Alert archive / Florida / Flash Flood Warnings in 2017

Flash Flood Warning 30, NWS Mobile, AL

June 21, 2017Okaloosa County, Santa Rosa County, Florida

NWS Mobile, AL issued this flash flood warning at Jun 21, 2017, 6:56 AM CDT for Okaloosa County, Santa Rosa County, Florida. 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
Jun 21, 2017, 6:56 AM CDT (11:56 UTC)
Expired
Jun 21, 2017, 1:00 PM CDT
In force
6 hr
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Flood severity
None

Counties Okaloosa County, FL, Santa Rosa County, FL

The radar

The Eglin Afb radar (KEVX), 68 km from the middle of the area, began a volume at 11:57 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

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 11.9 hours before the alert went out and 225 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, Tallahassee Rgnl, FL at 00:00Z on 2017-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 439 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, Tallahassee Rgnl, FL at 00:00Z on 2017-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 173 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
439 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
713 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
173 m²/s²
0-3 km storm-relative helicity
249 m²/s²
Significant tornado parameter
0.3
Supercell composite
4.8

Open this sounding in Storm Lab

The text

As transmitted.

032 
WGUS54 KMOB 211156
FFWMOB
FLC091-113-211800-
/O.NEW.KMOB.FF.W.0030.170621T1156Z-170621T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
656 AM CDT WED JUN 21 2017

The National Weather Service in Mobile has issued a

* Flash Flood Warning for...
  Okaloosa County in northwestern Florida...
  Northeastern Santa Rosa County in northwestern Florida...

* Until 100 PM CDT Wednesday

* At 655 AM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have 
  already fallen. Flash flooding is expected to begin shortly if not 
  already ongoing.

* Some locations that will experience flooding include...
  Wright, Fort Walton Beach, Crestview, Niceville, Destin, Eglin AFB,
  Valparaiso, Mary Esther, Ocean City, Lake Lorraine, Baker,
  Shalimar, Jay, Cinco Bayou, Point Baker and Eglin Air Force Base.

Additional rainfall amounts of 2 to 3 inches are possible in the 
warned area over the next few hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3035 8681 3068 8680 3068 8719 3100 8718
      3100 8679 3083 8639 3046 8639 3046 8638
      3039 8638 3040 8639 3038 8640 3038 8650
      3036 8650

$$
1 follow-up statement
796 
WGUS74 KMOB 211551
FFSMOB

Flash Flood Statement
National Weather Service Mobile AL
1051 AM CDT WED JUN 21 2017

FLC091-113-211800-
/O.CON.KMOB.FF.W.0030.000000T0000Z-170621T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Okaloosa FL-Santa Rosa FL-
1051 AM CDT WED JUN 21 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 PM CDT FOR
OKALOOSA AND NORTHEASTERN SANTA ROSA COUNTIES...

At 1036 AM CDT, Doppler radar indicated bands of moderate to heavy 
rains continuing to lift northward off the Gulf over the warned 
area. 

Some locations that will experience flooding include...
Wright, Fort Walton Beach, Crestview, Niceville, Destin, Eglin AFB,
Valparaiso, Mary Esther, Ocean City, Lake Lorraine, Baker, Shalimar,
Jay, Cinco Bayou, Point Baker and Eglin Air Force Base.

Many area rain gauges over the warned area have reported upwards of 
4 to 6 inches of rain with a few localized areas seeing near 8 
inches. Most of these rains occurred overnight. Additional rainfall 
amounts of 2 to 4 inches are possible in the warned area over the 
warned area through the afternoon. Due to the very wet ground 
conditions, additional heavy rains will likely lead to runoff and 
exacerbate flooding problems.   

There have been reports of a few road closures due to flooding.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3035 8681 3068 8680 3068 8719 3100 8718
      3100 8679 3083 8639 3046 8639 3046 8638
      3039 8638 3040 8639 3038 8640 3038 8650
      3036 8650

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 1:56 AM CDTFlash Flood WarningMOBEscambia, Santa Rosa12 hr
Jun 21, 4:33 AM CDTTornado WarningMOBOkaloosa31 min
Jun 21, 6:11 AM CDTTornado WarningMOBOkaloosa22 min
Jun 21, 8:38 AM CDTRiver Flood WarningMOBEscambia48 hr
Jun 21, 8:38 AM CDTRiver Flood WarningMOBEscambia12 days
Jun 21, 8:38 AM CDTRiver Flood WarningMOBOkaloosa, Santa Rosa3 days
Jun 21, 8:38 AM CDTRiver Flood WarningMOBOkaloosa3 days
Jun 21, 12:05 PM CDTFlash Flood WarningMOBEscambia, Santa Rosa6 hr
Jun 21, 12:35 PM CDTAreal Flood WarningMOBEscambia, Okaloosa, Santa Rosa24 hr
Jun 21, 2:15 PM CDTTornado WarningMOBOkaloosa, Santa Rosa45 min
Jun 21, 2:44 PM CDTTornado WarningMOBOkaloosa, Santa Rosa30 min
Jun 21, 2:46 PM CDTTornado WarningMOBEscambia59 min
Jun 21, 3:53 PM CDTTornado WarningMOBEscambia52 min
Jun 21, 4:17 PM CDTTornado WarningMOBEscambia43 min
Jun 21, 5:51 PM CDTFlash Flood WarningMOBEscambia, Santa Rosa6 hr
Jun 21, 6:33 PM CDTSpecial Weather StatementMOBEscambia42 min

Nearby

Flash Flood Warnings in Florida, 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.