Alert archive / Florida / Tornado Watches in 2018

Tornado Watch 50

April 14, 20185 counties in Alabama; 7 counties in Florida; 6 counties in Georgia

The Storm Prediction Center issued this tornado watch at Apr 14, 2018, 10:58 PM CDT for 5 counties in Alabama; 7 counties in Florida; 6 counties in Georgia. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Apr 14, 2018, 10:58 PM CDT (03:58 UTC)
Expired
Apr 15, 2018, 7:00 AM CDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt

Counties Coffee County, AL, Dale County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Bay County, FL, Calhoun County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Walton County, FL, Washington County, FL, Clay County, GA, Early County, GA, Miller County, GA, Quitman County, GA, Randolph County, GA, Seminole County, GA

The radar

The Ft Rucker radar (KEOX), 58 km from the middle of the area, began a volume at 04:00 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
50%

Warnings issued inside it

3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 15, 2:28 AM CDTSevere Thunderstorm WarningTAEBay, Holmes, Walton, Washington48 min
Apr 15, 2:34 AM CDTSevere Thunderstorm WarningTAEDale, Geneva, Henry, Houston41 min
Apr 15, 6:09 AM CDTTornado WarningTAEBay, Calhoun, Gulf36 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 4.0 hours before the alert went out and 121 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 2018-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2018-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1537 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
79 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

133 
WWUS20 KWNS 150355
SEL0  
SPC WW 150355
ALZ000-FLZ000-GAZ000-CWZ000-151200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 50
NWS Storm Prediction Center Norman OK
1055 PM CDT Sat Apr 14 2018

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southeast Alabama
  Florida Panhandle
  Southwest Georgia
  Coastal Waters

* Effective this Saturday night and Sunday morning from 1055 PM
  until 700 AM CDT.

* Primary threats include...
  A couple tornadoes possible
  Scattered damaging wind gusts to 70 mph possible

SUMMARY...A squall line across the western Florida Panhandle and
south-central Alabama at late evening will continue
east-northeastward with some additional forward acceleration likely
overnight. A relatively moist environment and strong low-level shear
will support the possibility of a couple of tornadoes and localized
pockets of wind damage.

The tornado watch area is approximately along and 40 statute miles
east and west of a line from 30 miles north of Dothan AL to 40 miles
west of Apalachicola FL. For a complete depiction of the watch see
the associated watch outline update (WOUS64 KWNS WOU0).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 49...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 1 inch. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 24035.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 14, 9:27 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 10 more93 min
Apr 15, 1:45 AM CDTMesoscale DiscussionSPCCoffee, Dale, Geneva, Henry, Houston2 hr
Apr 15, 5:42 AM CDTMesoscale DiscussionSPCBay, Calhoun, Gulf, Jackson93 min
Apr 15, 8:34 AM CDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Columbia, Gilchrist, Hamilton and 4 more86 min
Apr 15, 9:12 AM CDTTornado WatchSPCAlachua, Baker, Bradford, Citrus, Clay, Columbia and 22 more8 hr
Apr 15, 11:18 AM CDTMesoscale DiscussionSPCHardee, Hillsborough, Manatee, Polk57 min
Apr 15, 1:30 PM CDTMesoscale DiscussionSPCClay, Duval, Lake, Manatee, Polk, Putnam and 1 more90 min
Apr 15, 3:42 PM CDTMesoscale DiscussionSPCBroward, Collier, DeSoto, Glades, Hardee, Hendry and 4 more63 min
Apr 15, 11:13 AM CDTTornado WatchSPCBurke, Columbia, Lincoln, McDuffie, Richmond9 hr

Nearby

Tornado Watches in Florida, 2018Tornado Watches in Georgia, 2018Tornado Watches in Alabama, 2018Every tornado watch in 2018

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.