Alert archive / Oklahoma / Tornado Warnings in 2011

Tornado Warning 9, NWS Shreveport, LA

April 14, 2011McCurtain County, Oklahoma

NWS Shreveport, LA issued this tornado warning at Apr 14, 2011, 10:30 PM CDT for McCurtain County, Oklahoma. It was in force for 31 min. 2 reports 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: Apr 14, 2011, 10:30 PM CDT (03:30 UTC)
Expired: Apr 14, 2011, 11:01 PM CDT
In force: 31 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon

County McCurtain County, OK

The radar

The Western Arkansas radar (KSRX), 94 km from the middle of the area, began a volume at 03:31 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
Apr 14, 10:33 PM CDT	TORNADO 0	4 Wsw Smithville, OK	AN EF0 TORNADO TOUCHED DOWN NEAR SMITHVILLE OKLAHOMA. THE STORM FIRST TOUCHED DOWN ALONG US 259 WHERE SEVERAL TREES WERE SNAPPED. SOME MINOR ROOF DAMAGE OCCURRED TO A HOME NEARBY. THE TORNADO LIFTED ALONG HWY 4 EAST OF SMITHVILLE. MAXIMUM SUSTAINED WINDS WERE
Apr 14, 10:36 PM CDT	HAIL 1	Watson, OK

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

The watch it was issued in

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

Issued	Product	Office	Lasted
Apr 14, 9:06 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 3.5 hours before the alert went out and 235 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: 1201 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 1314 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 117 m²/s²
0-3 km storm-relative helicity: 135 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 6.5

Open this sounding in Storm Lab

The text

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

392 
WFUS54 KSHV 150330
TORSHV
OKC089-150415-
/O.NEW.KSHV.TO.W.0009.110415T0330Z-110415T0415Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SHREVEPORT LA
1030 PM CDT THU APR 14 2011

THE NATIONAL WEATHER SERVICE IN SHREVEPORT HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN MCCURTAIN COUNTY IN SOUTHEAST OKLAHOMA...

* UNTIL 1115 PM CDT

* AT 1027 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 7 MILES WEST 
OF   SMITHVILLE...MOVING EAST AT 40 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  BEACHTON...WATSON AND PLUNKETVILLE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WARNING MEANS THAT STRONG ROTATION HAS BEEN DETECTED IN THE
STORM. A TORNADO MAY ALREADY BE ON THE GROUND...OR IS EXPECTED TO
DEVELOP SHORTLY. IF YOU ARE IN THE PATH OF THIS DANGEROUS STORM...
MOVE INDOORS AND TO THE LOWEST LEVEL OF THE BUILDING. STAY AWAY FROM
WINDOWS. IF DRIVING...DO NOT SEEK SHELTER UNDER A HIGHWAY OVERPASS.

&&

LAT...LON 3451 9449 3451 9447 3450 9446 3434 9446
      3433 9484 3451 9487 3452 9486 3452 9450
TIME...MOT...LOC 0329Z 263DEG 42KT 3446 9473

$$

06

1 follow-up statement

481 
WWUS54 KSHV 150401
SVSSHV

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1101 PM CDT THU APR 14 2011

OKC089-150410-
/O.CAN.KSHV.TO.W.0009.000000T0000Z-110415T0415Z/
MCCURTAIN OK-
1101 PM CDT THU APR 14 2011

...THE TORNADO WARNING FOR NORTHEAST MCCURTAIN COUNTY IS CANCELLED...

THE SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO IN NORTHEAST
MCCURTAIN COUNTY OKLAHOMA HAS MOVED OUT OF THE AREA.

LAT...LON 3451 9449 3451 9447 3450 9446 3434 9446
      3433 9484 3451 9487 3452 9486 3452 9450
TIME...MOT...LOC 0400Z 263DEG 42KT 3449 9429

$$

06

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 14, 9:46 PM CDT	Severe Thunderstorm Warning	SHV	McCurtain	59 min
Apr 14, 10:48 PM CDT	Tornado Warning	SHV	McCurtain	57 min
Apr 14, 11:34 PM CDT	Severe Thunderstorm Warning	SHV	McCurtain	56 min
Apr 14, 11:37 PM CDT	Tornado Warning	SHV	McCurtain	38 min
Apr 15, 12:26 AM CDT	Severe Thunderstorm Warning	SHV	McCurtain	64 min
Apr 15, 10:14 AM CDT	River Flood Warning	SHV	McCurtain	4 hr

Nearby

Tornado Warnings in Oklahoma, 2011 Every tornado warning in 2011 Tornadoes 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.