Alert archive / Arkansas / Tornado Watches in 2011
Tornado Watch 26
The Storm Prediction Center issued this tornado watch at Feb 27, 2011, 10:04 PM CST for 47 counties in Arkansas; 17 counties in Oklahoma; 5 counties in Texas. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 27, 2011, 10:04 PM CST (04:04 UTC)
- Expired
- Feb 28, 2011, 4:00 AM CST
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 69 counties
Baxter County, AR, Benton County, AR, Boone County, AR, Carroll County, AR, Clark County, AR, Cleburne County, AR, Conway County, AR, Crawford County, AR, Dallas County, AR, Faulkner County, AR, Franklin County, AR, Fulton County, AR, Garland County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Johnson County, AR, Little River County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Miller County, AR, Montgomery County, AR, Nevada County, AR, Newton County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Polk County, AR, Pope County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Sevier County, AR, Sharp County, AR, Stone County, AR, Van Buren County, AR, Washington County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Adair County, OK, Atoka County, OK, Bryan County, OK, Cherokee County, OK, Choctaw County, OK, Delaware County, OK, Haskell County, OK, Latimer County, OK, LeFlore County, OK, Mayes County, OK, McCurtain County, OK, McIntosh County, OK, Muskogee County, OK, Pittsburg County, OK, Pushmataha County, OK, Sequoyah County, OK, Wagoner County, OK, Bowie County, TX, Fannin County, TX, Grayson County, TX, Lamar County, TX, Red River County, TX
The radar
The Western Arkansas radar (KSRX), 2 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
- 30%
- Ten or more severe wind reports
- 60%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
16 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 27, 10:39 PM CST | Severe Thunderstorm Warning | TSA | Washington | 51 min |
| Feb 27, 10:47 PM CST | Severe Thunderstorm Warning | TSA | Adair, Cherokee | 28 min |
| Feb 27, 10:48 PM CST | Severe Thunderstorm Warning | TSA | Crawford, Sebastian | 42 min |
| Feb 27, 10:50 PM CST | Severe Thunderstorm Warning | TSA | Crawford, Franklin | 40 min |
| Feb 27, 10:53 PM CST | Severe Thunderstorm Warning | TSA | Choctaw, Pushmataha | 52 min |
| Feb 27, 11:00 PM CST | Severe Thunderstorm Warning | TSA | Benton, Washington | 30 min |
| Feb 27, 11:27 PM CST | Severe Thunderstorm Warning | TSA | Crawford, Franklin, Sebastian | 48 min |
| Feb 27, 11:28 PM CST | Severe Thunderstorm Warning | TSA | Benton, Carroll, Madison, Washington | 47 min |
| Feb 27, 11:38 PM CST | Severe Thunderstorm Warning | TSA | LeFlore, Pushmataha | 52 min |
| Feb 27, 11:54 PM CST | Severe Thunderstorm Warning | LZK | Boone, Marion | 51 min |
| Feb 28, 12:10 AM CST | Severe Thunderstorm Warning | TSA | Crawford, Franklin, Madison | 32 min |
| Feb 28, 12:20 AM CST | Severe Thunderstorm Warning | LZK | Boone, Johnson, Newton, Pope | 55 min |
| Feb 28, 12:23 AM CST | Severe Thunderstorm Warning | LZK | Baxter, Fulton, Izard | 52 min |
| Feb 28, 1:09 AM CST | Severe Thunderstorm Warning | LZK | Johnson, Pope, Searcy, Van Buren | 51 min |
| Feb 28, 1:15 AM CST | Severe Thunderstorm Warning | LZK | Fulton, Izard, Sharp | 45 min |
| Feb 28, 1:41 AM CST | Severe Thunderstorm Warning | LZK | Baxter, Fulton, Izard, Marion, Searcy, Stone | 49 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
Springfield, MO (KSGF), launched 00:00Z, 4.1 hours before the alert went out and 188 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
- 626 J/kg
- Mixed-layer CIN
- -80 J/kg
- Mixed-layer LCL
- 1011 m above ground
- 0-6 km bulk shear
- 65 kt
- 0-1 km storm-relative helicity
- 369 m²/s²
- 0-3 km storm-relative helicity
- 472 m²/s²
- Significant tornado parameter
- 1.5
- Supercell composite
- 7.4
The text
As transmitted, in the capitals the NWS used until 2016.
501
WWUS20 KWNS 280406
SEL6
SPC WW 280406
ARZ000-OKZ000-TXZ000-281000-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 26
NWS STORM PREDICTION CENTER NORMAN OK
1005 PM CST SUN FEB 27 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
CENTRAL AND WESTERN ARKANSAS
EASTERN OKLAHOMA
FAR NORTHEAST TEXAS
EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 1005 PM UNTIL
400 AM CST.
TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 105 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES WEST NORTHWEST OF
HARRISON ARKANSAS TO 35 MILES SOUTH SOUTHWEST OF DE QUEEN
ARKANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).
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 24...WW 25...
DISCUSSION...TSTMS CONTINUE TO INCREASE IN VICINITY OF THE
DRYLINE/PACIFIC COLD FRONT FROM ECNTRL OK INTO FAR NERN TX. EXPECT
A QLCS WILL EVOLVE THROUGH EARLY MORNING MONDAY AND MATURE OVER
WRN/CNTRL AR. ALTHOUGH THE STORM MODE MAY LARGELY BE LINEAR WITH
EMBEDDED BOWS/LEWPS GIVING CORRIDORS OF HIGH WINDS...POTENTIAL
EXISTS FOR A FEW TORNADOES AS 0-1KM SRH REMAINS QUITE HIGH.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 25040.
...RACY/HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 27, 8:07 PM CST | Mesoscale Discussion | SPC | Crawford, Franklin, Howard, Little River, Logan, Madison and 7 more | 53 min |
| Feb 27, 11:49 PM CST | Mesoscale Discussion | SPC | Clark, Conway, Crawford, Franklin, Garland, Hempstead and 20 more | 86 min |
| Feb 28, 1:05 AM CST | Mesoscale Discussion | SPC | Clay, Craighead, Crittenden, Cross, Greene, Mississippi and 2 more | 25 min |
| Feb 28, 1:33 AM CST | Tornado Watch | SPC | Clay, Craighead, Crittenden, Cross, Greene, Lawrence and 4 more | 7 hr |
| Feb 28, 5:28 AM CST | Mesoscale Discussion | SPC | Ashley, Chicot, Desha, Phillips | 62 min |
| Feb 28, 5:59 AM CST | Tornado Watch | SPC | Lee, Phillips | 7 hr |
| Feb 27, 10:54 PM CST | Mesoscale Discussion | SPC | Anderson, Bell, Bosque, Cherokee, Collin, Coryell and 24 more | 96 min |
Nearby
Tornado Watches in Arkansas, 2011Tornado Watches in Oklahoma, 2011Tornado Watches in Texas, 2011Every tornado watch in 2011
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.