Alert archive / Alabama / Tornado Watches in 2018

Tornado Watch 48

April 14, 201828 counties in Alabama; Escambia County, Santa Rosa County, Florida; 7 counties in Mississippi

The Storm Prediction Center issued this tornado watch at Apr 14, 2018, 10:36 AM CDT for 28 counties in Alabama; Escambia County, Santa Rosa County, Florida; 7 counties in Mississippi. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Apr 14, 2018, 10:36 AM CDT (15:36 UTC)
Expired
Apr 14, 2018, 7:00 PM CDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
65 kt
All 37 counties

Autauga County, AL, Baldwin County, AL, Bibb County, AL, Blount County, AL, Butler County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Dallas County, AL, Escambia County, AL, Fayette County, AL, Greene County, AL, Hale County, AL, Jefferson County, AL, Lamar County, AL, Lowndes County, AL, Marengo County, AL, Mobile County, AL, Monroe County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, Sumter County, AL, Tuscaloosa County, AL, Walker County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Santa Rosa County, FL, George County, MS, Greene County, MS, Harrison County, MS, Jackson County, MS, Perry County, MS, Stone County, MS, Wayne County, MS

The radar

The Birmingham radar (KBMX), 99 km from the middle of the area, began a volume at 15:39 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
50%
One or more EF2 to EF5 tornadoes
30%
Ten or more severe wind reports
70%
One or more gusts of 65 knots or more
30%
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
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 14, 10:58 AM CDTSevere Thunderstorm WarningMOBGreene, Perry, Wayne62 min
Apr 14, 11:08 AM CDTSevere Thunderstorm WarningBMXLamar, Pickens56 min
Apr 14, 11:22 AM CDTSevere Thunderstorm WarningBMXSumter43 min
Apr 14, 11:36 AM CDTTornado WarningBMXFayette, Lamar24 min
Apr 14, 11:50 AM CDTSevere Thunderstorm WarningMOBPerry, Stone55 min
Apr 14, 11:53 AM CDTSevere Thunderstorm WarningBMXFayette, Marion52 min
Apr 14, 11:55 AM CDTSevere Thunderstorm WarningBMXGreene, Pickens65 min
Apr 14, 11:59 AM CDTSevere Thunderstorm WarningMOBChoctaw, Clarke, Washington61 min
Apr 14, 12:05 PM CDTTornado WarningBMXGreene, Pickens25 min
Apr 14, 12:24 PM CDTSevere Thunderstorm WarningBMXTuscaloosa81 min
Apr 14, 12:34 PM CDTTornado WarningBMXWalker, Winston20 min
Apr 14, 12:41 PM CDTTornado WarningBMXTuscaloosa13 min
Apr 14, 1:07 PM CDTTornado WarningBMXHale16 min
Apr 14, 1:25 PM CDTFlash Flood WarningLIXHancock, Harrison, Jackson9 hr
Apr 14, 1:39 PM CDTSevere Thunderstorm WarningBMXBibb, Dallas, Hale, Marengo, Perry41 min
Apr 14, 1:50 PM CDTFlash Flood WarningMOBPerry, Stone6 hr
Apr 14, 1:54 PM CDTFlash Flood WarningMOBGreene, Perry, Wayne6 hr
Apr 14, 2:06 PM CDTTornado WarningLIXHarrison11 min
Apr 14, 2:35 PM CDTFlash Flood WarningMOBChoctaw, Washington6 hr
Apr 14, 3:46 PM CDTFlash Flood WarningMOBClarke, Washington6 hr
Apr 14, 3:50 PM CDTFlash Flood WarningMOBGeorge, Greene, Perry, Stone6 hr
Apr 14, 4:53 PM CDTFlash Flood WarningMOBWashington6 hr
Apr 14, 5:33 PM CDTFlash Flood WarningBMXDallas, Marengo, Perry4 hr
Apr 14, 6:14 PM CDTFlash Flood WarningMOBClarke, Washington, Wilcox6 hr
Apr 14, 6:16 PM CDTTornado WarningLIXJackson29 min
Apr 14, 6:57 PM CDTSevere Thunderstorm WarningMOBMobile20 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, 3.6 hours before the alert went out and 100 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 2018-04-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 224 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 2018-04-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 275 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
224 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
560 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
275 m²/s²
0-3 km storm-relative helicity
324 m²/s²
Significant tornado parameter
0.3
Supercell composite
3.7

Open this sounding in Storm Lab

The text

As transmitted.

484 
WWUS20 KWNS 141534
SEL8  
SPC WW 141534
ALZ000-FLZ000-MSZ000-CWZ000-150000-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 48
NWS Storm Prediction Center Norman OK
1030 AM CDT Sat Apr 14 2018

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  southwest through central Alabama
  western Florida Panhandle
  southeast Mississippi
  Coastal Waters

* Effective this Saturday morning and evening from 1030 AM until
  700 PM CDT.

* Primary threats include...
  A few tornadoes and a couple intense tornadoes possible
  Scattered damaging winds likely with isolated significant gusts
    to 75 mph possible

SUMMARY...Squall line will continue to pose a risk for locally
strong to damaging wind gusts and a few tornadoes as it moves
through the Gulf Coast states this afternoon.

The tornado watch area is approximately along and 70 statute miles
east and west of a line from 20 miles north of Birmingham AL to 40
miles south southwest of Mobile AL. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU8).

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 47...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 1.5 inches. Extreme turbulence and surface wind
gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 25030.

...Dial

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 14, 4:35 AM CDTMesoscale DiscussionSPCColbert, Fayette, Franklin, Lamar, Lauderdale, Marion and 1 more115 min
Apr 14, 6:37 AM CDTMesoscale DiscussionSPCSumter83 min
Apr 14, 9:40 AM CDTMesoscale DiscussionSPCAutauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 18 more95 min
Apr 14, 12:41 PM CDTMesoscale DiscussionSPCAutauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 18 more94 min
Apr 14, 2:56 PM CDTMesoscale DiscussionSPCAutauga, Chilton, Coosa, Dallas, Lowndes, Mobile and 5 more94 min
Apr 14, 6:17 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Conecuh, Covington, Escambia and 2 more118 min
Apr 14, 6:55 PM CDTTornado WatchSPCBaldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 7 more6 hr
Apr 13, 7:22 PM CDTTornado WatchSPCAdams, Bolivar, Claiborne, Franklin, Issaquena, Jefferson and 4 more3 hr
Apr 13, 10:12 PM CDTTornado WatchSPCAdams, Alcorn, Benton, Bolivar, Calhoun, Carroll and 33 more10 hr
Apr 14, 2:10 AM CDTMesoscale DiscussionSPCAdams, Attala, Benton, Bolivar, Calhoun, Carroll and 32 more2 hr
Apr 14, 6:57 AM CDTTornado WatchSPCAmite, Attala, Choctaw, Clarke, Clay, Copiah and 30 more7 hr

Nearby

Tornado Watches in Alabama, 2018Tornado Watches in Mississippi, 2018Tornado Watches in Florida, 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.