Alert archive / Alabama / Tornado Watches in 2017

Tornado Watch 116

April 3, 201712 counties in Alabama; 10 counties in Florida

The Storm Prediction Center issued this tornado watch at Apr 3, 2017, 7:06 AM CDT for 12 counties in Alabama; 10 counties in Florida. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 3, 2017, 7:06 AM CDT (12:06 UTC)
Expired
Apr 3, 2017, 1:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 22 counties

Butler County, AL, Coffee County, AL, Conecuh County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Monroe 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), 82 km from the middle of the area, began a volume at 12:10 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
30%
One or more EF2 to EF5 tornadoes
5%
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

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

IssuedProductOfficeCountiesLasted
Apr 3, 7:26 AM CDTSevere Thunderstorm WarningMOBBaldwin, Butler, Clarke, Conecuh, Escambia, Mobile and 2 more49 min
Apr 3, 8:09 AM CDTSevere Thunderstorm WarningMOBBaldwin, Conecuh, Covington, Escambia, Mobile51 min
Apr 3, 8:26 AM CDTSevere Thunderstorm WarningMOBButler, Conecuh, Covington, Crenshaw, Escambia64 min
Apr 3, 8:54 AM CDTTornado WarningMOBCrenshaw13 min
Apr 3, 9:00 AM CDTSevere Thunderstorm WarningMOBBaldwin, Escambia, Mobile60 min
Apr 3, 9:01 AM CDTSevere Thunderstorm WarningTAECoffee, Dale, Geneva, Houston59 min
Apr 3, 9:36 AM CDTSevere Thunderstorm WarningMOBConecuh, Covington39 min
Apr 3, 9:43 AM CDTSevere Thunderstorm WarningMOBEscambia, Santa Rosa62 min
Apr 3, 9:48 AM CDTTornado WarningTAEDale27 min
Apr 3, 9:54 AM CDTSevere Thunderstorm WarningTAEDale, Henry66 min
Apr 3, 9:59 AM CDTSevere Thunderstorm WarningTAECoffee, Dale, Geneva, Houston61 min
Apr 3, 9:59 AM CDTTornado WarningMOBOkaloosa31 min
Apr 3, 10:14 AM CDTSevere Thunderstorm WarningMOBOkaloosa, Santa Rosa46 min
Apr 3, 10:46 AM CDTSevere Thunderstorm WarningMOBEscambia, Santa Rosa45 min
Apr 3, 10:51 AM CDTSevere Thunderstorm WarningTAEDale, Geneva, Houston39 min
Apr 3, 11:00 AM CDTSevere Thunderstorm WarningMOBOkaloosa, Santa Rosa31 min
Apr 3, 11:03 AM CDTSevere Thunderstorm WarningTAEBay, Holmes, Walton, Washington42 min
Apr 3, 11:28 AM CDTSevere Thunderstorm WarningTAEHenry, Houston47 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 12:00Z, 0.1 hours before the alert went out and 231 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 2017-04-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1400 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, Tallahassee Rgnl, FL at 12:00Z on 2017-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 136 square meters per square second.193958Sfc1 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
1400 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
580 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
136 m²/s²
0-3 km storm-relative helicity
248 m²/s²
Significant tornado parameter
1.5
Supercell composite
9.3

Open this sounding in Storm Lab

The text

As transmitted.

497 
WWUS20 KWNS 031203
SEL6  
SPC WW 031203
ALZ000-FLZ000-CWZ000-031800-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 116
NWS Storm Prediction Center Norman OK
705 AM CDT Mon Apr 3 2017

The NWS Storm Prediction Center has issued a

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

* Effective this Monday morning and afternoon from 705 AM until
  100 PM CDT.

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

SUMMARY...A squall line over southwest Alabama will continue moving
to the east through midday.  Bowing segments in the line will be
capable of producing occasional damaging gusts, while a tornado or
two will be possible with circulations embedded within the line.

The tornado watch area is approximately along and 75 statute miles
east and west of a line from 50 miles northwest of Dothan AL to 55
miles south southeast of Pensacola FL. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
WOU6).

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 114...WW 115...

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 550. Mean
storm motion vector 28025.

...Thompson

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 3, 1:48 AM CDTTornado WatchSPCBaldwin, Choctaw, Clarke, Mobile, Washington10 hr
Apr 3, 1:51 AM CDTMesoscale DiscussionSPCBibb, Blount, Calhoun, Cherokee, Clay, Cleburne and 6 more114 min
Apr 3, 3:59 AM CDTMesoscale DiscussionSPCAutauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 17 more2 hr
Apr 3, 4:25 AM CDTSevere Thunderstorm WatchSPCAutauga, Barbour, Bibb, Bullock, Chambers, Chilton and 14 more7 hr
Apr 3, 6:43 AM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Coffee, Conecuh, Covington and 9 more2 hr
Apr 3, 7:45 AM CDTMesoscale DiscussionSPCBarbour, Bullock, Chambers, Coosa, Elmore, Lee and 6 more90 min
Apr 3, 9:25 AM CDTMesoscale DiscussionSPCBarbour, Dale, Geneva, Henry, Houston, Lee and 1 more65 min
Apr 3, 12:32 PM CDTTornado WatchSPCCalhoun, Dixie, Franklin, Gadsden, Gulf, Jefferson and 6 more6 hr
Apr 3, 2:21 PM CDTMesoscale DiscussionSPCBay, Calhoun, Franklin, Gadsden, Gulf, Jefferson and 5 more54 min
Apr 3, 5:57 PM CDTMesoscale DiscussionSPCBaker, Bradford, Clay, Columbia, Dixie, Duval and 17 more93 min
Apr 3, 9:07 AM CDTMesoscale DiscussionSPCBaldwin, Banks, Barrow, Bibb, Bleckley, Bulloch and 54 more83 min
Apr 3, 9:50 AM CDTSevere Thunderstorm WatchSPCBaker, Baldwin, Barrow, Ben Hill, Berrien, Bibb and 92 more7 hr
Apr 3, 12:42 PM CDTMesoscale DiscussionSPCAppling, Bryan, Bulloch, Burke, Candler, Columbia and 24 more63 min
Apr 3, 1:07 PM CDTTornado WatchSPCAppling, Atkinson, Bacon, Baldwin, Bleckley, Bryan and 45 more6 hr
Apr 3, 5:41 PM CDTMesoscale DiscussionSPCChatham, McIntosh64 min

Nearby

Tornado Watches in Alabama, 2017Tornado Watches in Florida, 2017Every tornado watch 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.