Tornadoes · United States · Colorado · 2012

EF0 tornado, Yoder, Colorado, April 26, 2012

Name: EF0 tornado, Yoder, Colorado, April 26, 2012
Start: 2012-04-27T01:31:00.000Z
End: 2012-04-27T01:33:00.000Z
Location: Yoder, Colorado

This EF0 tornado ran 0.3 miles across El Paso County on April 26, 2012, touching down at 7:31 PM MDT and reaching 20 yards wide. It killed nobody, and did $10,000 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.

EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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: EF0
Date: April 26, 2012
Touchdown: 7:31 PM MDT (01:31 UTC)
Lifted: 7:33 PM MDT (01:33 UTC)
On the ground: 2 minutes
Path length: 0.3 miles (0.6 km)
Path width: 20 yards (18 m)
Deaths: 0
Injuries: 0
Property damage: $10,000
County: El Paso County
Touchdown point: 38.780, -104.270
Lift-off point: 38.785, -104.271
Record number: 1204261931-01

What the Weather Service recorded

An intense low pressure area produced severe weather across the Peaks Peak Region and far southeastern Colorado. A brief tornado was observed in El Paso County...while hail up to golf ball size was noted over portions of Prowers and Baca Counties.

The EF0 tornado damaged a 30-foot barn and scattered pieces of metal roofing. In addition, the tornado picked up 6-inch diameter cedar posts.

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 Pueblo, CO wrote its last area forecast discussion before the tornado touched down at Apr 26, 5:26 PM MDT, 2 hours 5 minutes earlier.

Area forecast discussion, Apr 26, 5:26 PM MDT, 2 hours 5 minutes before

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Hazardous weather outlook, Apr 26, 10:36 AM MDT, 8 hours 55 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PUEBLO CO
1036 AM MDT THU APR 26 2012

COZ058>089-093>099-271645-
WESTERN MOSQUITO RANGE/EAST LAKE COUNTY ABOVE 11000 FT-
LEADVILLE VICINITY/LAKE COUNTY BELOW 11000 FT-
EASTERN SAWATCH MOUNTAINS ABOVE 11000 FT-
WESTERN CHAFFEE COUNTY BETWEEN 9000 AND 11000 FT-
CENTRAL CHAFFEE COUNTY BELOW 9000 FT-
WESTERN MOSQUITO RANGE/EAST CHAFFEE COUNTY ABOVE 9000 FT-
SAGUACHE COUNTY WEST OF CONTINENTAL DIVIDE BELOW 10000 FT-
SAGUACHE COUNTY EAST OF CONTINENTAL DIVIDE BELOW 10000 FT-
LA GARITA MOUNTAINS ABOVE 10000 FT-
UPPER RIO GRANDE VALLEY/EASTERN SAN JUAN MOUNTAINS BELOW 10000 FT-
EASTERN SAN JUAN MOUNTAINS ABOVE 10000 FT-
DEL NORTE VICINITY/NORTHERN SAN LUIS VALLEY BELOW 8500 FT-
ALAMOSA VICINITY/CENTRAL SAN LUIS VALLEY BELOW 8500 FT-
SOUTHERN SAN LUIS VALLEY-
NORTHERN SANGRE DE CRISTO MOUNTAINS BETWEEN 8500 AND 11000 FT-
NORTHERN SANGRE DE CRISTO MOUNTAINS ABOVE 11000 FEET-
SOUTHERN SANGRE DE CRISTO MOUNTAINS BETWEEN 7500 AND 11000 FT-
SOUTHERN SANGRE DE CRISTO MOUNTAINS ABOVE 11000 FT-
NORTHWESTERN FREMONT COUNTY ABOVE 8500 FT-
WESTERN/CENTRAL FREMONT COUNTY BELOW 8500 FT-
WET MOUNTAIN VALLEY BELOW 8500 FEET-
WET MOUNTAINS BETWEEN 6300 AND 10000 FT-
WET MOUNTAINS ABOVE 10000 FT-
TELLER COUNTY/RAMPART RANGE ABOVE 7500 FT/PIKES PEAK BETWEEN
7500 AND 11000 FT-PIKES PEAK ABOVE 11000 FT-
CANON CITY VICINITY/EASTERN FREMONT COUNTY-
NORTHERN EL PASO COUNTY/MONUMENT RIDGE/RAMPART RANGE BELOW
7500 FT-
COLORADO SPRINGS VICINITY/SOUTHERN EL PASO COUNTY/RAMPART RANGE
BELOW 7400 FT-PUEBLO AND VICINITY/PUEBLO COUNTY BELOW 6300 FT-
WALSENBURG VICINITY/UPPER HUERFANO RIVER BASIN BELOW 7500 FT-
TRINIDAD VICINITY/WESTERN LAS ANIMAS COUNTY BELOW 7500 FT-
CROWLEY COUNTY-LA JUNTA VICINITY/OTERO COUNTY-
EASTERN LAS ANIMAS COUNTY-WESTERN KIOWA COUNTY-
EASTERN KIOWA COUNTY-LAS ANIMAS VICINITY/BENT COUNTY-
LAMAR VICINITY/PROWERS COUNTY-SPRINGFIELD VICINITY/BACA COUNTY-
1036 AM MDT THU APR 26 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL...EAST
CENTRAL...SOUTH CENTRAL AND SOUTHEAST COLORADO.

