Alert archive / Oklahoma / Tornado Watches in 2021
Tornado Watch 526
The Storm Prediction Center issued this tornado watch at Oct 12, 2021, 11:05 PM CDT for 25 counties in Oklahoma; 10 counties in Texas. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 12, 2021, 11:05 PM CDT (04:05 UTC)
- Expired
- Oct 13, 2021, 6:00 AM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 65 kt
All 35 counties
Alfalfa County, OK, Beaver County, OK, Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Garfield County, OK, Grant County, OK, Greer County, OK, Harmon County, OK, Harper County, OK, Jackson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, Major County, OK, Noble County, OK, Roger Mills County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Childress County, TX, Collingsworth County, TX, Donley County, TX, Gray County, TX, Hall County, TX, Hemphill County, TX, Lipscomb County, TX, Ochiltree County, TX, Roberts County, TX, Wheeler County, TX
The radar
The Vance AFB radar (KVNX), 103 km from the middle of the area, began a volume at 04:07 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
- 70%
- One or more gusts of 65 knots or more
- 40%
- Ten or more severe hail reports
- 20%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 12, 11:59 PM CDT | Severe Thunderstorm Warning | AMA | Beaver | 61 min |
| Oct 13, 12:01 AM CDT | Severe Thunderstorm Warning | AMA | Gray, Hemphill, Roberts, Wheeler | 59 min |
| Oct 13, 12:14 AM CDT | Severe Thunderstorm Warning | OUN | Ellis, Harper, Woods, Woodward | 61 min |
| Oct 13, 12:38 AM CDT | Severe Thunderstorm Warning | OUN | Ellis, Roger Mills, Woodward | 67 min |
| Oct 13, 12:50 AM CDT | Severe Thunderstorm Warning | AMA | Collingsworth, Donley, Gray, Hemphill, Wheeler | 55 min |
| Oct 13, 12:57 AM CDT | Tornado Warning | AMA | Collingsworth, Donley, Gray, Wheeler | 33 min |
| Oct 13, 1:14 AM CDT | Severe Thunderstorm Warning | OUN | Ellis, Harper, Major, Woods, Woodward | 61 min |
| Oct 13, 1:44 AM CDT | Severe Thunderstorm Warning | OUN | Beckham, Custer, Dewey, Roger Mills | 46 min |
| Oct 13, 2:02 AM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Woods | 29 min |
| Oct 13, 4:25 AM CDT | Severe Thunderstorm Warning | OUN | Kay | 39 min |
| Oct 13, 5:07 AM CDT | Tornado Warning | OUN | Canadian, Oklahoma | 23 min |
| Oct 13, 5:44 AM CDT | Tornado Warning | OUN | Lincoln, Logan, Oklahoma | 18 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
Norman, OK (KOUN), launched 00:00Z, 4.1 hours before the alert went out and 152 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
- 496 J/kg
- Mixed-layer CIN
- -164 J/kg
- Mixed-layer LCL
- 662 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 331 m²/s²
- 0-3 km storm-relative helicity
- 372 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.5
The text
As transmitted.
749
WWUS20 KWNS 130403
SEL6
SPC WW 130403
OKZ000-TXZ000-131100-
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 526
NWS Storm Prediction Center Norman OK
1105 PM CDT Tue Oct 12 2021
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Western and Northern Oklahoma
Northwest Texas
* Effective this Tuesday night and Wednesday morning from 1105 PM
until 600 AM CDT.
* Primary threats include...
A few tornadoes possible
Scattered damaging winds likely with isolated significant gusts
to 75 mph possible
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Broken quasi-linear clusters of storms will move
east-northeastward across the region overnight. Damaging winds will
be possible through the overnight/early morning hours. A few mostly
brief tornadoes will also be a possibility given the unseasonably
high moisture content and robust low-level shear.
The tornado watch area is approximately along and 85 statute miles
east and west of a line from 15 miles north northwest of Alva OK to
20 miles west southwest of Altus OK. 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 522...WW 523...WW
524...WW 525...
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 550. Mean
storm motion vector 22035.
...GuyerSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 12, 7:30 PM CDT | Mesoscale Discussion | SPC | Beaver, Beckham, Caddo, Comanche, Cotton, Custer and 10 more | 2 hr |
| Oct 12, 9:18 PM CDT | Mesoscale Discussion | SPC | Beaver, Beckham, Blaine, Caddo, Canadian, Comanche and 12 more | 117 min |
| Oct 13, 1:18 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Custer, Dewey, Ellis and 7 more | 87 min |
| Oct 13, 3:26 AM CDT | Mesoscale Discussion | SPC | Blaine, Caddo, Canadian, Garfield, Grant, Jackson and 6 more | 94 min |
| Oct 13, 5:16 AM CDT | Mesoscale Discussion | SPC | Cleveland, Creek, Grady, Lincoln, Logan, McClain and 9 more | 59 min |
| Oct 13, 7:34 AM CDT | Mesoscale Discussion | SPC | Cherokee, Craig, Delaware, Hughes, McIntosh, Mayes and 9 more | 116 min |
| Oct 13, 3:59 PM CDT | Mesoscale Discussion | SPC | Brown, Coleman, Collin, Comanche, Cooke, Denton and 9 more | 91 min |
Nearby
Tornado Watches in Oklahoma, 2021Tornado Watches in Texas, 2021Every tornado watch in 2021
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.