Tornadoes · United States · Oklahoma · 2009

EF2 tornado, Mountain Fork to Ink, Oklahoma, April 9, 2009

From Mountain Fork to Ink, this EF2 tornado ran 10.7 miles across Polk and LeFlore counties on April 9, 2009, touching down at 7:26 PM CDT and reaching 800 yards wide. It killed nobody and injured 4, and did $350,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mph

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. EF186 to 110 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. EF2111 to 135 mphthis tornado

    Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

  4. EF3136 to 165 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. EF4166 to 200 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. EF5over 200 mph

    Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

  7. Unrated

    The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

The record

Rating
EF2
Date
April 9, 2009
Touchdown
7:26 PM CDT (00:26 UTC)
Lifted
7:41 PM CDT (00:41 UTC)
On the ground
15 minutes
Path length
10.7 miles (17.2 km)
Path width
800 yards (732 m)
Deaths
0
Injuries
4
Property damage
$350,000
Counties
Polk and LeFlore counties
Touchdown point
34.619, -94.562
Lift-off point
34.654, -94.384
Record number
0904091826-01

What the Weather Service recorded

Low pressure aloft approached from the west and collided with moisture and instability. Thunderstorms developed in eastern Oklahoma during the afternoon, then became more numerous as they entered western Arkansas during the evening. The storms brought a few tornadoes and numerous hailstorms to Arkansas during the evening hours.

A tornado moved out of Le Flore County, Oklahoma, and entered Polk County, Arkansas, just north of where Oklahoma Highway 63 becomes Arkansas Highway 8 at the state line. A vacation home was destroyed and a 5th-wheel camping trailer was overturned. Hundreds of trees were knocked down in the Ouachita National Forest. Much of the track of the tornado through the forest was inaccessible by road, so aerial imagery from a flyover by the USDA Forest Service was used to determine this portion of the track.

A tornado began to the west-southwest of Mena, then tracked through the northwest side of Mena. According to the Polk County Judge, 165 houses were destroyed, 701 houses had major damage, and more than 11,000 trees were blown down. The Polk County Courthouse, county jail, Mena City Hall, and the police and fire departments were damaged in downtown Mena, as were several businesses. Mena Middle School, also located downtown, was structurally damaged beyond repair. A nursing home was also damaged. Most of the city lost electricity. The tornado then tracked to the northeast, badly damaging several industrial buildings. There was considerable roof damage at Rich Mountain Community College, and lesser damage to the hospital. As the tornado continued to the northeast, a tractor dealership was destroyed. A number of rural residences and farms were damaged as the tornado moved out into rural Polk County. North of Ink, damage was noted along Polk 74 and Polk 71; these same areas had been damaged by a tornado on October 6, 2008. Three fatalities occurred on the northwest side of Mena. One was a woman at a Masonic Lodge, and the others were a man and woman at separate residences.

The deaths

3 direct deaths are recorded for this tornado, each with what Storm Data knows of it.

AgeSexWhereKind
61MPermanent HomeDirect
67FPermanent HomeDirect
84FPermanent StructureDirect

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

What forecasters said that day

The local office's own words before the tornado touched down, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Little Rock, AR wrote its last area forecast discussion before the tornado touched down at Apr 9, 6:21 PM CDT, 1 hour 5 minutes earlier.

Area forecast discussion, Apr 9, 6:21 PM CDT, 1 hour 5 minutes before
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
621 PM CDT THU APR 9 2009

.AVIATION...
THUNDERSTORMS ASSOCIATED WITH DRY LINE AND COLD FRONT WILL MOVE INTO
THE WEST SHORTLY. HAVE TRIED TO TIME CONVECTION AT THE
TERMINALS...WITH MVFR TO IFR CONDITIONS AND GUSTY WINDS. BEHIND THE
FRONT...WINDS WILL SWITCH TO THE WEST/NORTHWEST. UPPER LOW WILL MOVE
OVER NORTHERN ARKANSAS DURING THE MORNING ON FRIDAY...WITH RAIN
CHANCES CONTINUING. MVFR CONDITIONS WILL CONTINUE THROUGH THE
MORNING...BUT WILL BEGIN BREAKING UP OVER THE FOUR SOUTHERN SITES BY
MID DAY.
&&

.PREV DISCUSSION... /ISSUED 224 PM CDT THU APR 9 2009/

DISCUSSION...
MAIN CONCERNS THIS FORECAST CYCLE ARE CHANCES OF CONVECTION...AND
SEVERE POTENTIAL...IN FIRST TO SECOND PERIOD...AS THE STORM MOVES
THROUGH. THEN NEXT CHANCE OF CONVECTION...POSSIBLE SEVERE...LATE
IN THE WEEKEND. WINDS WILL STAY UP WITH A LAKE WIND ADVISORY
AT LEAST THROUGH TONIGHT.

