Alert archive / Florida / Flash Flood Warnings in 2021

Flash Flood Warning 81, NWS Mobile, AL

September 16, 2021Okaloosa County, Santa Rosa County, Florida

NWS Mobile, AL issued this flash flood warning at Sep 16, 2021, 2:14 PM CDT for Okaloosa County, Santa Rosa County, Florida. It was in force for 6 hr. 2 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: Sep 16, 2021, 2:14 PM CDT (19:14 UTC)
Expired: Sep 16, 2021, 8:15 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), 87 km from the middle of the area, began a volume at 19:18 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
Sep 16, 2:40 PM CDT	FLASH FLOOD	Navarre, FL	ORTEGA ST AND ONICH DR IN NAVARRE IS CLOSED DUE TO WATER OVER THE ROAD. REPORT VIA SOCIAL MEDIA.
Sep 16, 4:30 PM CDT	FLASH FLOOD	Navarre, FL	WATER OVER THE ROAD ALONG AVENIDA DE SOL NORTH OF TORRES ST AND ALONG HIGH SCHOOL BLVD. REPORTS OF NUMEROUS FLOODED YARDS IN NAVARRE. PHOTOS, VIDEOS, AND REPORTS VIA SOCIAL MEDIA.

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

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 7.2 hours before the alert went out and 241 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: 618 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 655 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 159 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted.

242 
WGUS54 KMOB 161914
FFWMOB
FLC091-113-170115-
/O.NEW.KMOB.FF.W.0081.210916T1914Z-210917T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mobile AL
214 PM CDT Thu Sep 16 2021

The National Weather Service in Mobile has issued a

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

* Until 815 PM CDT Thursday.

* At 214 PM CDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 3 inches of rain have fallen. The expected rainfall rate is 
  2 to 3 inches in 1 hour. Additional rainfall amounts of 1 to 3 
  inches are possible in the warned area. Flash flooding is ongoing 
  or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Navarre Beach, Wynnehaven Beach, Harper and Holley.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3044 8691 3051 8691 3049 8668 3040 8669
      3039 8669 3036 8691

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...2-3 INCHES IN 1 HOUR

$$

MM

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 16, 5:18 AM CDT	Areal Flood Advisory	MOB	Okaloosa	117 min
Sep 16, 8:22 AM CDT	Areal Flood Advisory	MOB	Escambia, Santa Rosa	3 hr
Sep 16, 12:10 PM CDT	Special Weather Statement	MOB	Santa Rosa	50 min
Sep 16, 12:26 PM CDT	Areal Flood Advisory	MOB	Okaloosa, Santa Rosa	3 hr
Sep 16, 3:35 PM CDT	Areal Flood Advisory	MOB	Okaloosa	115 min
Sep 16, 4:04 PM CDT	Flash Flood Warning	MOB	Okaloosa	6 hr

Nearby

Flash Flood Warnings in Florida, 2021 Every flash flood warning in 2021

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.