Alert archive / Arkansas / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 286, NWS Tulsa, OK

May 12, 2011Crawford County, Sebastian County, Arkansas; Sequoyah County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at May 12, 2011, 6:37 PM CDT for Crawford County, Sebastian County, Arkansas; Sequoyah County, Oklahoma. It was in force for 53 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 12, 2011, 6:37 PM CDT (23:37 UTC)
Expired: May 12, 2011, 7:30 PM CDT
In force: 53 min
Issued by: NWS Tulsa, OK
Area: Storm-based polygon

Counties Crawford County, AR, Sebastian County, AR, Sequoyah County, OK

The radar

The Western Arkansas radar (KSRX), 20 km from the middle of the area, began a volume at 23:37 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 was reported inside it

Time	Report	Where	Remark
May 12, 7:10 PM CDT	HAIL 1.75	Natural Dam, AR

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 33 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 12, 3:17 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 11.6 hours before the alert went out and 170 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1317 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 180 m²/s²
0-3 km storm-relative helicity: 134 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

756 
WUUS54 KTSA 122337
SVRTSA
ARC033-131-OKC135-130030-
/O.NEW.KTSA.SV.W.0286.110512T2337Z-110513T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
637 PM CDT THU MAY 12 2011

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN SEQUOYAH COUNTY IN EAST CENTRAL OKLAHOMA
  CRAWFORD COUNTY IN NORTHWEST ARKANSAS
  NORTHERN SEBASTIAN COUNTY IN WEST CENTRAL ARKANSAS

* UNTIL 730 PM CDT

* AT 632 PM CDT...SEVERE THUNDERSTORMS WERE LOCATED ALONG A LINE
  EXTENDING FROM 12 MILES WEST OF SHORT TO 6 MILES NORTH OF GANS TO 6
  MILES SOUTHWEST OF GANS...MOVING EAST AT 35 MPH.

  STORM HAZARDS INCLUDE...
  QUARTER SIZE HAIL...
  WIND GUSTS TO 60 MPH...

* SOME LOCATIONS IN OR NEAR THE PATH OF THESE STORMS INCLUDE...
  MULDROW...SHORT...ROLAND...MOFFETT...NATURAL DAM...CEDARVILLE...
  FORT SMITH...FIGURE FIVE...VAN BUREN...RUDY...ALMA...CHESTER...
  MOUNTAINBURG AND DYER.

THIS INCLUDES INTERSTATE 40 IN OKLAHOMA BETWEEN MILE MARKERS 311 AND
328.

THIS INCLUDES INTERSTATE 40 IN ARKANSAS BETWEEN MILE MARKERS 0 AND
20.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PEOPLE OUTSIDE SHOULD MOVE TO A SAFE SHELTER...PREFERABLY INSIDE A
STRONG BUILDING. STAY AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

&&

LAT...LON 3538 9410 3536 9443 3537 9444 3537 9447
      3535 9449 3534 9472 3536 9475 3563 9469
      3564 9448 3566 9447 3571 9407
TIME...MOT...LOC 2337Z 272DEG 29KT 3562 9464 3547 9465
          3532 9472

$$

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at May 12, 6:24 PM CDT, 13 minutes earlier.

Area forecast discussion, May 12, 6:24 PM CDT, 13 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
624 PM CDT THU MAY 12 2011

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
FOR THE 0Z TAFS... NUMEROUS THUNDERSTORMS WITH HEAVY RAINFALL AND
MANY WITH LARGE HAIL WILL CONTINUE TO MOVE ACROSS THE REGION THIS
EVENING. KBVO WILL NOT BE AFFECTED. KTUL AND KRVS SHOULD BE OUT OF
THE PRECIP BY ABOUT 1Z. THE REMAINDER OF OUR TAF SITES WILL LIKELY
EXPERIENCE SOME OF THIS ACTIVITY DURING THE EVENING HOURS.

&&

.PREV DISCUSSION... /ISSUED 406 PM CDT THU MAY 12 2011/

DISCUSSION...
CURRENTLY...SCATTERED SHOWERS AND THUNDERSTORMS ARE BEGINNING TO
DEVELOP AND SPREAD ACROSS THE CWA THIS AFTERNOON AHEAD OF A COLD
FRONT LOCATED OVER WEST CENTRAL OKLAHOMA. THIS ACTIVITY WILL BE
THE MAIN CONCERN WITHIN THE FORECAST PACKAGE.

STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE THROUGH THE
AFTERNOON AND EVENING AHEAD OF THE APPROACHING COLD FRONT. STEEP
MID- LEVEL LAPSE RATES AND SLIGHTLY BETTER SHEER THAN YESTERDAY
WITHIN THE WARM SECTOR WILL ALLOW FOR ALL MODE OF SEVERE WEATHER
TO BE POSSIBLE. A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE
CWA UNTIL 3Z.