.DAY ONE...TODAY AND TONIGHT

SEVERAL SEVERE THUNDERSTORMS WILL BE POSSIBLE ACROSS THE SOUTHEAST
PLAINS OF COLORADO THIS AFTERNOON AND TONIGHT. THE AREA WITH THE GREATEST
RISK FOR SEVERE THUNDERSTORMS WILL EXTEND EAST OF A LINE FROM
LIMON...TO LA JUNTA...TO KIM AFTER 1 TO 2 PM...AND CONTINUING
THROUGH 2 AM. THE PRIMARY STORM THREATS THIS AFTERNOON WILL BE
HAIL UP TO 1.5 INCHES IN DIAMETER...AS WELL AS WIND GUSTS UP TO 60
MPH...LOCALLY HEAVY RAINFALL AND LIGHTNING. HOWEVER...AS ANOTHER WAVE OF
SCATTERED TO NUMEROUS THUNDERSTORMS SPREADS OFF THE SOUTHEAST
MOUNTAINS AND ACROSS THE PLAINS DURING THE LATE EVENING AND
OVERNIGHT HOURS...THESE STORMS WILL HAVE THE POTENTIAL TO
ENCOUNTER GREATER INSTABILITY AND WIND SHEAR FAVORABLE FOR THE
PRODUCTION OF LARGE HAIL AROUND 2 INCHES IN DIAMETER OR
GREATER...WIND GUSTS OVER 60 MPH...AND EVEN AN ISOLATED TORNADO.
THE MOST FAVORABLE WINDOW FOR THIS SECOND WAVE OF SEVERE
THUNDERSTORMS WILL BE FROM 9 PM TO 2 AM. RESIDENTS IN SOUTHEAST
COLORADO...PRIMARILY IN KIOWA...BENT...PROWERS...AND BACA
COUNTIES...SHOULD REMAIN ALERT TONIGHT FOR THE POSSIBILITY OF SEVERE
THUNDERSTORMS WITH THE POTENTIAL FOR AN ISOLATED TORNADO DURING
THE EVENING AND OVERNIGHT HOURS.

THE REMAINDER OF SOUTHERN COLORADO WILL ALSO SEE SCATTERED TO
NUMEROUS AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. THE MAIN
THREAT WITH THESE WILL BE HAIL UNDER 1 INCH IN DIAMETER...WIND
GUSTS TO AROUND 50 MPH...AND LIGHTNING.

SNOW WILL FALL ACROSS THE HIGHER ELEVATIONS THIS AFTERNOON THROUGH
TONIGHT. ELEVATIONS ABOVE 10000 FEET CAN EXPECT 2 TO 6 INCHES OF
SNOW BY FRIDAY MORNING WITH LESS THAN 2 INCHES OF SNOW FALLING
BELOW 10000 FEET.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

LIGHT SNOW ACCUMULATIONS OF UP TO A COUPLE OF INCHES WILL BE
POSSIBLE ACROSS THE HIGHEST TERRAIN...GENERALLY ABOVE TEN THOUSAND
FEET...THROUGH THE DAY ON FRIDAY AND AGAIN SATURDAY AFTERNOON AND
SATURDAY NIGHT.

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
ACROSS THE REGION SUNDAY...WITH ISOLATED THUNDERSTORMS POSSIBLE
ACROSS MAINLY THE HIGHER TERRAIN MONDAY THROUGH WEDNESDAY. THE
MAIN THREATS FROM THESE STORMS AREA EXPECTED TO BE LIGHTNING AND
GUSTY WINDS.

.SPOTTER INFORMATION STATEMENT...

WEATHER CONDITIONS THAT MEET REPORTING CRITERIA FOR SPOTTERS WILL BE
LIKELY OVER MUCH OF SOUTH CENTRAL AND SOUTHEAST COLORADO THIS
AFTERNOON AND TONIGHT.

