Tornadoes · United States · Missouri · 2017

EF1 tornado, Brush Creek to Drynob, Missouri, May 27, 2017

From Brush Creek to Drynob, this EF1 tornado ran 9.0 miles across Laclede County on May 27, 2017, touching down at 2:50 PM CDT and reaching 100 yards wide. It killed nobody, and did $100,000 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
May 27, 2017
Touchdown
2:50 PM CDT (19:50 UTC)
Lifted
2:57 PM CDT (19:57 UTC)
On the ground
7 minutes
Path length
9.0 miles (14.5 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
Property damage
$100,000
County
Laclede County
Touchdown point
37.600, -92.722
Lift-off point
37.584, -92.581
Record number
1705271350-01

The damage survey

8 damage points were recorded along this path by NWS SGF, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 104 mph.

  • Photos submitted via local media on social media.

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

Multiple rounds of severe thunderstorms brought damaging straight-line winds, large hail, tornadoes, and flooding to the Missouri Ozarks from May 27th into the early morning hours of May 28th. Over 130 reports of severe weather and flooding were received from the Missouri Ozarks.

The roof of a trucking business near mile mark 123 along I-44 was damaged along with multiple trucks overturned in a parking lot. This tornado uprooted numerous trees and damaged several outbuildings across rural Laclede County.

A NWS storm survey confirmed an EF-1 tornado touched down near the Falcon area in Laclede County. A house sustained moderate to major damage. There were numerous trees snapped and uprooted. Radar confirmed a well defined tornado debris signature over the path of this tornado. Estimated maximum wind speeds were up to 100 mph.

A NWS storm survey confirmed an EF-1 tornado tracked about 2 miles across rural Laclede County near the Drynob area. Numerous trees were uprooted along the path. Estimated maximum wind speed was up to 90 mph.

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

The warnings

5 minutes of warning. NWS SGF issued a tornado warning for this county at 19:45 UTC, 5 minutes before the tornado touched down, in force until 20:15 UTC.

The county was under a tornado watch, issued at 17:16 UTC and running to 23:26 UTC.

Issued (UTC)ExpiredProductOffice
17:16 UTC23:26 UTCTornado WatchSGF
18:00 UTC03:08 UTCFlash Flood WatchSGF
19:33 UTC20:15 UTCSevere Thunderstorm WarningSGF
19:45 UTC20:15 UTCTornado WarningSGF
20:00 UTC21:00 UTCSevere Thunderstorm WarningSGF
20:04 UTC20:30 UTCTornado WarningSGF
20:16 UTC20:45 UTCTornado WarningSGF
23:15 UTC00:00 UTCSevere Thunderstorm WarningSGF
23:26 UTC02:28 UTCSevere Thunderstorm WatchSGF
23:56 UTC00:23 UTCSevere Thunderstorm WarningSGF
23:57 UTC00:33 UTCSevere Thunderstorm WarningSGF

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The forecast that day

The Storm Prediction Center had this point in a Moderate Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 16:19 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

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), 12:00Z

7.8 hours before the tornado, 128 km from the path. May 27, 2017.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2017-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3187 joules per kilogram, CIN -48, lifted condensation level 766 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2017-05-27The 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 127 square meters per square second, 0 to 6 km bulk shear 36 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
3187 J/kg
Mixed-layer CIN
-48 J/kg
Surface CAPE
1824 J/kg
Mixed-layer LCL
766 m above ground
0-6 km bulk shear
36 kt
0-1 km bulk shear
14 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
138 m²/s²
Significant tornado parameter
1.8
Supercell composite
9.6
0-3 km lapse rate
4.4 K/km

