Alert archive / Florida / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 31, NWS Mobile, AL

January 21, 2017Okaloosa County, Florida

NWS Mobile, AL issued this severe thunderstorm warning at Jan 21, 2017, 9:56 AM CST for Okaloosa County, Florida. It was in force for 34 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jan 21, 2017, 9:56 AM CST (15:56 UTC)
Expired
Jan 21, 2017, 10:30 AM CST
In force
34 min
Issued by
NWS Mobile, AL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Okaloosa County, FL

The radar

The Eglin Afb radar (KEVX), 61 km from the middle of the area, began a volume at 15:56 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
Jan 21, 3:56 AM CSTTornado WatchSPC8 hr

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 3.9 hours before the alert went out and 216 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 12:00Z on 2017-01-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 352 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 12:00Z on 2017-01-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 square meters per square second.1939587897117Sfc1 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
352 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
613 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.0

Open this sounding in Storm Lab

The text

As transmitted.

591 
WUUS54 KMOB 211556
SVRMOB
FLC091-211630-
/O.NEW.KMOB.SV.W.0031.170121T1556Z-170121T1630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mobile AL
956 AM CST SAT JAN 21 2017

The National Weather Service in Mobile has issued a

* Severe Thunderstorm Warning for...
  Okaloosa County in northwestern Florida...

* Until 1030 AM CST

* At 956 AM CST, severe thunderstorms were located along a line
  extending from Crestview to near Navarre Beach, moving east at 55
  mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to roofs, siding, and trees. 

* Locations impacted include...
  Wright, Fort Walton Beach, Crestview, Niceville, Destin, Eglin AFB,
  Valparaiso, Mary Esther, Ocean City, Lake Lorraine, Shalimar, Cinco
  Bayou and Eglin Air Force Base.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

A tornado watch remains in effect until 1100 AM CST for northwestern
Florida.

LAT...LON 3040 8630 3042 8631 3038 8633 3040 8639
      3038 8640 3038 8650 3035 8650 3037 8689
      3039 8680 3039 8684 3038 8688 3040 8688
      3041 8680 3060 8680 3079 8672 3082 8639
      3046 8639 3048 8628 3040 8628
TIME...MOT...LOC 1556Z 269DEG 47KT 3076 8661 3044 8680 

HAIL...<.75IN
WIND...60MPH
 
$$
1 follow-up statement
177 
WWUS54 KMOB 211625
SVSMOB

Severe Weather Statement
National Weather Service Mobile AL
1025 AM CST SAT JAN 21 2017

FLC091-211630-
/O.CON.KMOB.SV.W.0031.000000T0000Z-170121T1630Z/
Okaloosa FL-
1025 AM CST SAT JAN 21 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1030 AM CST
FOR SOUTHERN OKALOOSA COUNTY...

At 1024 AM CST, severe thunderstorms were located along a line
extending from 7 miles north of Eglin Air Force Base to Fort Walton
Beach, moving east at 30 mph.  A new severe thunderstorm warning may
soon be issued for this area.

HAZARD...60 mph wind gusts. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to roofs, siding, and trees. 

Locations impacted include...
Wright, Fort Walton Beach, Niceville, Destin, Eglin AFB, Valparaiso,
Mary Esther, Ocean City, Lake Lorraine, Shalimar, Cinco Bayou and
Eglin Air Force Base.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

A tornado watch remains in effect until 1100 AM CST for northwestern
Florida.

LAT...LON 3040 8630 3042 8631 3038 8633 3040 8639
      3038 8640 3038 8650 3035 8650 3037 8682
      3037 8683 3039 8680 3039 8681 3041 8680
      3049 8670 3059 8655 3068 8639 3046 8639
      3048 8628 3040 8628
TIME...MOT...LOC 1624Z 276DEG 25KT 3072 8627 3043 8664 

HAIL...<.75IN
WIND...60MPH
 
$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 20, 8:47 PM CSTRiver Flood WarningMOBEscambia25 hr
Jan 20, 8:48 PM CSTRiver Flood WarningMOBOkaloosa, Santa Rosa3 days
Jan 20, 8:49 PM CSTRiver Flood WarningMOBOkaloosa25 hr
Jan 20, 10:18 PM CSTRip Current StatementMOBEscambia, Okaloosa, Santa Rosa56 hr
Jan 21, 7:28 AM CSTWind AdvisoryMOBEscambia, Okaloosa, Santa Rosa4 hr
Jan 21, 9:14 AM CSTSpecial Weather StatementMOBEscambia, Okaloosa, Santa Rosa91 min
Jan 21, 9:25 AM CSTSevere Thunderstorm WarningMOBOkaloosa50 min
Jan 21, 10:28 AM CSTSevere Thunderstorm WarningMOBOkaloosa32 min

Nearby

Severe Thunderstorm Warnings in Florida, 2017Every severe thunderstorm 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.