Alert archive / Florida / Flash Flood Warnings in 2011

Flash Flood Warning 1, NWS Tallahassee, FL

July 17, 2011Franklin County, Gulf County, Florida

NWS Tallahassee, FL issued this flash flood warning at Jul 17, 2011, 9:24 AM EDT for Franklin County, Gulf County, Florida. 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: Jul 17, 2011, 9:24 AM EDT (13:24 UTC)
Expired: Jul 17, 2011, 12:15 PM EDT
In force: 3 hr
Issued by: NWS Tallahassee, FL
Area: Storm-based polygon
Flood severity: None

Counties Franklin County, FL, Gulf County, FL

The radar

The Tallahassee radar (KTLH), 95 km from the middle of the area, began a volume at 13:27 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
Jul 17, 12:00 PM EDT	HEAVY RAIN 5.72	Apalachicola Airport, FL	RAIN TOTAL FOR THE DAY THROUGH 12 PM EDT. 5.50 INCHES OF THAT FELL IN A 3 HOUR TIME PERIOD BETWEEN 7 AM AND 10 AM EDT. MINOR STREET FLOODING WAS REPORTED IN APALACHICOLA.

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, 1.4 hours before the alert went out and 97 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: 616 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 721 m above ground
0-6 km bulk shear: 1 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: 87 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

930 
WGUS52 KTAE 171324
FFWTAE
FLC037-045-171615-
/O.NEW.KTAE.FF.W.0001.110717T1324Z-110717T1615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TALLAHASSEE FL
924 AM EDT SUN JUL 17 2011

THE NATIONAL WEATHER SERVICE IN TALLAHASSEE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WESTERN FRANKLIN COUNTY IN FLORIDA...
  EASTERN GULF COUNTY IN THE PANHANDLE OF FLORIDA...

* UNTIL 1215 PM EDT/1115 AM CDT/

* AT 918 AM EDT...THE NATIONAL WEATHER SERVICE DETECTED VERY
  HEAVY RAIN FROM A SMALL GROUP OF SHOWERS AND THUNDERSTORMS 
  OVER AND AROUND APALACHICOLA...MOVING EAST AT 5 MPH. THESE 
  STORMS HAVE A HISTORY OF PRODUCING EXTREMELY HEAVY RAINFALL...WITH
  RADAR AND GAGE ESTIMATES OF 2 TO 4 INCHER PER HOUR. STORM
  TOTAL RAINFALL COULD EXCEED 8 INCHES IN SOME AREAS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DON'T DROWN.

* REPORT FLOODING OR FLOOD DAMAGE TO THE NATIONAL WEATHER SERVICE IN
TALLAHASSEE AT (8 5 0) 9 4 2 8 8 3 3. OR...YOU MAY CONTACT THE
NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT.
THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 2968 8518 2970 8514 2970 8516 2970 8518
      3001 8516 3001 8507 2997 8502 3001 8501
      3001 8476 2977 8477 2972 8488 2973 8492
      2978 8489 2978 8491 2971 8499 2971 8510
      2970 8513 2969 8511

$$

9-FOURNIER

The office that day

Everything else NWS Tallahassee, FL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 17, 8:13 AM EDT	Areal Flood Warning	TAE	Franklin, Gulf	3 hr

Nearby

Flash Flood Warnings in Florida, 2011 Every flash flood warning in 2011

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.