LIGHT CONVECTION HAS BEEN MOVING ACROSS MUCH OF WEST AND NORTHERN
AR THIS MORNING INTO THE AFTERNOON. RAIN AMOUNTS HAVE BEEN JUST A
FEW TENTHS. NOT SEEN MUCH PAST I30 TO 167 AND TO THE EAST. WARM
FRONT WAS LIFTED A BIT MORE NORTH TO NEAR THE AR AND MO STATE
LINE...WITH IMPROVING MOISTURE FLUX OVER THE STATE. EARLY THIS
AFTERNOON TO EVENING...BETTER FOCUS OF SEVERE STORMS WILL BE OUT
WEST...UNTIL THE UPPER DYNAMICS MOVE ACROSS AR LATER THIS EVENING
TO MIDNIGHT. LOW LEVEL MOISTURE INFLUX AND JET FOCUS OVER EASTERN
OK AND NORTHWEST AR AT THIS TIME...AND EXPECT THIS TO GRADUALLY
SHIFT EAST.

SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
WILL START WITH HIGH POPS AND SEVERE MENTION IN FORECAST WITH
EXPECTED TRENDS. QUITE A HOT AND DRY ATMOSPHERE BEHIND THE DRY
LINE OVER NORTHEAST TEXAS...AND AREAS TO EAST WHERE MOISTURE FLUX
AND DYNAMICS CAN MERGE WILL HAVE A GOOD CHANCE OF SEVERE STORMS.
WIND PROFILES WILL BE MORE FAVORABLE A BIT FARTHER NORTH OVER
EASTERN OK INITIALLY...THEN PROGRESSING INTO AR THIS EVENING. ALL
SEVERE HAZARDS WILL BE POSSIBLE WITH WIND...HAIL AND ISOLATED
TORNADOES. MODELS ARE CLOSE WITH TIMING OF THE LOW ACROSS NW AR TO
SOUTHERN MO AROUND 04Z TO 12Z...WITH THE COLD FRONT OVER WESTERN
AR AT 06Z...THEN OVER EASTERN AR AT 12Z. FRIDAY MORNING THE LOW
WILL BE MOVING NORTHEAST...WITH LINGERING CLOUDS AND PRECIP OVER
NORTH TO PARTS OF CENTRAL AR...THEN ENDING IN THE AFTERNOON. DRY
AND COOL FRIDAY NIGHT AND SATURDAY...WITH A BIT COOLER THAN NORMAL
VALUES. THEN LATE SATURDAY AND ON SUNDAY...THE NEXT STORM SYSTEM
AFFECTS AR WITH THE CONTINUING ACTIVE SOUTHERN STREAM. ISOLATED
STRONG TO SEVERE STORMS MAY ALSO BE POSSIBLE. MODELS ARE COMING IN
WITH ELEVATED QPF...EVEN WITH THE SPEED EXPECTED. THE TIMING OF
THIS SYSTEM WILL CHANGE SOME WITH LATER MODELS.

LONG TERM...MONDAY THROUGH THURSDAY
THE UPPER LOW WILL BE CONTINUING ACROSS NORTH ARKANSAS TO BEGIN
THE PERIOD. THIS LOW WILL MOVE THROUGH THE GREAT LAKES TUESDAY AS
AN UPPER RIDGE MOVES INTO THE PLAINS. THE UPPER RIDGE WILL MOVE TO
THE MISSISSIPPI RIVER WEDNESDAY AS A TROUGH DIGS INTO THE
NORTHWEST U.S. A CLOSED LOW WILL MOVE EAST ACROSS THE NORTHERN
GREAT LAKES THURSDAY.

