Alert archive / Florida / Tornado Watches in 2016

Tornado Watch 515

December 5, 2016Baldwin County, Geneva County, Houston County, Alabama; 10 counties in Florida

The Storm Prediction Center issued this tornado watch at Dec 5, 2016, 1:10 PM CST for Baldwin County, Geneva County, Houston County, Alabama; 10 counties in Florida. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued: Dec 5, 2016, 1:10 PM CST (19:10 UTC)
Expired: Dec 5, 2016, 8:00 PM CST
In force: 7 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1 in
Strongest gust expected: 60 kt

Counties Baldwin County, AL, Geneva County, AL, Houston County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL

The radar

The Eglin Afb radar (KEVX), 99 km from the middle of the area, began a volume at 19:11 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: 30%
One or more gusts of 65 knots or more: 10%
Ten or more severe hail reports: 30%
One or more hailstones of 2 inches or more: 10%
Six or more combined severe hail and wind reports: 70%

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 12:00Z, 7.2 hours before the alert went out and 242 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: 20 J/kg
Mixed-layer CIN: -158 J/kg
Mixed-layer LCL: 731 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 198 m²/s²
0-3 km storm-relative helicity: 240 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

089 
WWUS20 KWNS 051908
SEL5  
SPC WW 051908
ALZ000-FLZ000-CWZ000-060200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 515
NWS STORM PREDICTION CENTER NORMAN OK
110 PM CST MON DEC 5 2016

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTHWEST ALABAMA
  FLORIDA PANHANDLE
  COASTAL WATERS

* EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 110 PM UNTIL
  800 PM CST.

* PRIMARY THREATS INCLUDE...
  A COUPLE TORNADOES POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
  ISOLATED LARGE HAIL EVENTS TO 1 INCHES IN DIAMETER POSSIBLE

SUMMARY...THUNDERSTORMS ALONG AND JUST OFF THE GULF COAST WILL MOVE
ASHORE DURING THE NEXT FEW HOURS...POSING A RISK OF LOCALLY DAMAGING
WIND GUSTS AND A TORNADO OR TWO.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 65 MILES SOUTHWEST OF PENSACOLA FL TO
40 MILES EAST SOUTHEAST OF PANAMA CITY FL. FOR A COMPLETE DEPICTION
OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS
WOU5).

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.

&&

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN
STORM MOTION VECTOR 23035.

...HART

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 5, 5:26 PM CST	Mesoscale Discussion	SPC	Baldwin, Geneva, Houston	2 hr
Dec 5, 12:29 PM CST	Mesoscale Discussion	SPC	Bay, Calhoun, Escambia, Gadsden, Gulf, Holmes and 6 more	2 hr

Nearby

Tornado Watches in Florida, 2016 Tornado Watches in Alabama, 2016 Every tornado watch in 2016

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.