Alert archive / Alabama / Tornado Watches in 2015

Tornado Watch 2

January 3, 201521 counties in Alabama

The Storm Prediction Center issued this tornado watch at Jan 3, 2015, 3:18 PM CST for 21 counties in Alabama. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jan 3, 2015, 3:18 PM CST (21:18 UTC)
Expired: Jan 3, 2015, 8:00 PM CST
In force: 5 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1 in
Strongest gust expected: 60 kt

All 21 counties

Autauga County, AL, Bibb County, AL, Blount County, AL, Chilton County, AL, Dallas County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jefferson County, AL, Lamar County, AL, Lowndes County, AL, Marengo County, AL, Marion County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, St. Clair County, AL, Sumter County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL

The radar

The Columbus AFB radar (KGWX), 55 km from the middle of the area, began a volume at 21:22 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: 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

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

Issued	Product	Office	Counties	Lasted
Jan 3, 3:56 PM CST	Severe Thunderstorm Warning	BMX	Pickens	32 min
Jan 3, 4:02 PM CST	Tornado Warning	BMX	Sumter	11 min
Jan 3, 4:27 PM CST	Tornado Warning	BMX	Sumter	48 min
Jan 3, 4:34 PM CST	Tornado Warning	BMX	Greene, Pickens, Sumter	41 min
Jan 3, 4:44 PM CST	Tornado Warning	BMX	Lamar	46 min
Jan 3, 5:13 PM CST	Tornado Warning	BMX	Marion	47 min
Jan 3, 5:16 PM CST	Tornado Warning	BMX	Greene, Tuscaloosa	14 min
Jan 3, 5:39 PM CST	Severe Thunderstorm Warning	BMX	Winston	20 min
Jan 3, 6:02 PM CST	Severe Thunderstorm Warning	BMX	Greene, Hale	43 min
Jan 3, 6:11 PM CST	Flash Flood Warning	BMX	Greene, Pickens, Sumter	3 hr

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, 9.3 hours before the alert went out and 115 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 471 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 266 m²/s²
0-3 km storm-relative helicity: 377 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.

268 
WWUS20 KWNS 032118
SEL2  
SPC WW 032118
ALZ000-040200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 2
NWS STORM PREDICTION CENTER NORMAN OK
320 PM CST SAT JAN 3 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  WEST CENTRAL ALABAMA

* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 320 PM UNTIL
  800 PM CST.

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

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 40 STATUTE
MILES EAST AND WEST OF A LINE FROM 65 MILES NORTHEAST OF COLUMBUS
MISSISSIPPI TO 65 MILES SOUTH SOUTHWEST OF TUSCALOOSA 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 1...

DISCUSSION...SEVERE THUNDERSTORMS OVER CENTRAL MS WILL TRACK
NORTHEASTWARD THIS AFTERNOON AND EVENING INTO WESTERN AL...WITH A
CONTINUED RISK OF DAMAGING WINDS AND A FEW TORNADOES.

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.


...HART

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 3, 12:00 PM CST	Mesoscale Discussion	SPC	Baldwin, Mobile	90 min
Jan 3, 1:43 PM CST	Mesoscale Discussion	SPC	Choctaw, Sumter, Washington	92 min
Jan 3, 2:54 PM CST	Mesoscale Discussion	SPC	Bibb, Choctaw, Clarke, Dallas, Fayette, Greene and 11 more	96 min
Jan 3, 4:47 PM CST	Mesoscale Discussion	SPC	Autauga, Butler, Chilton, Conecuh, Coosa, Crenshaw and 6 more	58 min
Jan 3, 5:31 PM CST	Mesoscale Discussion	SPC	Choctaw	44 min
Jan 3, 5:59 PM CST	Mesoscale Discussion	SPC	Bibb, Colbert, Cullman, Fayette, Franklin, Greene and 11 more	61 min
Jan 3, 10:24 AM CST	Mesoscale Discussion	SPC	Amite, Clarke, Copiah, Covington, Forrest, Franklin and 26 more	2 hr
Jan 3, 11:04 AM CST	Tornado Watch	SPC	Adams, Amite, Choctaw, Claiborne, Clarke, Clay and 35 more	7 hr

Nearby

Tornado Watches in Alabama, 2015 Every 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.