Alert archive / Texas / Tornado Watches in 2021
Tornado Watch 520
The Storm Prediction Center issued this tornado watch at Oct 10, 2021, 11:07 PM CDT for 4 states. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 10, 2021, 11:07 PM CDT (04:07 UTC)
- Expired
- Oct 11, 2021, 4:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 65 kt
All 34 counties
Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Logan County, AR, Miller County, AR, Montgomery County, AR, Pike County, AR, Polk County, AR, Scott County, AR, Sevier County, AR, Yell County, AR, Bossier Parish, LA, Caddo Parish, LA, De Soto Parish, LA, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Morris County, TX, Nacogdoches County, TX, Panola County, TX, Red River County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Wood County, TX
The radar
The Shreveport radar (KSHV), 128 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
- 60%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 10, 11:24 PM CDT | Severe Thunderstorm Warning | SHV | McCurtain | 66 min |
| Oct 10, 11:35 PM CDT | Severe Thunderstorm Warning | SHV | Camp, Franklin, Smith, Titus, Upshur, Wood | 55 min |
| Oct 10, 11:50 PM CDT | Tornado Warning | SHV | McCurtain | 40 min |
| Oct 11, 12:26 AM CDT | Severe Thunderstorm Warning | SHV | Howard, Little River, Miller, Sevier | 64 min |
| Oct 11, 12:32 AM CDT | Severe Thunderstorm Warning | LZK | Polk, Scott | 58 min |
| Oct 11, 12:33 AM CDT | Severe Thunderstorm Warning | SHV | Camp, Cass, Franklin, Gregg, Harrison, Marion and 6 more | 57 min |
| Oct 11, 1:03 AM CDT | Severe Thunderstorm Warning | SHV | Howard | 27 min |
| Oct 11, 1:25 AM CDT | Severe Thunderstorm Warning | LZK | Montgomery, Pike, Polk | 65 min |
| Oct 11, 1:29 AM CDT | Severe Thunderstorm Warning | SHV | Howard, Sevier | 31 min |
| Oct 11, 1:35 AM CDT | Severe Thunderstorm Warning | SHV | Cherokee, Rusk, Smith | 25 min |
| Oct 11, 2:49 AM CDT | Severe Thunderstorm Warning | LZK | Garland, Montgomery | 26 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
Shreveport, LA (KSHV), launched 00:00Z, 4.1 hours before the alert went out and 128 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
- 193 J/kg
- Mixed-layer CIN
- -245 J/kg
- Mixed-layer LCL
- 1467 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 101 m²/s²
- 0-3 km storm-relative helicity
- 188 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
982
WWUS20 KWNS 110403
SEL0
SPC WW 110403
ARZ000-LAZ000-OKZ000-TXZ000-110900-
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 520
NWS Storm Prediction Center Norman OK
1100 PM CDT Sun Oct 10 2021
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Western Arkansas
Northwest Louisiana
Southeast Oklahoma
Northeast Texas
* Effective this Sunday night and Monday morning from 1100 PM
until 400 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...Line of storms with embedded bowing segments and
mesovortices will continue east through northeast TX and into the
Arklatex region tonight. Damaging wind and a few tornadoes are the
main threats.
The tornado watch area is approximately along and 65 statute miles
east and west of a line from 55 miles north of De Queen AR to 55
miles south of Longview TX. For a complete depiction of the watch
see the associated watch outline update (WOUS64 KWNS WOU0).
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 518...WW 519...
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 27040.
...DialSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 10, 9:24 PM CDT | Tornado Watch | SPC | Benton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more | 5 hr |
| Oct 10, 10:16 PM CDT | Mesoscale Discussion | SPC | Little River, Polk, Sevier | 59 min |
| Oct 10, 11:32 PM CDT | Mesoscale Discussion | SPC | Benton, Crawford, Polk, Scott, Sebastian, Sevier and 1 more | 118 min |
| Oct 11, 12:58 AM CDT | Mesoscale Discussion | SPC | Hempstead, Howard, Lafayette, Little River, Logan, Miller and 5 more | 92 min |
| Oct 11, 1:26 AM CDT | Mesoscale Discussion | SPC | Benton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more | 64 min |
| Oct 10, 7:19 PM CDT | Mesoscale Discussion | SPC | Nowata, Washington | 86 min |
| Oct 10, 8:11 PM CDT | Mesoscale Discussion | SPC | Atoka, Bryan, Carter, Coal, Johnston, Love and 1 more | 64 min |
Nearby
Tornado Watches in Texas, 2021Tornado Watches in Arkansas, 2021Tornado Watches in Louisiana, 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.