THE COLD FRONT IS EXPECTED TO MOVE INTO NORTHEAST OKLAHOMA THIS
EVENING...REACHING WESTERN ARKANSAS EARLY FRIDAY MORNING.
THUNDERSTORMS WILL REMAIN POSSIBLE ALONG AND AHEAD OF THE
FRONT...WHILE RAIN SHOWERS WILL BE MORE CAPABLE BEHIND THE
BOUNDARY DURING THE DAY FRIDAY. CHANCES OF SHOWERS WILL CONTINUE
THROUGH FRIDAY NIGHT OVER NORTHWEST ARKANSAS AS THE BACK SIDE OF
THE UPPER LEVEL TROF EXITS TO THE EAST.

BELOW NORMAL TEMPS ARE FORECASTED ON THE BACK SIDE OF THIS SYSTEM
WITH HIGHS IN THE 60S FOR HIGH THROUGH THE WEEKEND AND INTO THE
START OF THE NEXT WORK WEEK. WENT WITH A BLEND OF THE GUIDANCE
TEMPS WITHIN THE SHORT TERM. MODELS CONTINUE TO INDICATE A
SECONDARY WAVE MOVING OFF THE EXITING TROF AND ROTATING BACK CLOSE
TO THE CWA SUNDAY NIGHT AND MONDAY. WILL CONTINUE A DRY FORECAST
FOR THE LATE WEEKEND AND THE START OF NEXT WEEK AS MOST OF THE
ENERGY ASSOCIATED WITH THE WAVE LOOKS TO REMAIN TO THE NORTHEAST
OF THE REGION.

WITHIN THE EXTENDED FORECAST PACKAGE...A RIDGE SETS UP OVER THE
SOUTHERN PLAINS FOR TUESDAY INTO WEDNESDAY. THIS SHOULD ALLOW FOR
TEMPS TO REBOUND BACK INTO THE 70S FOR HIGHS. STAYED CLOSER TO THE
ECMWF FOR TEMPS THROUGH THIS TIME PERIOD. MODELS CONTINUE TO
BIFURCATE ON TIMING AND LOCATION OF A SHORTWAVE TRYING TO DEVELOP
OVER THE LEE OF THE ROCKY MOUNTAINS...SPREADING PRECIP TOWARDS THE
CWA. CURRENT THINKING WILL BE TO CONTINUE POPS FOR THE SECOND HALF
OF THE WEEK...THOUGH WILL JUST USE A BROAD BRUSH OF SLIGHT POPS.

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&

AVIATION...06

Hazardous weather outlook, May 12, 6:15 PM CDT, 22 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
615 PM CDT THU MAY 12 2011

ARZ001-002-010-011-019-020-029-OKZ049-053>076-131000-
ADAIR OK-BENTON AR-CARROLL AR-CHEROKEE OK-CHOCTAW OK-CRAIG OK-
CRAWFORD AR-CREEK OK-DELAWARE OK-FRANKLIN AR-HASKELL OK-LATIMER OK-
LE FLORE OK-MADISON AR-MAYES OK-MCINTOSH OK-MUSKOGEE OK-NOWATA OK-
OKFUSKEE OK-OKMULGEE OK-OSAGE OK-OTTAWA OK-PAWNEE OK-PITTSBURG OK-
PUSHMATAHA OK-ROGERS OK-SEBASTIAN AR-SEQUOYAH OK-TULSA OK-WAGONER OK-
WASHINGTON OK-WASHINGTON AR-
615 PM CDT THU MAY 12 2011

...HAIL TO THE SIZE OF BASEBALLS POSSIBLE THIS EVENING...

THIS OUTLOOK IS FOR NORTHWEST AND WEST CENTRAL ARKANSAS AS WELL AS
MUCH OF EASTERN OKLAHOMA.

.DAY ONE...THIS EVENING AND TONIGHT.
TORNADO.
	RISK...LIMITED.
	AREA...EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

SEVERE THUNDERSTORM.
	RISK...CRITICAL.
	AREA...EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

	AREA AT GREATEST RISK...SOUTH OF EAST OF INTERSTATE 44.

FLASH FLOOD.
	RISK...LIMITED.
	AREA...EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

HEAVY RAIN.
	RISK...LIMITED.
	AREA...EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.
	ONSET...ONGOING.

