at 00:00Z on 2017-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
3071 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
745 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

681 
WGUS54 KMOB 210038
FFWMOB
ALC097-210630-
/O.NEW.KMOB.FF.W.0014.170521T0038Z-170521T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
738 PM CDT SAT MAY 20 2017

The National Weather Service in Mobile has issued a

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

* Until 130 AM CDT

* At 735 PM CDT, Doppler radar indicated thunderstorms producing 
  very heavy rain across the warned area. Radar estimates that 2 to 
  4 inches inches of rain have fallen across much of the warned 
  area, with the heaviest amounts near Chunchula, Saraland and 
  Prichard. Additional thunderstorms producing heavy rain will 
  continue to move in over the next couple of hours. Flash flooding 
  is expected to begin shortly.

* Some locations that will experience flooding include...
  Prichard, Saraland, Chickasaw, Satsuma, Creola, Chunchula,
  Gulfcrest, Axis, Semmes, Tanner Williams, I65 And I165, Wilmer and
  I65 And AL 158.

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 3071 8841 3104 8842 3099 8787 3087 8790
      3087 8791 3094 8793 3089 8793 3089 8798
      3085 8792 3086 8791 3078 8794 3081 8794
      3082 8796 3077 8802 3077 8794 3073 8801
      3070 8799

$$
1 follow-up statement
486 
WGUS74 KMOB 210244
FFSMOB

Flash Flood Statement
National Weather Service Mobile AL
944 PM CDT SAT MAY 20 2017

ALC097-210630-
/O.CON.KMOB.FF.W.0014.000000T0000Z-170521T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mobile AL-
944 PM CDT SAT MAY 20 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 AM CDT FOR
NORTHERN MOBILE COUNTY...

At 940 PM CDT, local media reported flooding continuing in the 
community of Saraland. 

At 825 PM CDT, the Department of Highways reported flash flooding at 
U.S. Highway 43 and Shelton Beach Road in Saraland. There have also 
been preliminary reports of water reaching some houses in the 
Saraland community. 

At 940 PM CDT, Doppler radar indicated that heavier rains were 
starting to move east of the warned area. However, radar estimates 
that 3 to 6 inches of rain with locally higher amounts have fallen 
in the warned area this evening. Flash flooding remains imminent. 

Some locations that will continue to experience flooding include...
Prichard, Saraland, Chickasaw, Satsuma, Creola, Chunchula, Gulfcrest,
Axis, Semmes, Tanner Williams, I65 And I165, Wilmer and I65 And AL
158.

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 3071 8841 3104 8842 3099 8787 3087 8790
      3087 8791 3094 8793 3089 8793 3089 8798
      3085 8792 3086 8791 3078 8794 3081 8794
      3082 8796 3077 8802 3077 8794 3073 8801
      3070 8799

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 7:06 PM CDTAreal Flood AdvisoryMOBMobile3 hr
May 20, 7:19 PM CDTSpecial Weather StatementMOBMobile41 min
May 20, 7:46 PM CDTSpecial Weather StatementMOBMobile44 min
May 20, 8:09 PM CDTSpecial Weather StatementMOBBaldwin, Mobile51 min
May 20, 8:12 PM CDTSpecial Weather StatementMOBBaldwin48 min
May 20, 8:17 PM CDTSpecial Marine WarningMOB88 min
May 20, 8:21 PM CDTSevere Thunderstorm WarningMOBMobile39 min
May 20, 8:25 PM CDTFlash Flood WarningMOBMobile6 hr
May 20, 8:56 PM CDTFlash Flood WatchMOBBaldwin, Escambia, Mobile7 hr
May 20, 9:02 PM CDTFlash Flood WarningMOBBaldwin, Escambia6 hr
May 20, 9:07 PM CDTSpecial Weather StatementMOBBaldwin, Escambia53 min
May 20, 9:23 PM CDTSpecial Marine WarningMOB52 min
May 20, 9:26 PM CDTSpecial Marine WarningMOB2 hr
May 20, 10:21 PM CDTAreal Flood AdvisoryMOBBaldwin, Conecuh, Covington, Escambia3 hr
May 20, 10:25 PM CDTSpecial Weather StatementMOBCovington65 min
May 20, 10:34 PM CDTSpecial Marine WarningMOB116 min
May 20, 10:58 PM CDTSevere Thunderstorm WarningMOBCovington47 min
May 20, 11:14 PM CDTAreal Flood AdvisoryMOBCovington, Crenshaw3 hr
May 20, 11:40 PM CDTSpecial Marine WarningMOB2 hr
May 20, 11:59 PM CDTAreal Flood WarningMOBBaldwin, Clarke, Mobile, Washington12 hr
May 21, 12:18 AM CDTSpecial Marine WarningMOB57 min
May 21, 1:30 AM CDTAreal Flood WarningMOBMobile12 hr
May 21, 1:55 AM CDTSpecial Marine WarningMOB95 min
May 21, 3:21 PM CDTFlash Flood WatchMOBBaldwin, Butler, Choctaw, Clarke, Conecuh, Covington and 6 more47 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.