Alert archive / Florida / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 174, NWS Tallahassee, FL

August 13, 2008Bay County, Walton County, Washington County, Florida

NWS Tallahassee, FL issued this severe thunderstorm warning at Aug 13, 2008, 6:51 AM CDT for Bay County, Walton County, Washington County, Florida. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 13, 2008, 6:51 AM CDT (11:51 UTC)
Expired
Aug 13, 2008, 7:30 AM CDT
In force
39 min
Issued by
NWS Tallahassee, FL
Area
Storm-based polygon

Counties Bay County, FL, Walton County, FL, Washington County, FL

The radar

The Eglin Afb radar (KEVX), 13 km from the middle of the area, began a volume at 11:50 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 13, 3:02 AM CDTTornado WatchSPC7 hr

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 11.9 hours before the alert went out and 146 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 2008-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 512 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tallahassee Rgnl, FL at 00:00Z on 2008-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 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
512 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
755 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
-26 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tallahassee, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 13, 3:56 AM CDT, 2 hours 55 minutes earlier.

Area forecast discussion, Aug 13, 3:56 AM CDT, 2 hours 55 minutes before
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE TALLAHASSEE FL
455 AM EDT WED 13 208

***A TORNADO WATCH HAS BEEN ISSUED FOR OUR ENTIRE CWA UNTIL NOON
EDT. ALL ZONES INCLUDE SEVERE WEATHER WORDING FOR FIRST PERIOD.
CORRECTED WWA SECTION TO INCLUDE ALL MARINE ZONES IN THE SCA. ***

......................

.SYNOPSIS...THE SQUALL LINE WEAKENED AS IT MOVED INTO OUR CWA LATE
LAST NIGHT/EARLY THIS MORNING. A FEW LOCATIONS SAW BRIEF GUSTY WINDS
JUST OVER 30 KNOTS AND SEVERAL AREAS RECEIVED HEAVY DOWNPOURS.
HOWEVER...SO FAR NO FLOODING ISSUES AS THE CONVECTIVE LINE
PROGRESSED STEADILY TO THE EAST WITH NO APPRECIABLE ECHO TRAINING.
AS OF 07Z...THE NARROW BAND OF MODERATE TO HEAVY RAIN WAS ALONG A
VALDOSTA TO ST. MARKS LINE. SCATTERED CONVECTION EXTENDED WESTWARD
ACROSS THE REMAINDER OF OUR CWA.

&&

.SHORT TERM...(TODAY THROUGH FRIDAY)...THE STRONG SHORTWAVE AND
SURFACE LOW CURRENTLY MOVING INTO WEST CENTRAL ALABAMA WILL MOVE
EAST INTO COASTAL SOUTH CAROLINA EARLY THIS AFTERNOON AND THEN RACE
TO THE NORTHEAST ON THURSDAY. AS THE SURFACE LOW LIFTS OUT...IT WILL
DRAG THE COLD FRONT ACR
Hazardous weather outlook, Aug 13, 4:53 AM CDT, 1 hour 58 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TALLAHASSEE FL
553 AM EDT WED AUG 13 2008

ALZ065>069-FLZ007>019-026>029-034-GAZ120>131-142>148-155>161-
GMZ730-750-755-765-770-775-141000-
COFFEE-DALE-HENRY-GENEVA-HOUSTON-INLAND WALTON-COASTAL WALTON-
HOLMES-WASHINGTON-JACKSON-BAY-CALHOUN-GULF-FRANKLIN-GADSDEN-LEON-
JEFFERSON-MADISON-LIBERTY-WAKULLA-TAYLOR-LAFAYETTE-DIXIE-QUITMAN-
CLAY-RANDOLPH-TERRELL-DOUGHERTY-LEE-WORTH-TURNER-TIFT-BEN HILL-
IRWIN-EARLY-MILLER-BAKER-MITCHELL-COLQUITT-COOK-BERRIEN-SEMINOLE-
DECATUR-GRADY-THOMAS-BROOKS-LOWNDES-LANIER-
APALACHEE BAY OR COASTAL WATERS FROM KEATON BEACH TO OCHLOCKONEE
RIVER FL OUT TO 20 NM-
COASTAL WATERS FROM APALACHICOLA TO DESTIN FL OUT 20 NM-
COASTAL WATERS FROM  OCHLOCKONEE RIVER TO APALACHICOLA FL OUT TO
20 NM-
COASTAL WATERS FROM  SUWANNEE RIVER TO KEATON BEACH OUT 20 NM-
WATERS FROM APALACHICOLA TO DESTIN FL FROM 20 TO 60 NM-
WATERS FROM  SUWANNEE RIVER TO APALACHICOLA FL FROM 20 TO 60 NM-
553 AM EDT WED AUG 13 2008 /453 AM CDT WED AUG 13 2008/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST ALABAMA...
SOUTHWEST AND SOUTH CENTRAL GEORGIA...AND THE FLORIDA BIG BEND
AND PANHANDLE...AND ADJACENT COASTAL WATERS.

...TORNADO WATCH 824 IN EFFECT UNTIL 12 NOON EDT /11 AM CDT/ THIS
MORNING...
...LAKE WIND ADVISORY IN EFFECT FROM 8 AM EDT /7 AM CDT/ THIS
MORNING TO 8 PM EDT /7 PM CDT/ THIS EVENING...
...HIGH SURF ADVISORY IN EFFECT FROM 11 AM EDT /10 AM CDT/ THIS
MORNING TO 4 AM EDT /3 AM CDT/ THURSDAY...