THE ASSOCIATED SURFACE LOW WILL MOVE NORTH OF ARKANSAS MONDAY. WILL
KEEP LIKELY POPS IN FOR MONDAY MORNING WITH THE UPPER LOW.
PRECIPITATION SHOULD DISSIPATE SOUTH TO NORTH AS THE LOW PULLS AWAY.
HIGH PRESSURE AND DRIER AIR MOVE IN FOR TUESDAY. THERE WILL BE
INCREASING MOISTURE OVER THE AREA WEDNESDAY AS LOW PRESSURE
APPROACHES FROM THE WEST AGAIN. PRECIPITATION CHANCES WILL INCREASE
WEDNESDAY NIGHT AND DECREASE THURSDAY. NEAR NORMAL TEMPERATURES CAN
BE EXPECTED THROUGH THE PERIOD.
&&

.LZK WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY UNTIL 1 AM CDT FRIDAY FOR ARKANSAS-BAXTER-
BOONE-BRADLEY-CALHOUN-CLARK-CLEBURNE-CLEVELAND-CONWAY-DALLAS-
DESHA-DREW-FAULKNER-FULTON-GARLAND-GRANT-HOT SPRING-INDEPENDENCE-
IZARD-JACKSON-JEFFERSON-JOHNSON-LINCOLN-LOGAN-LONOKE-MARION-
MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-POLK-POPE-PRAIRIE-
PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN BUREN-WHITE-WOODRUFF-
YELL.
&&

AVIATION...58
Hazardous weather outlook, Apr 9, 4:05 PM CDT, 3 hours 21 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LITTLE ROCK AR
405 PM CDT THU APR 9 2009

ARZ003>007-012>016-021>025-030>034-037>047-052>057-062>069-101000-
ARKANSAS-BAXTER-BOONE-BRADLEY-CALHOUN-CLARK-CLEBURNE-CLEVELAND-
CONWAY-DALLAS-DESHA-DREW-FAULKNER-FULTON-GARLAND-GRANT-HOT SPRING-
INDEPENDENCE-IZARD-JACKSON-JEFFERSON-JOHNSON-LINCOLN-LOGAN-LONOKE-
MARION-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-POLK-POPE-
PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN BUREN-WHITE-
WOODRUFF-YELL-
405 PM CDT THU APR 9 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A LARGE PART OF ARKANSAS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

AN APPROACHING STORM SYSTEM WILL BRING SHOWERS AND THUNDERSTORMS TO
THE STATE THIS AFTERNOON INTO THE OVERNIGHT HOURS...WITH THE
POTENTIAL FOR SEVERE THUNDERSTORMS.

A COLD FRONT ACROSS CENTRAL OKLAHOMA THIS AFTERNOON WILL CONTINUE TO
MOVE EAST DURING THE EVENING HOURS. THUNDERSTORMS WILL DEVELOP ALONG
AND AHEAD OF THIS FRONT. DUE TO THE ENERGY WITH THE SYSTEM...LARGE
HAIL...DAMAGING WINDS AND ISOLATED TORNADOES WILL BE POSSIBLE.

THE BEST CHANCE OF SEVERE WEATHER WILL BE ACROSS THE WESTERN HALF OF
THE STATE...AS MUCH OF THE INSTABILITY WILL BE LOST WITH SUNSET
APPROACHING. HOWEVER...EVEN ACROSS EASTERN ARKANSAS...LARGE HAIL AND
DAMAGING WINDS REMAIN CONCERNS THROUGH THE LATE EVENING AND
OVERNIGHT HOURS.

DUE TO THE STRONG WINDS ASSOCIATED WITH THIS FRONT...A LAKE WIND
ADVISORY IS IN EFFECT THROUGH THE EVENING HOURS...WITH WIND SPEEDS
OF 15 TO 25 MPH COMMON...WITH GUSTS TO 30 MPH.

THE FRONT WILL MOVE THROUGH THE STATE AND BE EAST OF THE MISSISSIPPI
RIVER JUST AFTER SUNRISE FRIDAY.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

RAINFALL WILL CONTINUE ACROSS THE NORTH OF FRIDAY...AS THE UPPER LOW
ASSOCIATED WITH THE SYSTEM MOVES ACROSS THE STATE.

