Alert archive / Florida / Flash Flood Warnings in 2020

Flash Flood Warning 8, NWS Mobile, AL

April 23, 2020Escambia County, Santa Rosa County, Florida

NWS Mobile, AL issued this flash flood warning at Apr 23, 2020, 10:05 AM CDT for Escambia County, Santa Rosa County, Florida. It was in force for 2 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 23, 2020, 10:05 AM CDT (15:05 UTC)
Expired
Apr 23, 2020, 12:33 PM CDT
In force
2 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

Counties Escambia County, FL, Santa Rosa County, FL

The radar

The Mobile radar (KMOB), 87 km from the middle of the area, began a volume at 15:07 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 12:00Z, 3.1 hours before the alert went out and 235 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 12:00Z on 2020-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2572 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 12:00Z on 2020-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 424 square meters per square second.1939587897Sfc1 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
2572 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
498 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
424 m²/s²
0-3 km storm-relative helicity
449 m²/s²
Significant tornado parameter
7.7
Supercell composite
25.5

Open this sounding in Storm Lab

The text

As transmitted.

749 
WGUS54 KMOB 231505
FFWMOB
FLC033-113-232100-
/O.NEW.KMOB.FF.W.0008.200423T1505Z-200423T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
1005 AM CDT Thu Apr 23 2020

The National Weather Service in Mobile has issued a

* Flash Flood Warning for...
  Northern Santa Rosa County in northwestern Florida...
  Northwestern Escambia County in northwestern Florida...

* Until 400 PM CDT.

* At 1003 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across far northern Escambia and Santa Rosa Counties.
  Two to four inches of rain has already occurred near the Escambia 
  County Alabama border and an additional one to three inches is 
  likely as additional storms continue to move across the area. 
  Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Some locations that will experience flooding include...
  Century, Flomaton, Jay and Bratt. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3080 8758 3087 8764 3095 8759 3100 8760
      3100 8679 3085 8679

FLASH FLOOD...RADAR INDICATED

$$
1 follow-up statement
403 
WGUS74 KMOB 231733
FFSMOB

Flash Flood Statement
National Weather Service Mobile AL
1233 PM CDT Thu Apr 23 2020

FLC033-113-231742-
/O.CAN.KMOB.FF.W.0008.000000T0000Z-200423T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Santa Rosa FL-Escambia FL-
1233 PM CDT Thu Apr 23 2020

...THE FLASH FLOOD WARNING FOR NORTHERN SANTA ROSA AND NORTHWESTERN
ESCAMBIA COUNTIES IS CANCELLED...

Flash flooding is no longer expected to pose a threat, although 
areal flooding is still ongoing. An areal flood warning is now in 
effect.

LAT...LON 3080 8758 3087 8764 3095 8759 3100 8760
      3100 8679 3085 8679

$$

JLH

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 23, 6:50 AM CDTSevere Thunderstorm WarningMOBEscambia40 min
Apr 23, 7:35 AM CDTSevere Thunderstorm WarningMOBEscambia, Santa Rosa55 min
Apr 23, 8:12 AM CDTSevere Thunderstorm WarningMOBOkaloosa, Santa Rosa63 min
Apr 23, 10:27 AM CDTSevere Thunderstorm WarningMOBOkaloosa, Santa Rosa43 min
Apr 23, 10:28 AM CDTFlash Flood WarningMOBOkaloosa3 hr
Apr 23, 11:57 AM CDTSevere Thunderstorm WarningMOBEscambia, Santa Rosa48 min
Apr 23, 12:20 PM CDTSevere Thunderstorm WarningMOBOkaloosa40 min
Apr 23, 12:32 PM CDTAreal Flood WarningMOBEscambia, Santa Rosa6 hr
Apr 23, 1:29 PM CDTSevere Thunderstorm WarningMOBEscambia46 min
Apr 23, 2:13 PM CDTSevere Thunderstorm WarningMOBSanta Rosa47 min
Apr 23, 2:28 PM CDTSevere Thunderstorm WarningMOBOkaloosa, Santa Rosa47 min
Apr 23, 2:55 PM CDTTornado WarningMOBOkaloosa25 min

Nearby

Flash Flood Warnings in Florida, 2020Every flash flood warning in 2020

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.