Alert archive / Alabama / Flash Flood Warnings in 2018

Flash Flood Warning 3, NWS Birmingham, AL

May 15, 2018Jefferson County, Alabama

NWS Birmingham, AL issued this flash flood warning at May 15, 2018, 6:15 PM CDT for Jefferson County, Alabama. It was in force for 3 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
May 15, 2018, 6:15 PM CDT (23:15 UTC)
Expired
May 15, 2018, 9:15 PM CDT
In force
3 hr
Issued by
NWS Birmingham, AL
Area
Storm-based polygon
Flood severity
None

County Jefferson County, AL

The radar

The Birmingham radar (KBMX), 36 km from the middle of the area, began a volume at 23:17 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 15, 6:25 PM CDTFLASH FLOOD1 E Dolomite, ALWATER COVERING PORTIONS OF INTERSTATE 20 NEAR ALLISON BONNETT MEMORIAL DRIVE EXIT.
May 15, 6:30 PM CDTFLASH FLOODMidfield, ALSTREET FLOODING ALONG WOODWARD RD AT BROOKWOOD RD E. TIME ESTIMATED.
May 15, 6:45 PM CDTFLASH FLOOD1 Wsw Midfield, ALROAD IMPASSABLE NEAR INTERSECTION OF WOODWARD RD AND DOCTOR M.L.K. JR DR.

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 12:00Z, 11.3 hours before the alert went out and 35 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 12:00Z on 2018-05-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 85 joules per kilogram.LCLLFCEL10008507005003002001001 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, Birmingham, AL at 12:00Z on 2018-05-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
85 J/kg
Mixed-layer CIN
-206 J/kg
Mixed-layer LCL
1464 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.3

Open this sounding in Storm Lab

The text

As transmitted.

485 
WGUS54 KBMX 152315
FFWBMX
ALC073-160215-
/O.NEW.KBMX.FF.W.0003.180515T2315Z-180516T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Birmingham AL
615 PM CDT TUE MAY 15 2018

The National Weather Service in Birmingham has issued a

* Flash Flood Warning for...
  South central Jefferson County in central Alabama...

* Until 915 PM CDT.

* At 614 PM CDT, local law enforcement reported thunderstorms
  producing heavy rain across the warned area. Flash flooding is
  expected.

* Some locations that will experience flooding include...
  Southwestern Birmingham, Bessemer, Hueytown, Fairfield, Pleasant
  Grove, Midfield, Brighton, Lipscomb, McDonald Chapel and Dolomite.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 3353 8692 3347 8684 3338 8689 3340 8698
      3350 8698

$$

61

The office that day

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

IssuedProductOfficeCountiesLasted
May 15, 1:47 PM CDTSpecial Weather StatementBMXChilton43 min
May 15, 5:19 PM CDTSpecial Weather StatementBMXJefferson26 min
May 15, 5:34 PM CDTSevere Thunderstorm WarningBMXJefferson26 min
May 15, 6:05 PM CDTSpecial Weather StatementBMXJefferson25 min
May 15, 6:58 PM CDTSpecial Weather StatementBMXBlount32 min

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.