Alert archive / Alabama / Flash Flood Warnings in 2017

Flash Flood Warning 8, NWS Birmingham, AL

May 20, 20174 counties in Alabama

NWS Birmingham, AL issued this flash flood warning at May 20, 2017, 7:45 PM CDT for 4 counties in Alabama. It was in force for 3 hr. 1 report 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, 7:45 PM CDT (00:45 UTC)
Expired: May 20, 2017, 10:45 PM CDT
In force: 3 hr
Issued by: NWS Birmingham, AL
Area: Storm-based polygon
Flood severity: None

Counties Chilton County, AL, Jefferson County, AL, Shelby County, AL, Talladega County, AL

The radar

The Birmingham radar (KBMX), 28 km from the middle of the area, began a volume at 00:46 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

Time	Report	Where	Remark
May 20, 9:00 PM CDT	FLASH FLOOD	1 Ene Kingston, AL	SEVERAL ROADWAYS ARE FLOODED AND IMPASSABLE. VILLAGE CREEK AT AVENUE W AND 5 MILE CREEK AT KETONA WERE OVER FLOOD STAGE AND PRODUCED FLASH FLOODING.

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

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 0.8 hours before the alert went out and 201 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: 86 J/kg
Mixed-layer CIN: -265 J/kg
Mixed-layer LCL: 1583 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 101 m²/s²
0-3 km storm-relative helicity: 91 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

036 
WGUS54 KBMX 210045
FFWBMX
ALC021-073-117-121-210345-
/O.NEW.KBMX.FF.W.0008.170521T0045Z-170521T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Birmingham has issued a

* Flash Flood Warning for...
  Southwestern Talladega County in east central Alabama...
  North central Chilton County in Alabama...
  Shelby County in Alabama...
  Eastern Jefferson County in Alabama...

* Until 1045 PM CDT

* At 743 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to two inches of rain have 
  already fallen and another inch of so of rain is possible. Flash 
  flooding is expected to begin shortly. Five Mile Creek at Ketona 
  will go over flood stage and Village Creek at Avenue W will be 
  between 6 and 10 feet. Other creeks and streams will also be out 
  of there banks and become dangerous.

* Some locations that will experience flooding include...
  Birmingham, Hoover, Vestavia Hills, Alabaster, Bessemer, Homewood,
  Pelham, Mountain Brook, Trussville, Helena, Hueytown, Gardendale,
  Irondale, Leeds, Moody, Calera, Fairfield, Chelsea, Fultondale and
  Montevallo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Keep children away from storm drains, culverts, creeks and streams.
Water levels can rise rapidly and sweep children away.

&&

LAT...LON 3377 8665 3376 8657 3370 8652 3362 8655
      3356 8655 3355 8648 3350 8648 3350 8639
      3334 8636 3310 8648 3309 8651 3305 8652
      3304 8688 3310 8697 3316 8697 3317 8701
      3325 8703 3326 8706 3384 8676

$$

75

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 7:11 PM CDT	Special Weather Statement	BMX	Elmore	34 min
May 20, 7:18 PM CDT	Flash Flood Warning	BMX	Cherokee	3 hr
May 20, 7:31 PM CDT	Special Weather Statement	BMX	Coosa, Tallapoosa	29 min
May 20, 7:51 PM CDT	Flash Flood Warning	BMX	Autauga, Dallas, Elmore, Lowndes, Montgomery	3 hr
May 20, 8:24 PM CDT	Areal Flood Advisory	BMX	Calhoun, Etowah, St. Clair, Talladega	3 hr
May 20, 8:26 PM CDT	Special Weather Statement	BMX	Cleburne	64 min
May 20, 8:29 PM CDT	River Flood Warning	BMX	Jefferson	14 hr
May 20, 9:00 PM CDT	Flash Flood Warning	BMX	Elmore, Montgomery	3 hr
May 20, 9:21 PM CDT	Special Weather Statement	BMX	Lowndes	24 min
May 20, 9:45 PM CDT	Special Weather Statement	BMX	Pike	60 min
May 20, 10:17 PM CDT	Special Weather Statement	BMX	Bullock	58 min
May 20, 10:23 PM CDT	Flash Flood Warning	BMX	Cherokee	3 hr
May 20, 10:35 PM CDT	Flash Flood Warning	BMX	Autauga, Dallas, Elmore, Lowndes, Montgomery	6 hr
May 20, 11:04 PM CDT	Special Weather Statement	BMX	Macon	41 min
May 20, 11:13 PM CDT	Special Weather Statement	BMX	Lee	32 min
May 20, 11:40 PM CDT	Areal Flood Advisory	BMX	Macon, Tallapoosa	3 hr
May 20, 11:44 PM CDT	Special Weather Statement	BMX	Lee, Russell	61 min
May 21, 12:01 AM CDT	Flash Flood Warning	BMX	Macon	3 hr
May 21, 12:03 AM CDT	Special Weather Statement	BMX	Barbour	42 min
May 21, 12:30 AM CDT	Areal Flood Advisory	BMX	Lee	3 hr
May 21, 12:33 AM CDT	Special Weather Statement	BMX	Chambers, Lee	57 min
May 21, 1:14 AM CDT	Special Weather Statement	BMX	Chambers	46 min
May 21, 1:40 AM CDT	Areal Flood Advisory	BMX	Randolph	3 hr
May 21, 4:25 AM CDT	Areal Flood Warning	BMX	Lowndes, Montgomery	3 hr
May 21, 6:55 AM CDT	River Flood Warning	BMX	Montgomery	48 hr
May 21, 4:05 PM CDT	Flash Flood Watch	BMX	Autauga, Barbour, Bibb, Bullock, Chambers, Chilton and 17 more	47 hr
May 21, 6:17 PM CDT	Special Weather Statement	BMX	Lamar, Marion	43 min

Nearby

Flash Flood Warnings in Alabama, 2017 Every 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.