DISCUSSION...
SCATTERED SEVERE THUNDERSTORMS HAVE DEVELOPED ACROSS EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS...MAINLY ALONG AND EAST OF
THE INTERSTATE 44 CORRIDOR. THE MAIN THREAT FROM THESE STORMS
WILL BE LARGE HAIL TO THE SIZE OF BASEBALLS. SOME OF THE STORMS
WILL BECOME SUPERCELLULAR EARLY THIS EVENING AND WILL HAVE THE
POTENTIAL TO PRODUCE A TORNADO. THE THUNDERSTORMS MAY CONGEAL INTO
A LINE LATER THIS EVENING WITH THE THREAT FOR DAMAGING WINDS BECOMING
MORE OF A CONCERN. THE THREAT FOR THUNDERSTORMS WILL END LATE TONIGHT
AS A COLD FRONT SWEEPS THROUGH THE AREA.

LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE THROUGH THE
EVENING...AND MAY POSE A RISK OF ISOLATED FLASH FLOODING
ACROSS FAR EASTERN OKLAHOMA AND NORTHWEST ARKANSAS WHERE
STORM COVERAGE WILL BE HIGHEST.

SPOTTER AND EMERGENCY MANAGEMENT ACTION STATEMENT...
ACTIVATION OF THE REGIONAL SPOTTER NETWORK EXPECTED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.
FRIDAY...THUNDERSTORM POTENTIAL.
SATURDAY THROUGH MONDAY...NO HAZARDS.
TUESDAY AND WEDNESDAY...THUNDERSTORM POTENTIAL.

EXTENDED DISCUSSION...
ISOLATED THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS FAR
NORTHWEST ARKANSAS ON FRIDAY...THOUGH SEVERE WEATHER
IS NOT EXPECTED.  DRY AND COOL WEATHER WILL PREVAIL
THROUGH THE WEEKEND...WITH INCREASING THUNDERSTORM
CHANCES FOR EARLY NEXT WEEK.

WWW.SRH.NOAA.GOV/TULSA CONTAINS ADDITIONAL INFORMATION.

In the hours before

Local storm report, May 12, 6:13 PM CDT, 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
613 PM CDT THU MAY 12 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0607 PM     HAIL             AFTON                   36.69N 94.96W
05/12/2011  M2.50 INCH       OTTAWA             OK   TRAINED SPOTTER

            BROKEN WINDSHIELDS

&&

PBS

Local storm report, May 12, 6:14 PM CDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
614 PM CDT THU MAY 12 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0613 PM     HAIL             SALLISAW                35.46N 94.79W
05/12/2011  M2.00 INCH       SEQUOYAH           OK   AMATEUR RADIO

&&

PBS

Local storm report, May 12, 6:17 PM CDT, 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
617 PM CDT THU MAY 12 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0611 PM     HAIL             SALLISAW                35.46N 94.79W
05/12/2011  E2.50 INCH       SEQUOYAH           OK   BROADCAST MEDIA

&&

PBS

Local storm report, May 12, 6:28 PM CDT, 9 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
628 PM CDT THU MAY 12 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0626 PM     HAIL             WYANDOTTE               36.79N 94.72W
05/12/2011  E2.00 INCH       OTTAWA             OK   LAW ENFORCEMENT

&&

PBS

Local storm report, May 12, 6:33 PM CDT, 4 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
633 PM CDT THU MAY 12 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0556 PM     HAIL             AFTON                   36.69N 94.96W
05/12/2011  M2.50 INCH       OTTAWA             OK   TRAINED SPOTTER

            GOLFBALL AND TENNIS BALL SIZE HAIL BROKE WINDSHIELDS

0605 PM     HAIL             1 SSW BARON             35.91N 94.62W
05/12/2011  E0.88 INCH       ADAIR              OK   TRAINED SPOTTER

&&

EJC

Local storm report, May 12, 6:37 PM CDT, 0 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
637 PM CDT THU MAY 12 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0605 PM     HAIL             2 ESE SALLISAW          35.45N 94.75W
05/12/2011  E1.25 INCH       SEQUOYAH           OK   TRAINED SPOTTER

