Alert archive / Alabama / Tornado Watches in 2017
Tornado Watch 11
The Storm Prediction Center issued this tornado watch at Jan 21, 2017, 3:56 AM CST for 42 counties in Alabama; 5 counties in Florida. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 21, 2017, 3:56 AM CST (09:56 UTC)
- Expired
- Jan 21, 2017, 12:00 PM CST
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 47 counties
Autauga County, AL, Baldwin County, AL, Barbour County, AL, Bibb County, AL, Bullock County, AL, Butler County, AL, Chambers County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Clay County, AL, Coffee County, AL, Conecuh County, AL, Coosa County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Dallas County, AL, Elmore County, AL, Escambia County, AL, Geneva County, AL, Greene County, AL, Hale County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Marengo County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pike County, AL, Randolph County, AL, Russell County, AL, Shelby County, AL, Sumter County, AL, Talladega County, AL, Tallapoosa County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Holmes County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL
The radar
The Birmingham radar (KBMX), 122 km from the middle of the area, began a volume at 09:59 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
- 20%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 20%
- 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
- 80%
Warnings issued inside it
30 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 21, 4:19 AM CST | Severe Thunderstorm Warning | BMX | Lowndes | 41 min |
| Jan 21, 4:24 AM CST | Tornado Warning | MOB | Choctaw, Washington | 51 min |
| Jan 21, 4:52 AM CST | Tornado Warning | MOB | Choctaw | 38 min |
| Jan 21, 5:06 AM CST | Tornado Warning | MOB | Choctaw, Clarke | 39 min |
| Jan 21, 5:21 AM CST | Tornado Warning | BMX | Marengo | 54 min |
| Jan 21, 5:45 AM CST | Severe Thunderstorm Warning | MOB | Clarke, Wilcox | 34 min |
| Jan 21, 7:02 AM CST | Tornado Warning | BMX | Autauga, Lowndes | 43 min |
| Jan 21, 7:02 AM CST | Tornado Warning | MOB | Mobile | 22 min |
| Jan 21, 7:22 AM CST | Severe Thunderstorm Warning | MOB | Baldwin, Mobile | 38 min |
| Jan 21, 7:24 AM CST | Severe Thunderstorm Warning | BMX | Lowndes, Montgomery | 51 min |
| Jan 21, 7:37 AM CST | Severe Thunderstorm Warning | BMX | Elmore | 38 min |
| Jan 21, 7:52 AM CST | Tornado Warning | BMX | Elmore | 38 min |
| Jan 21, 7:58 AM CST | Tornado Warning | BMX | Elmore | 32 min |
| Jan 21, 8:07 AM CST | Severe Thunderstorm Warning | BMX | Coosa | 23 min |
| Jan 21, 8:18 AM CST | Severe Thunderstorm Warning | MOB | Butler, Conecuh, Covington, Crenshaw | 42 min |
| Jan 21, 8:22 AM CST | Tornado Warning | BMX | Coosa, Elmore, Lee, Macon, Tallapoosa | 53 min |
| Jan 21, 8:41 AM CST | Tornado Warning | BMX | Chambers, Lee, Macon | 47 min |
| Jan 21, 8:47 AM CST | Severe Thunderstorm Warning | BMX | Pike | 43 min |
| Jan 21, 8:58 AM CST | Tornado Warning | BMX | Pike | 47 min |
| Jan 21, 8:58 AM CST | Severe Thunderstorm Warning | TAE | Coffee, Dale | 47 min |
| Jan 21, 9:19 AM CST | Severe Thunderstorm Warning | TAE | Geneva, Houston | 41 min |
| Jan 21, 9:21 AM CST | Severe Thunderstorm Warning | MOB | Covington | 39 min |
| Jan 21, 9:23 AM CST | Tornado Warning | BMX | Barbour | 52 min |
| Jan 21, 9:25 AM CST | Severe Thunderstorm Warning | MOB | Okaloosa | 50 min |
| Jan 21, 9:40 AM CST | Severe Thunderstorm Warning | TAE | Dale, Henry | 50 min |
| Jan 21, 9:56 AM CST | Severe Thunderstorm Warning | MOB | Okaloosa | 34 min |
| Jan 21, 10:00 AM CST | Severe Thunderstorm Warning | TAE | Coffee, Dale, Geneva, Henry, Houston | 45 min |
| Jan 21, 10:28 AM CST | Severe Thunderstorm Warning | MOB | Okaloosa | 32 min |
| Jan 21, 10:31 AM CST | Tornado Warning | TAE | Holmes, Walton, Washington | 29 min |
| Jan 21, 10:55 AM CST | Severe Thunderstorm Warning | TAE | Houston | 35 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 00:00Z, 9.9 hours before the alert went out and 123 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.
- Mixed-layer CAPE
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1088 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 115 m²/s²
- 0-3 km storm-relative helicity
- 103 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
679 WWUS20 KWNS 210955 SEL1 SPC WW 210955 ALZ000-FLZ000-CWZ000-211700- URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 11 NWS Storm Prediction Center Norman OK 355 AM CST Sat Jan 21 2017 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central and southern Alabama The western Florida Panhandle Coastal Waters * Effective this Saturday morning from 355 AM until 1100 AM CST. * Primary threats include... A few tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...A large complex of thunderstorms will spread east-northeastward from Mississippi into Alabama through the morning hours. Embedded supercells will be possible with an associated risk for a few tornadoes, damaging winds, and large hail. The tornado watch area is approximately along and 105 statute miles north and south of a line from 50 miles north of Mobile AL to 25 miles southeast of Auburn AL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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 10... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24040. ...Thompson
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 21, 3:00 AM CST | Mesoscale Discussion | SPC | Autauga, Baldwin, Barbour, Bibb, Bullock, Butler and 36 more | 90 min |
| Jan 21, 7:41 AM CST | Mesoscale Discussion | SPC | Autauga, Baldwin, Barbour, Bullock, Butler, Chambers and 24 more | 94 min |
| Jan 21, 9:19 AM CST | Mesoscale Discussion | SPC | Barbour, Coffee, Dale, Geneva, Henry, Houston and 1 more | 86 min |
| Jan 21, 8:04 AM CST | Tornado Watch | SPC | Bay, Calhoun, Gadsden, Gulf, Jackson, Liberty and 1 more | 6 hr |
| Jan 21, 12:06 PM CST | Mesoscale Discussion | SPC | Bay, Calhoun, Gadsden, Gulf, Hamilton, Jackson and 6 more | 114 min |
| Jan 21, 1:12 PM CST | Tornado Watch | SPC | Bay, Calhoun, Franklin, Gadsden, Gulf, Jefferson and 3 more | 5 hr |
| Jan 21, 3:03 PM CST | Mesoscale Discussion | SPC | Baker, Columbia, Franklin, Gilchrist, Gulf, Hamilton and 9 more | 57 min |
| Jan 21, 5:05 PM CST | Mesoscale Discussion | SPC | Bay, Calhoun, Franklin, Gulf, Jefferson, Leon and 4 more | 55 min |
| Jan 21, 12:51 PM CST | Tornado Watch | SPC | Appling, Atkinson, Bacon, Bryan, Bulloch, Burke and 19 more | 4 hr |
| Jan 21, 2:06 PM CST | Mesoscale Discussion | SPC | Appling, Atkinson, Bacon, Brantley, Bryan, Bulloch and 20 more | 84 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.