Tornadoes · United States · Arkansas · 2017

EF1 tornado, Busch to Viola, Arkansas, April 26, 2017

From Busch to Viola, this EF1 tornado ran 15.7 miles across Carroll, Barry and Stone counties on April 26, 2017, touching down at 1:22 AM CDT and reaching 1,500 yards wide. It killed nobody, and did $185,000 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 mphthis tornado

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

  3. EF2111 to 135 mph

    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
EF1
Date
April 26, 2017
Touchdown
1:22 AM CDT (06:22 UTC)
Lifted
1:38 AM CDT (06:38 UTC)
On the ground
16 minutes
Path length
15.7 miles (25.2 km)
Path width
1,500 yards (1372 m)
Deaths
0
Injuries
0
Property damage
$185,000
Counties
Carroll, Barry and Stone counties
Touchdown point
36.438, -93.824
Lift-off point
36.508, -93.552
Record number
1704260022-01

The damage survey

107 damage points were recorded along this path by NWS SGF and NWS TSA, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 107 mph.

  • uprooted trees n, ne, and e

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

What the Weather Service recorded

Severe thunderstorms developed along and ahead of a cold front that moved into eastern Oklahoma during the evening of the 25th. The storms moved eastward across northwestern Arkansas during the early morning hours of the 26th, resulting in one tornado, hail up to quarter size, and damaging wind. Locally heavy rainfall of three to four inches resulted in flash flooding.

Severe storms hit the Missouri Ozarks.

This is the first segment of the three segment tornado. In Carroll County, this tornado snapped and uprooted numerous trees, damaged a number of homes, destroyed outbuildings, and blew down power poles. Based on this damage, maximum estimated wind in this segment of the tornado was 100 to 110 mph. The tornado moved into Barry County, Missouri, and eventually Stone County, Missouri, where it dissipated.

A NWS storm survey confirmed an EF-1 crossed the Arkansas and Missouri border into extreme southeastern Barry County near St. Johns Wood Lane and the Kings River. Numerous trees were snapped or uprooted on a path through a near by hill side across the Kings River. A few trees were blown on to homes in the area. Estimated maximum wind speed was up to 90 mph.

A NWS storm survey found that a tornado continued from Barry County into extreme southwestern Stone County. The tornado was rated an EF-0 in Stone County with estimated max wind speeds up to 80 mph. Numerous trees were uprooted or blown down along the path. The tornado path ended near Highway 86 just east of Highway 39. There were some minor structural damage near the community of Carr Lane.

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 Tulsa, OK wrote its last area forecast discussion before the tornado touched down at Apr 26, 12:17 AM CDT, 1 hour 5 minutes earlier.

Area forecast discussion, Apr 26, 12:17 AM CDT, 1 hour 5 minutes before
Area Forecast Discussion
National Weather Service Tulsa OK
1217 AM CDT Wed Apr 26 2017

.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
Broken line of ongoing convection across Eastern Oklahoma will
continue to shift eastward into Northwest Arkansas overnight
tonight and into Wednesday as a cold front makes its way through
the region. Periods of MVFR conditions will be possible within the
convection. Behind the frontal passage...north to northwesterly
winds along with continued possible showers will be possible into
the afternoon hours Wednesday for Eastern Oklahoma and into the
early evening hours for Northwest Arkansas before exiting the
region Wednesday night. Also behind the front...MVFR conditions
look to spread across the region late tonight and Wednesday with
parts of Northeast Oklahoma possibly lifting back to VFR toward
the end of the TAF period.

&&

.PREV DISCUSSION... /Issued 941 PM CDT Tue Apr 25 2017/

DISCUSSION...
Convection continues to increase in coverage near the frontal
boundary that is moving into northeast Oklahoma at this time. A
few of the storms have been severe, and the severe weather threat
will continue well into the overnight hours as the storms continue
to move off to the east and northeast. Locally heavy rainfall will
also become a concern overnight as multiple storms may train over
the same location. Have raised pops overnight given current
trends. Have also lowered overnight low temperatures given the
magnitude of the cold air spreading south across Kansas behind the
cold front. Temperatures will be slow to rise Wednesday, so also
lowered those high temperatures slightly.

Update on the way.

&&

.PRELIMINARY POINT TEMPS/POPS...
TUL   41  70  56  76 /  10  10  40  30
FSM   42  74  56  82 /  20  10  30  40
MLC   41  74  58  80 /   0  10  10  30
BVO   38  68  51  74 /  10  20  40  30
FYV   39  68  54  76 /  20  10  40  50
BYV   40  68  55  77 /  20  10  30  40
MKO   43  71  56  78 /  10  10  30  40
MIO   37  67  53  75 /  20  10  40  30
F10   44  72  58  75 /  10  10  20  20
HHW   43  75  58  80 /   0  10  10  30

&&

.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Flash Flood Watch through this afternoon for OKZ056>058-060>076.

