Alert archive / Florida / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 41, NWS Mobile, AL

April 4, 2011Okaloosa County, Santa Rosa County, Florida; Covington County, Alabama

NWS Mobile, AL issued this severe thunderstorm warning at Apr 4, 2011, 10:46 PM CDT for Okaloosa County, Santa Rosa County, Florida; Covington County, Alabama. It was in force for 44 min. 5 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
Apr 4, 2011, 10:46 PM CDT (03:46 UTC)
Expired
Apr 4, 2011, 11:30 PM CDT
In force
44 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon

Counties Covington County, AL, 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 03:49 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

TimeReportWhereRemark
Apr 4, 11:00 PM CDTTSTM WND DMGBaker, FLMUCH OF BAKER HAD TREES AND POWER LINES DOWN. ONE AREA OF HEAVY DAMAGE WAS ON DAIRY ROAD JUST NORTHEAST OF BAKER, WITH SIGNIFICANT TREE DAMAGE, 2 HOUSES WITH STRUCTURAL DAMAGE, AND POWER LINES DOWN WITH POLES SNAPPED.
Apr 4, 11:08 PM CDTTSTM WND DMG2 Se Laurel Hill, FLTWO LARGE TREES BLOWN DOWN, ONE 3 FEET IN DIAMETER, WITH ROOFING SHINGLES DAMAGED TO SINGLE FAMILY RESIDENCE.
Apr 4, 11:08 PM CDTTSTM WND DMGFlorala, ALACCORDING TO EMA...MULTIPLE REPORTS OF TREES AND POWERLINES DOWN NEAR THE TOWN OF FLORALA. TIME ESTIMATED FROM RADAR.
Apr 4, 11:13 PM CDTTSTM WND DMG8 E Crestview, FLSKYWARN SPOTTER REPORTS PINE TREE DOWN ACROSS HWY 90...3 MILES WEST OF THE OKALOOSA AND WALTON COUNTY LINE. TIME ESTIMATED FROM RADAR.
Apr 4, 11:30 PM CDTTSTM WND DMGFlorala, ALNUMEROUS MEDIUM TO LARGE TREES AND POWER LINES DOWN. 1 HOME WITH STRUCTURAL DAMAGE. NORTHERN PART OF TOWN WITHOUT POWER UNTIL THIS MORNING 04/05/11.

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

The watch it was issued in

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

IssuedProductOfficeLasted
Apr 4, 5:28 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 3.8 hours before the alert went out and 224 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 2011-04-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1916 joules per kilogram.LCLEL10008507005003002001001 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 2011-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 189 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
1916 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
521 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
189 m²/s²
0-3 km storm-relative helicity
197 m²/s²
Significant tornado parameter
1.6
Supercell composite
9.6

Open this sounding in Storm Lab

The text

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

173 
WUUS54 KMOB 050346
SVRMOB
ALC039-FLC091-113-050430-
/O.NEW.KMOB.SV.W.0041.110405T0346Z-110405T0430Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOBILE AL
1046 PM CDT MON APR 4 2011

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  OKALOOSA COUNTY IN NORTHWEST FLORIDA...
  THIS INCLUDES THE CITIES OF...LAKE LORRAINE...WRIGHT...
  VALPARAISO...OCEAN CITY...NICEVILLE...MARY ESTHER...FORT WALTON
  BEACH...EGLIN AFB...DESTIN...CRESTVIEW...
  SOUTHEASTERN SANTA ROSA COUNTY IN NORTHWEST FLORIDA...
  SOUTHEASTERN COVINGTON COUNTY IN SOUTH CENTRAL ALABAMA...
  THIS INCLUDES THE CITIES OF...OPP...FLORALA...

* UNTIL 1130 PM CDT

* AT 1044 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM 6 MILES NORTHEAST OF OPP TO 15 MILES SOUTHWEST OF ANDALUSIA TO
  GULF BREEZE...AND MOVING EAST AT 55 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  ONYCHA AROUND 1055 PM CDT...
  LAUREL HILL AROUND 1100 PM CDT...
  CRESTVIEW AND LOCKHART AROUND 1105 PM CDT...
  FLORALA AROUND 1110 PM CDT...
  CINCO BAYOU...WRIGHT...OCEAN CITY AND MARY ESTHER AROUND 1115 PM
  CDT...
  SHALIMAR AROUND 1120 PM CDT...

THIS INCLUDES INTERSTATE 10 IN FLORIDA BETWEEN MILE MARKERS 29 AND
67.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT TUESDAY MORNING
FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA AND SOUTHEAST
MISSISSIPPI.

&&

LAT...LON 3098 8638 3046 8638 3046 8642 3049 8645
      3044 8658 3041 8652 3043 8646 3039 8638
      3038 8716 3042 8700 3046 8693 3051 8703
      3045 8706 3044 8709 3051 8709 3138 8622
      3134 8618 3100 8617
TIME...MOT...LOC 0346Z 271DEG 50KT 3135 8615 3113 8659
          3037 8715

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 4, 9:44 PM CDTSevere Thunderstorm WarningMOBEscambia, Okaloosa, Santa Rosa61 min
Apr 4, 11:01 PM CDTTornado WarningMOBOkaloosa14 min
Apr 4, 11:30 PM CDTSevere Thunderstorm WarningMOBOkaloosa15 min
Apr 4, 7:05 PM CDTSevere Thunderstorm WarningMOBChoctaw, Clarke, Washington55 min
Apr 4, 7:08 PM CDTTornado WarningMOBChoctaw, Clarke, Washington67 min
Apr 4, 7:30 PM CDTSevere Thunderstorm WarningMOBChoctaw, Clarke, Mobile, Washington, Wilcox60 min
Apr 4, 7:38 PM CDTTornado WarningMOBWashington56 min
Apr 4, 7:54 PM CDTTornado WarningMOBChoctaw, Clarke, Washington53 min
Apr 4, 8:21 PM CDTTornado WarningMOBClarke, Monroe, Washington39 min
Apr 4, 8:30 PM CDTSevere Thunderstorm WarningMOBBaldwin, Butler, Clarke, Conecuh, Escambia, Mobile and 3 more60 min
Apr 4, 9:41 PM CDTSevere Thunderstorm WarningMOBButler, Conecuh, Covington, Crenshaw, Escambia64 min
Apr 4, 9:47 PM CDTSpecial Marine WarningMOB88 min
Apr 4, 11:36 PM CDTSpecial Marine WarningMOB84 min
Apr 5, 5:09 AM CDTFire Weather WatchMOBButler, Conecuh, Covington, Crenshaw, Escambia, Monroe and 1 more25 hr

Nearby

Severe Thunderstorm Warnings in Florida, 2011Severe Thunderstorm Warnings in Alabama, 2011Every severe thunderstorm 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.