THE NEXT STORM SYSTEM WILL ARRIVE FROM THE SOUTHERN PLAINS EASTER
SUNDAY...AND CONTINUE INTO MONDAY. THERE ARE MANY FACTORS THAT NEED
TO COMBINE TO PRODUCE SEVERE WEATHER...AND THE SEVERE WEATHER
POTENTIAL WILL CONTINUE TO BE MONITORED AS NEW DATA BECOMES
AVAILABLE. HEAVY RAIN WILL ALSO BE A POSSIBILITY WITH THIS SYSTEM.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND THIS EVENING.

&&

VISIT NWS LITTLE ROCK ON THE WEB. GO TO HTTP://WEATHER.GOV AND
CLICK ON CENTRAL ARKANSAS.

58

The air that afternoon

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Shreveport, LA (KSHV), 00:00Z

0.4 hours before the tornado, 249 km from the path. April 10, 2009.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 00:00Z on 2009-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 938 joules per kilogram, CIN -186, lifted condensation level 814 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Shreveport, LA at 00:00Z on 2009-04-10The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 370 square meters per square second, 0 to 6 km bulk shear 52 knots.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
938 J/kg
Mixed-layer CIN
-186 J/kg
Surface CAPE
1584 J/kg
Mixed-layer LCL
814 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
370 m²/s²
0-3 km storm-relative helicity
290 m²/s²
Significant tornado parameter
0.2
Supercell composite
4.5
0-3 km lapse rate
5.8 K/km

Open this sounding in Storm Lab

Shreveport, LA (KSHV), 12:00Z

11.6 hours after it, 249 km from the path. April 10, 2009.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2009-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 698 joules per kilogram, CIN -122, lifted condensation level 737 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Shreveport, LA at 12:00Z on 2009-04-10The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 128 square meters per square second, 0 to 6 km bulk shear 73 knots.1939587897117Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
698 J/kg
Mixed-layer CIN
-122 J/kg
Surface CAPE
1327 J/kg
Mixed-layer LCL
737 m above ground
0-6 km bulk shear
73 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
213 m²/s²
Significant tornado parameter
0.4
Supercell composite
4.2
0-3 km lapse rate
5.9 K/km

Open this sounding in Storm Lab

The surface observations

Mena Intermountain Municipal (MEZ), 27 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

From the Iowa Environmental Mesonet's archive of airport observations.

The radar

The Western Arkansas radar (KSRX), 73 km away, was scanning. The volume nearest the touchdown began at 00:26 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

This ground now

The live radar over the trackEvery 2009 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of April 9, 2009

21 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 96:03 PM CDTEF0Craig, OK2.4100$25,000
April 96:18 PM CDTEF0Latimer, OK4.3150$100,000
April 96:42 PM CDTEF1Pushmataha, OK7.7200
April 96:55 PM CDTEF1LeFlore, OK7.5400$20,000
April 97:52 PM CDTEF1Morris, TX5.8150$20,000
April 98:01 PM CDTEF3Sevier, OK to AR37.28507$5.1 million
April 98:02 PM CDTEF3Polk, AR14.81,075330$130 million
April 98:05 PM CDTEF2Cass, TX16.8190$750,000
April 98:20 PM CDTEF0Christian, MO1.6150$100,000
April 98:34 PM CDTEF2Howard, AR2.72501$500,000
April 98:41 PM CDTEF0Cass, TX3.875$50,000
April 98:51 PM CDTEF3Miller, AR9.9850$1.0 million
April 98:53 PM CDTEF1Pike, AR3.0350$25,000
April 99:13 PM CDTEF1Harrison, TX2.6200$1.0 million
April 99:48 PM CDTEF2Harrison, TX to LA37.25002$13 million
April 910:02 PM CDTEF0Bossier Parish, LA0.875$5,000
April 911:04 PM CDTEF0Webster Parish, LA2.3100$100,000
April 911:21 PM CDTEF1Union Parish, LA5.5150
April 911:27 PM CDTEF2Ashley, AR13.6600$600,000
April 911:33 PM CDTEF1Lincoln Parish, LA4.4150$300,000
April 912:05 AM CDTEF2Jackson Parish, LA12.6300$1.0 million

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.