AR...Flash Flood Watch through this afternoon for ARZ001-002-010-011-
     019-020-029.

&&

AVIATION...20
Hazardous weather outlook, Apr 25, 4:29 PM CDT, 8 hours 53 minutes before
Hazardous Weather Outlook
National Weather Service Tulsa OK
429 PM CDT Tue Apr 25 2017

ARZ001-002-010-011-019-020-029-OKZ049-053>076-261030-
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-
429 PM CDT Tue Apr 25 2017

...ACTIVE WEATHER WEEK BEGINS TONIGHT...

This Outlook is for Northwest and West Central Arkansas as well as
much of Eastern Oklahoma.

.DAY ONE...Today and Tonight.
TORNADO.
	RISK...Limited.
	AREA...Along and northwest of an Okemah to Vinita line.
	ONSET...7-10 PM.

SEVERE THUNDERSTORM.
	RISK...Elevated.
	AREA...Northeast Oklahoma into far Northwest Arkansas before midnight,
			Northwest Arkansas into Southeast Oklahoma after midnight.
	ONSET...After 6 PM.

FLASH FLOOD.
	RISK...Limited.
	AREA...Along and north of I-40.
	ONSET...After 10 PM.

HEAVY RAIN.
	RISK...Limited.
	AREA...Along and north of I-40.
	ONSET...After 10 PM.

DISCUSSION...

An elevated or enhanced risk of severe storms is forecast this
evening and overnight across northeast Oklahoma into far
northwest Arkansas. Large hail in excess of 2 inches in diameter
and wind gusts to 70 mph will be the main threats. Isolated
tornadoes are possible with discrete storms and with any kinks or
bows in the eventual squall line. There is a limited risk of
flooding mainly late this evening into the overnight hours.

Isolated to widely scattered storms are expected to develop by
around 6 or 7 PM to the northwest of Tulsa near a merging dryline
and cold front. These storms are expected to lift northeast into
Kansas. Other storms are expected to develop farther south along
the merging dryline and front over central Oklahoma by 8 or 9 PM.
These storms will move quickly into northeast Oklahoma thru the
evening hours, gradually becoming a line and marching east into far
northwest Arkansas by around midnight. More storms will develop on
the outflow reinforced front over east central Oklahoma into west
central Arkansas after midnight. The severe threat is expected to
wane after midnight, while the flooding risk increases, as the
tendency for storms to train over the same areas increases.

SPOTTER AND EMERGENCY MANAGEMENT ACTION STATEMENT...
Activation of the Regional Spotter Network Likely.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.
WEDNESDAY...Severe Thunderstorm Potential...High Wind Potential...Heavy Rain Potential.
THURSDAY...Thunderstorm Potential.
FRIDAY and SATURDAY...Severe Thunderstorm Potential...Heavy Rain Potential.
SUNDAY and MONDAY...No Hazards.

EXTENDED DISCUSSION...

There will be storms ongoing early Wednesday morning, and
depending on the evolution of the squall line and cold front,
there may be a threat for additional severe storms Wednesday
across mainly far eastern Oklahoma and western Arkansas.

The stormy pattern will continue with additional severe weather
and heavy rain Friday and Saturday. With the approach of
an upper level storm system Friday afternoon...storms will develop
with the potential for large hail...damaging winds and a few
tornadoes. The severe potential will continue into Saturday...but
the main hazard may transition to heavy rain and flooding Saturday
into Sunday. At least 2 to 3 inches of rain is likely...with
localized higher amounts of 5 or 6 inches. This will definitely
cause some flash flooding and river flooding across portions of
the area this weekend.

EMERGENCY MANAGEMENT PLANNING STATEMENT...

An active week of weather is expected across eastern Oklahoma and
western Arkansas. Continue to monitor the latest forecasts and be
prepared for any watches or warnings that may be issued for your
area.

weather.gov/tulsa Contains additional information.

In the hours before

Local storm report, Apr 26, 12:38 AM CDT, 44 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
1238 AM CDT WED APR 26 2017

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

1220 AM     TSTM WND DMG     1 WSW RENTIESVILLE      35.52N 95.51W
04/26/2017                   MCINTOSH           OK   TRAINED SPOTTER

            LARGE HIGHWAY SIGN KNOCKED OVER ON US HIGHWAY 69.