.DAY ONE...TODAY AND TONIGHT...
NUMEROUS SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A STRONG LOW
PRESSURE SYSTEM WILL SWEEP FROM WEST TO EAST ACROSS THE AREA THIS
MORNING...BECOMING LESS NUMEROUS IN THE AFTERNOON. SOME OF THE
STORMS MAY BE SEVERE WITH DAMAGING WINDS AND EVEN AN ISOLATED
TORNADO IS POSSIBLE. THUS...A TORNADO WATCH HAS BEEN ISSUED AND IS
IN EFFECT FOR THE ENTIRE TRI-STATE REGION UNTIL 12 NOON EDT. WINDS
WILL BE BREEZY TODAY AND A LAKE WIND ADVISORY IS IN EFFECT THIS
AFTERNOON UNTIL EARLY EVENING. A SMALL CRAFT ADVISORY IS IN EFFECT
FOR THE ENTIRE MARINE AREA AS WELL AS A HIGH SURF ADVISORY ALONG
THE PANHANDLE COASTAL COUNTIES INCLUDING FRANKLIN COUNTY UNTIL
EARLY THURSDAY MORNING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...
A MORE TYPICAL SUMMERTIME PATTERN IS EXPECTED THURSDAY INTO EARLY
NEXT WEEK...WITH SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS. WINDS AND SEAS WILL ALSO DIMINISH ACROSS THE
MARINE AREA THURSDAY AND REMAIN LOW AT LEAST THROUGH THE WEEKEND.

.SPOTTER INFORMATION STATEMENT...
SPOTTERS SHOULD CONSIDER THEMSELVES ACTIVATED AT LEAST UNTIL 12
NOON EDT TODAY.

FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE
WEBSITE ON THE INTERNET AT WEATHER.GOV...THEN CLICK ON YOUR AREA
OF INTEREST ON THE NATIONAL MAP.

BARRY

In the hours before

Special weather statement, Aug 13, 6:14 AM CDT, 37 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
714 AM EDT WED AUG 13 2008

FLZ012>014-131145-
BAY-CALHOUN-GULF-
614 AM CDT WED AUG 13 2008

...A SIGNIFICANT WEATHER ALERT IS IN EFFECT FOR BAY...CALHOUN AND
GULF COUNTIES...

* UNTIL 645 AM CDT

AT 611 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 10 MILES NORTHEAST OF CALLAWAY...MOVING EAST AT
44 MPH.

WINDS 40 TO 50 MPH ARE EXPECTED WITH THIS STORM.

ALSO...THIS STORM IS CAPABLE OF PRODUCING TORRENTIAL DOWNPOURS WHICH
MAY CAUSE LOCALIZED FLOODING OF STREETS AND LOW LYING AREAS.

RELAY REPORTS OF SIGNIFICANT WEATHER 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.

12-WATSON
Special weather statement, Aug 13, 6:47 AM CDT, 4 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
747 AM EDT WED AUG 13 2008

FLZ008-010-012-131230-
BAY-COASTAL WALTON-WASHINGTON-
647 AM CDT WED AUG 13 2008

...SIGNIFICANT WEATHER ALERT IN EFFECT FOR BAY...WALTON AND
WASHINGTON COUNTIES...

* UNTIL 730 AM CDT

AT 648 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 11 MILES SOUTHWEST
OF DE FUNIAK SPRINGS TO 20 MILES SOUTH OF SANTA ROSA BEACH...MOVING
EAST AT 45 MPH.

THESE STORMS WILL BE NEAR...
  LOWER GRAND LAGOON BY 715 AM CDT.
  UPPER GRAND LAGOON BY 720 AM CDT.
  SPRINGFIELD BY 725 AM CDT.

WINDS 40 TO 50 MPH ARE EXPECTED WITH THESE STORMS.

ALSO...THESE STORMS ARE CAPABLE OF PRODUCING TORRENTIAL DOWNPOURS
WHICH MAY CAUSE LOCALIZED FLOODING OF STREETS AND LOW LYING AREAS.

RELAY REPORTS OF SIGNIFICANT WEATHER 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.

8-JAMSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 11:50 PM CDTSpecial Marine WarningTAE13 hr
Aug 13, 1:43 AM CDTHigh Surf AdvisoryTAEBay, Franklin, Gulf, Walton32 hr
Aug 13, 3:24 AM CDTAreal Flood AdvisoryTAEBay2 hr
Aug 13, 3:58 AM CDTLake Wind AdvisoryTAEBay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 10 more14 hr
Aug 13, 6:35 AM CDTSpecial Marine WarningTAE55 min
Aug 13, 7:33 AM CDTSevere Thunderstorm WarningTAEBay, Calhoun, Gulf, Liberty27 min
Aug 13, 9:12 AM CDTRiver Flood WarningTAEWakulla5 days
Aug 13, 10:02 AM CDTSpecial Marine WarningTAE58 min
Aug 13, 11:00 AM CDTSpecial Marine WarningTAE60 min
Aug 13, 11:47 AM CDTSpecial Marine WarningTAE58 min
Aug 13, 11:52 AM CDTSpecial Marine WarningTAE83 min
Aug 13, 12:59 PM CDTSpecial Marine WarningTAE91 min
Aug 13, 2:35 PM CDTSpecial Marine WarningTAE115 min
Aug 13, 8:38 AM CDTAreal Flood AdvisoryTAEClay52 min

Nearby

Severe Thunderstorm Warnings in Florida, 2008Every severe thunderstorm warning in 2008

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.