&&

EJC

The office that day

Everything else NWS Tulsa, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 11, 7:25 PM CDT	Severe Thunderstorm Warning	TSA	Benton, Carroll, Madison, Washington	44 min
May 11, 7:34 PM CDT	Special Weather Statement	TSA	Franklin	56 min
May 11, 7:48 PM CDT	Special Weather Statement	TSA	Franklin	27 min
May 11, 8:11 PM CDT	Severe Thunderstorm Warning	TSA	Madison	24 min
May 12, 5:39 PM CDT	Severe Thunderstorm Warning	TSA	Crawford	51 min
May 12, 5:56 PM CDT	Severe Thunderstorm Warning	TSA	Crawford	64 min
May 12, 6:13 PM CDT	Severe Thunderstorm Warning	TSA	Madison, Washington	47 min
May 12, 6:18 PM CDT	Severe Thunderstorm Warning	TSA	Crawford, Washington	42 min
May 12, 6:30 PM CDT	Severe Thunderstorm Warning	TSA	Madison, Washington	45 min
May 12, 6:39 PM CDT	Areal Flood Advisory	TSA	Benton, Carroll, Crawford, Madison, Washington	66 min
May 12, 6:46 PM CDT	Special Weather Statement	TSA	Carroll	29 min
May 12, 6:52 PM CDT	Severe Thunderstorm Warning	TSA	Crawford, Washington	28 min
May 11, 7:12 PM CDT	Special Weather Statement	TSA	Ottawa	33 min
May 12, 3:55 PM CDT	Special Weather Statement	TSA	Pittsburg	35 min
May 12, 4:04 PM CDT	Severe Thunderstorm Warning	TSA	Pittsburg	41 min
May 12, 4:33 PM CDT	Special Weather Statement	TSA	Craig	42 min
May 12, 4:41 PM CDT	Severe Thunderstorm Warning	TSA	Craig	64 min
May 12, 4:44 PM CDT	Special Weather Statement	TSA	McIntosh, Pittsburg	61 min
May 12, 4:45 PM CDT	Special Weather Statement	TSA	Mayes	30 min
May 12, 4:50 PM CDT	Severe Thunderstorm Warning	TSA	Craig, Mayes, Rogers	40 min
May 12, 4:51 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Pittsburg	39 min
May 12, 4:56 PM CDT	Areal Flood Advisory	TSA	McIntosh, Pittsburg	3 hr
May 12, 5:04 PM CDT	Special Weather Statement	TSA	Sequoyah	56 min
May 12, 5:08 PM CDT	Severe Thunderstorm Warning	TSA	Haskell, LeFlore, Sequoyah	52 min
May 12, 5:09 PM CDT	Special Weather Statement	TSA	Creek	51 min
May 12, 5:12 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okfuskee, Okmulgee	63 min
May 12, 5:15 PM CDT	Special Weather Statement	TSA	Adair	60 min
May 12, 5:17 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Pittsburg	58 min
May 12, 5:24 PM CDT	Severe Thunderstorm Warning	TSA	Cherokee, Haskell, McIntosh, Muskogee, Sequoyah	51 min
May 12, 5:25 PM CDT	Severe Thunderstorm Warning	TSA	Craig, Delaware, Mayes, Ottawa	50 min
May 12, 5:27 PM CDT	Severe Thunderstorm Warning	TSA	McIntosh, Muskogee	48 min
May 12, 5:36 PM CDT	Severe Thunderstorm Warning	TSA	Craig, Ottawa	24 min
May 12, 5:44 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Cherokee	46 min
May 12, 5:45 PM CDT	Severe Thunderstorm Warning	TSA	Haskell, McIntosh, Muskogee, Sequoyah	45 min
May 12, 5:56 PM CDT	Severe Thunderstorm Warning	TSA	Creek, Okmulgee, Tulsa, Wagoner	49 min
May 12, 6:00 PM CDT	Severe Thunderstorm Warning	TSA	Rogers, Tulsa, Wagoner	45 min
May 12, 6:07 PM CDT	Areal Flood Advisory	TSA	Haskell, McIntosh, Muskogee, Pittsburg, Sequoyah	3 hr
May 12, 6:07 PM CDT	Severe Thunderstorm Warning	TSA	Delaware, Ottawa	38 min
May 12, 6:11 PM CDT	Special Weather Statement	TSA	Atoka	34 min
May 12, 6:11 PM CDT	Severe Thunderstorm Warning	TSA	Adair, Cherokee, Haskell, LeFlore, Muskogee, Sequoyah	64 min
May 12, 6:14 PM CDT	Severe Thunderstorm Warning	TSA	Choctaw	31 min
May 12, 6:15 PM CDT	Severe Thunderstorm Warning	TSA	Cherokee, Mayes, Muskogee, Rogers, Tulsa, Wagoner	45 min
May 12, 6:23 PM CDT	Severe Thunderstorm Warning	TSA	Pushmataha	52 min
May 12, 6:41 PM CDT	Special Weather Statement	TSA	LeFlore	34 min
May 12, 6:47 PM CDT	Severe Thunderstorm Warning	TSA	Ottawa	28 min
May 12, 6:50 PM CDT	Severe Thunderstorm Warning	TSA	Choctaw, Pushmataha	24 min
May 12, 6:54 PM CDT	Severe Thunderstorm Warning	TSA	LeFlore	36 min

Nearby

Severe Thunderstorm Warnings in Arkansas, 2011 Severe Thunderstorm Warnings in Oklahoma, 2011 Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.