Open this sounding in Storm Lab

The radar

The Springfield radar (KSGF), 77 km away, was scanning. The volume nearest the touchdown began at 19:49 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
17:15 UTCHAIL 0.75Saint RobertPulaski, MOPENNY SIZE HAIL. SUBMITTED VIA INTERNET.
17:18 UTCHAIL 1.25Fort Leonard WoodPulaski, MOHALF DOLLAR SIZE HAIL. TIME BASED ON RADAR. REPORT VIA INTERNET.
19:15 UTCHAIL 1.753 Sse BolivarPolk, MOGOLF BALL SIZE HAIL VIA LE.
19:35 UTCTSTM WND DMGPleasant HopePolk, MOTHUNDERSTORM WIND DAMAGE. MULTIPLE LARGE TREES ARE DOWN OUT OF THE GROUND. VIA INTERNET SUBMISSION.
19:42 UTCHAIL 0.881 Nnw BrightonPolk, MOOBSERVER REPORTS NICKLE SIZED HAIL 1 MILE WEST OF 13 HIGHWAY ON 215.
19:45 UTCTSTM WND DMG4 Wsw Osage BeachCamden, MO5 DIAMETER TREE ACROSS ROAD, NICHOLS RD NEAR SYCAMORE GOLF COURSE, OSAGE BEACH. TIME BASED ON RADAR.
19:50 UTCTORNADO4 Ne PhillipsburgLaclede, MONWS STORM SURVEY TEAM CONFIRMED AN EF-1 TORNADO THAT TRACKED FROM APPROXIMATELY 6 MILES SOUTHWEST OF LEBANON TO 6 MILES SOUTHEAST OF LEBANON. THE TORNADO TRACKED APPROXIMATELY 9 MILES WITH A PATH WIDTH OF 100 YARDS. MAXI
19:55 UTCTORNADO2 Sw PhillipsburgLaclede, MOTORNADO. WALL CLOUD WITH ROTATION CROSSING I44. TIME BASED ON RADAR. CONFIRMED DAMAGE BY EM.
19:55 UTCTORNADO2 Sw PhillipsburgLaclede, MOTORNADO. WALL CLOUD WITH ROTATION CROSSING I44. TIME BASED ON RADAR. CONFIRMED DAMAGE BY EM. TRUCKING HUB WITH MULTIPLE OVERTURNED TRUCKS AND MODERATE STRUCTUAL DAMAGE. I44 AND MILE MARKER 123. CORRECTED TO UPDATE INFO.
20:00 UTCTSTM WND DMG5 Ene PhillipsburgLaclede, MOWIND DAMAGE OF TREES SNAPPED OR UPROOTED WITH SEVERAL LARGE TREES UPROOTED AND BROKEN OFF. VIA INTERNET SUBMISSION AT 4:07PM ON MAY 28TH.
20:03 UTCTSTM WND DMGFair GroveGreene, MOFAIR GROVE REPORTS 68 MPH WIND GUSTS AT AT LEAST 1 4INCH TREE DOWN.
20:05 UTCHAIL 11 W StraffordGreene, MO305PM ..QUARTER SIZED HAIL...1 MI W OF STRAFFORD, GREENE COUNTY.
20:09 UTCTORNADO2 W Dry KnobLaclede, MONWS STORM SURVEY TEAM CONFIRMED AN EF-1 TORNADO THAT TRACKED FROM APPROXIMATELY 2 MILES SOUTHWEST OF DRYNOB TO ONE THIRD OF A MILE SOUTH OF DRYNOB. THE TORNADO TRACKED APPROXIMATELY 2 MILES WITH A PATH WIDTH OF 100 YARDS
20:10 UTCHAIL 0.883 Wsw StraffordGreene, MOQUARTER SIZED HAIL REPORTED BY STRAFFORD OFFICER ON I44 BETWEEN SPRINGFIELD AND STRAFFORD.
20:15 UTCHAIL 1.75GrovespringWright, MOGOLF BALL SIZE HAIL WITH SNAPPED TREES.
20:21 UTCTORNADO4 Ese FalconLaclede, MONWS STORM SURVEY REVEALED AN EF-1 TORNADO TOUCHED DOWN 4 MILES EAST SOUTHEAST OF FALCON IN LACLEDE COUNTY. A HOUSE SUSTAINED MAJOR DAMAGE AND NUMEROUS TREES WERE SNAPPED. THIS POINT ALSO CORRESPONDS WITH A WELL DEFINED T
20:25 UTCTORNADO7 Sw Fort Leonard WoodLaclede, MONWS STORM SURVEY TEAM CONFIRMED AN EF-1 TORNADO THAT BRIEFLY TOUCHED DOWN APPROXIMATELY 7 MILES SOUTHWEST OF FORT LEONARD WOOD IN RURAL LACLEDE COUNTY. MAXIMUM WINDS WERE ESTIMATED TO BE 90 MPH. NUMEROUS TREES WERE UPROO
20:30 UTCTSTM WND DMG1 Wsw FalconLaclede, MOTREES SNAPPED OR UPROOTED, MULTIPLE TREES UPROOTED. HAIL .25 TO .50.
20:30 UTCTSTM WND DMG4 N RobyTexas, MOREPORTED AT EVENING SHADE, MO. SEVERAL TREES UPROOTED. VIA SOCIAL MEDIA.
20:45 UTCTSTM WND DMGWaynesvillePulaski, MOTREES UPROOTED AND SHINGLES OFF HOUSE...77.2 MPH MEASURED WINDS...HUNTERS POINT SUBDIVISION IN WAYNESVILLE, PULASKI COUNTY.
20:45 UTCHAIL 1.53 S Saint RobertPulaski, MOPICTURE FROM SOCIAL MEDIA OF PING PONG SIZE HAIL AT FORT LEONARD WOOD.
22:45 UTCHAIL 11 N CamdentonCamden, MO1.00 INCH HAIL OBSERVED BY TRAINED SPOTTER.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2017 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

The other tornadoes of May 27, 2017

13 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 272:38 PM CDTEF1Morgan, MO0.1300$25,000
May 272:38 PM CDTEF1Morgan, MO0.150$50,000
May 273:05 PM CDTEF1Laclede, MO5.0400$100,000
May 273:09 PM CDTEF1Laclede, MO2.1100
May 273:25 PM CDTEF1Laclede, MO0.0100
May 274:00 PM CDTEF0Dent, MO0.050
May 278:18 PM CDTEF0Butler, MO1.985$40,000
May 278:20 PM CDTEF0Okfuskee, OK2.1100
May 278:55 PM CDTUnratedOkfuskee, OK0.6100
May 2710:17 PM CDTUnratedMurray, OK2.850
May 2710:39 PM CDTUnratedJohnston, OK1.550
May 2711:06 PM CDTUnratedJefferson, OK2.5100
May 2711:45 PM CDTEF1Crawford, OK to AR11.2700$30,000

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.