Alert archive / Alabama / Tornado Watches in 2015

Tornado Watch 552

November 18, 201528 counties in Alabama; 10 counties in Florida

The Storm Prediction Center issued this tornado watch at Nov 18, 2015, 8:25 AM CST for 28 counties in Alabama; 10 counties in Florida. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Nov 18, 2015, 8:25 AM CST (14:25 UTC)
Expired
Nov 18, 2015, 4:00 PM CST
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
60 kt
All 38 counties

Autauga County, AL, Baldwin County, AL, Barbour County, AL, Bullock County, AL, Butler County, AL, Clarke County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Dallas County, AL, Elmore County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pike County, AL, Russell County, AL, Washington County, AL, Wilcox 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), 95 km from the middle of the area, began a volume at 14:28 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
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Nov 18, 9:09 AM CSTSevere Thunderstorm WarningMOBOkaloosa51 min
Nov 18, 10:45 AM CSTTornado WarningMOBOkaloosa30 min
Nov 18, 10:45 AM CSTTornado WarningTAEWalton45 min
Nov 18, 10:57 AM CSTSevere Thunderstorm WarningMOBBaldwin48 min
Nov 18, 11:21 AM CSTTornado WarningTAEWalton39 min
Nov 18, 11:26 AM CSTTornado WarningTAECoffee49 min
Nov 18, 11:41 AM CSTTornado WarningMOBOkaloosa30 min
Nov 18, 12:00 PM CSTTornado WarningTAEWalton45 min
Nov 18, 12:49 PM CSTTornado WarningTAEGeneva26 min
Nov 18, 1:01 PM CSTTornado WarningTAECoffee44 min
Nov 18, 1:15 PM CSTTornado WarningTAEWalton45 min
Nov 18, 2:01 PM CSTSevere Thunderstorm WarningTAEDale44 min
Nov 18, 2:08 PM CSTSevere Thunderstorm WarningTAEHolmes, Walton, Washington52 min
Nov 18, 3:09 PM CSTTornado WarningTAEFranklin, Gulf51 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

Birmingham, AL (KBMX), launched 12:00Z, 2.4 hours before the alert went out and 215 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, Birmingham, AL at 12:00Z on 2015-11-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 19 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, Birmingham, AL at 12:00Z on 2015-11-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 475 square meters per square second.1939587897Sfc1 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
19 J/kg
Mixed-layer CIN
-274 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
475 m²/s²
0-3 km storm-relative helicity
594 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

591 
WWUS20 KWNS 181422
SEL2  
SPC WW 181422
ALZ000-FLZ000-CWZ000-182200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 552
NWS STORM PREDICTION CENTER NORMAN OK
825 AM CST WED NOV 18 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTHERN AND CENTRAL ALABAMA
  WESTERN FLORIDA PANHANDLE
  COASTAL WATERS

* EFFECTIVE THIS WEDNESDAY MORNING AND AFTERNOON FROM 825 AM
  UNTIL 400 PM CST.

* PRIMARY THREATS INCLUDE...
  A COUPLE TORNADOES POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

SUMMARY...THUNDERSTORMS ARE EXPECTED TO GRADUALLY INTENSIFY TODAY
WHILE SPREADING EAST ACROSS THE WATCH AREA.  THE STRONGEST STORMS
WILL BE CAPABLE OF A COUPLE TORNADOES AND DAMAGING OUTFLOW WINDS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 35 MILES SOUTH SOUTHEAST OF
CRESTVIEW FLORIDA TO 30 MILES NORTH NORTHEAST OF MONTGOMERY
ALABAMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).

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 551...

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 21035.


...MEAD

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 18, 1:14 AM CSTMesoscale DiscussionSPCChoctaw, Clarke, Fayette, Greene, Hale, Lamar and 8 more2 hr
Nov 18, 2:49 AM CSTTornado WatchSPCBaldwin, Choctaw, Clarke, Greene, Hale, Marengo and 4 more6 hr
Nov 18, 5:21 AM CSTMesoscale DiscussionSPCBaldwin, Choctaw, Clarke, Dallas, Fayette, Greene and 9 more114 min
Nov 18, 7:22 AM CSTMesoscale DiscussionSPCAutauga, Baldwin, Bibb, Butler, Chilton, Clarke and 14 more83 min
Nov 18, 10:51 AM CSTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bullock, Butler, Coffee and 17 more114 min
Nov 18, 1:39 PM CSTMesoscale DiscussionSPCBarbour, Coffee, Covington, Crenshaw, Dale, Geneva and 3 more2 hr
Nov 18, 2:16 PM CSTTornado WatchSPCCoffee, Dale, Geneva, Henry, Houston6 hr
Nov 18, 5:35 PM CSTMesoscale DiscussionSPCFranklin, Gadsden, Gulf, Jefferson, Leon, Liberty and 1 more115 min

Nearby

Tornado Watches in Alabama, 2015Tornado Watches in Florida, 2015Every tornado watch in 2015

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.