&&

CAS
Local storm report, Apr 26, 12:41 AM CDT, 41 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
1241 AM CDT WED APR 26 2017

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

1235 AM     HAIL             OKTAHA                  35.58N 95.47W
04/26/2017  E1.00 INCH       MUSKOGEE           OK   PUBLIC

            VIA FACEBOOK.

&&

CAS
Special weather statement, Apr 26, 12:57 AM CDT, 25 minutes before
Special Weather Statement
National Weather Service Tulsa OK
1257 AM CDT WED APR 26 2017

OKZ071-073>075-260630-
Haskell OK-Pittsburg OK-Latimer OK-McIntosh OK-
1257 AM CDT WED APR 26 2017

...SIGNIFICANT WEATHER ADVISORY FOR HASKELL...SOUTHEASTERN
MCINTOSH...NORTHWESTERN LATIMER AND PITTSBURG COUNTIES UNTIL 130 AM
CDT...

At 1257 AM CDT, strong thunderstorms were located along a line
extending from 3 miles northeast of Eufaula to 3 miles southwest of
Crowder to 2 miles northeast of Stuart. Movement was east at 35 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
these storms.

Locations in or near the path include...
Mcalester...                      Eufaula...
Stigler...                        Hartshorne...
Krebs...                          Quinton...
Kiowa...                          Savanna...
McCurtain...                      Crowder...
Whitefield...                     Alderson...
Kinta...                          Canadian...
Ashland...                        Haywood...
Mc Curtain...                     Lequire...
Blocker...                        Robbers Cave State Park...

A severe thunderstorm watch remains in effect until 200 AM CDT for
southeastern and east central Oklahoma. A severe thunderstorm watch
also remains in effect until 600 AM CDT for southeastern Oklahoma.

LAT...LON 3498 9609 3509 9579 3535 9556 3531 9535
      3529 9534 3530 9530 3526 9525 3529 9520
      3522 9481 3520 9484 3520 9493 3516 9493
      3496 9533 3468 9574 3473 9609
TIME...MOT...LOC 0557Z 276DEG 32KT 3531 9553 3509 9571 3492 9605

Lacy
Local storm report, Apr 26, 1:04 AM CDT, 18 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
104 AM CDT WED APR 26 2017

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

1257 AM     TSTM WND GST     3 ENE HIGHFILL          36.28N 94.31W
04/26/2017  M61 MPH          BENTON             AR   ASOS

            MEASURED BY ASOS AT NW ARKANSAS REGIONAL AIRPORT.

&&

CAS
Local storm report, Apr 26, 1:13 AM CDT, 9 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
113 AM CDT WED APR 26 2017

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

0111 AM     TSTM WND DMG     1 WSW BENTONVILLE       36.37N 94.23W
04/26/2017                   BENTON             AR   TRAINED SPOTTER

            LARGE TREE LIMBS DOWN...POSSIBLE DAMAGE TO CARPORT.
            ESTIMATED 70 MPH.

&&

CAS
Local storm report, Apr 26, 1:19 AM CDT, 3 minutes before
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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.

Springfield, MO (KSGF), 00:00Z

6.4 hours before the tornado, 49 km from the path. April 26, 2017.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 00:00Z on 2017-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 446 joules per kilogram, CIN -158, lifted condensation level 1525 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, Springfield, MO at 00:00Z on 2017-04-26The 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 122 square meters per square second, 0 to 6 km bulk shear 43 knots.19395878Sfc1 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
446 J/kg
Mixed-layer CIN
-158 J/kg
Surface CAPE
816 J/kg
Mixed-layer LCL
1525 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
14 kt
0-1 km storm-relative helicity
122 m²/s²
0-3 km storm-relative helicity
196 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

Springfield, MO (KSGF), 12:00Z

5.6 hours after it, 49 km from the path. April 26, 2017.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2017-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 25 joules per kilogram, CIN -181, lifted condensation level 579 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, Springfield, MO at 12:00Z on 2017-04-26The 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 174 square meters per square second, 0 to 6 km bulk shear 52 knots.19395878Sfc1 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
25 J/kg
Mixed-layer CIN
-181 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
579 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
174 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0
0-3 km lapse rate
5.2 K/km

Open this sounding in Storm Lab

The surface observations

Branson West Muni (FWB), 36 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 Springfield radar (KSGF), 89 km away, was scanning. The volume nearest the touchdown began at 06:24 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 2017 tornado in ArkansasEvery tornado in Arkansas since 1950Warnings in force in Arkansas nowThe forecast where you are

The other tornadoes of April 26, 2017

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 2610:04 AM CDTEF0Yell, AR0.550$200,000
April 267:12 PM CDTEF1Hickman, KY12.3150$500,000
April 2610:31 PM CDTEF1Leake, MS10.6600$120,000

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.