31/40

In the hours before

Local storm report, Apr 26, 5:26 PM MDT, 2 hours 5 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PUEBLO CO
526 PM MDT THU APR 26 2012

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

0517 PM     HAIL             10 NE TWO BUTTES        37.66N 102.27W
04/26/2012  M1.75 INCH       PROWERS            CO   BROADCAST MEDIA

&&

EPETERSE

Special weather statement, Apr 26, 5:41 PM MDT, 1 hour 50 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PUEBLO CO
541 PM MDT THU APR 26 2012

COZ065>067-069-070-270045-
ALAMOSA VICINITY/CENTRAL SAN LUIS VALLEY BELOW 8500 FT-DEL NORTE
VICINITY/NORTHERN SAN LUIS VALLEY BELOW 8500 FT-LA GARITA MOUNTAINS
ABOVE 10000 FT-SAQUACHE COUNTY EAST OF CONTINENTAL DIVIDE BELOW 10000
FT-UPPER RIO GRANDE VALLEY/EASTERN SAN JUAN MOUNTAINS BELOW 10000 FT-
541 PM MDT THU APR 26 2012

...THE NATIONAL WEATHER SERVICE IN PUEBLO HAS ISSUED A SIGNIFICANT
WEATHER ADVISORY FOR...

  SOUTH CENTRAL SAGUACHE COUNTY IN CENTRAL COLORADO
  NORTHWESTERN ALAMOSA COUNTY IN SOUTH CENTRAL COLORADO
  NORTHEASTERN RIO GRANDE COUNTY IN SOUTH CENTRAL COLORADO

STRONG HEATING OF THE GROUND AND THE RESULTING UNSTABLE ATMOSPHERE
CAN CAUSE STRONG DUST DEVILS TO FORM. WINDS COULD APPROACH 60 MPH IN
THE STRONGEST DUST DEVILS...WHICH COULD DAMAGE WEAKER STRUCTURES AND
SANDBLAST ANYTHING IN THEIR PATH.

OCCASIONALLY...DUST DEVILS MOVE INTO AN AREA OF UPDRAFTS OF RAPIDLY
BUILDING CLOUDS. THE RESULT CAN BE AN INTENSIFICATION OF THE DUST
DEVIL CIRCULATION...WHICH DEVELOPS INTO A SHORT-LIVED TORNADO.

IF YOU SEE A STRONG DUST DEVIL APPROACHING...GO TO SHELTER IN A
BUILDING OR VEHICLE. DO NOT DRIVE INTO DUST DEVILS. THE RAPID CHANGE
IN WINDS COULD CAUSE YOU TO LOSE CONTROL OF YOUR VEHICLE...AND COULD
DAMAGE THE EXTERIOR OF YOUR VEHICLE...OR CAUSE TEMPERED GLASS WINDOWS
TO SHATTER.

Special weather statement, Apr 26, 6:01 PM MDT, 1 hour 30 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PUEBLO CO
601 PM MDT THU APR 26 2012

COZ069-072-073-078-270030-
DEL NORTE VICINITY/NORTHERN SAN LUIS VALLEY BELOW 8500 FT-NORTHERN
SANGRE DE CHRISTO MOUNTAINS BETWEEN 8500 AND 11000 FT-NORTHERN SANGRE
DE CRISTO MOUNTAINS ABOVE 11000 FT-WET MOUNTAIN VALLEY BELOW 8500 FT-
601 PM MDT THU APR 26 2012

...THE NATIONAL WEATHER SERVICE IN PUEBLO HAS ISSUED A SIGNIFICANT
WEATHER ADVISORY FOR...

  SOUTHWESTERN FREMONT COUNTY IN CENTRAL COLORADO...
  EAST CENTRAL SAGUACHE COUNTY IN CENTRAL COLORADO...
  NORTHWESTERN CUSTER COUNTY IN SOUTHEAST COLORADO...

AT 555 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CRESTONE...OR 38 MILES NORTH OF ALAMOSA...
WHICH WAS MOVING TOWARD THE NORTHEAST AT 35 MPH.

THE STRONG STORM WILL IMPACT MAINLY RURAL AREAS OF SOUTHWESTERN
FREMONT COUNTY...EAST CENTRAL SAGUACHE COUNTY AND NORTHWESTERN CUSTER
COUNTY.

WINDS AROUND 50 MPH AND BLOWING DUST CAN BE EXPECTED WELL AHEAD OF
THIS STORM...ESPECIALLY OVER THE EXTREME NORTHERN PORTIONS OF THE
SAN LUIS VALLEY.

BE PREPARED TO TAKE SHELTER IN THE EVENT THESE STORMS INTENSIFY AND
BECOME SEVERE...OR A WARNING IS ISSUED BY THE NATIONAL WEATHER
SERVICE.

Local storm report, Apr 26, 6:14 PM MDT, 1 hour 17 minutes before

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Special weather statement, Apr 26, 6:32 PM MDT, 59 minutes before

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Local storm report, Apr 26, 7:06 PM MDT, 25 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.

Denver, CO (KDNR), 00:00Z

1.5 hours before the tornado, 150 km from the path. April 27, 2012.

Skew-T log-p

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.

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. 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: 95 J/kg
Mixed-layer CIN: -85 J/kg
Surface CAPE: 571 J/kg
Mixed-layer LCL: 2538 m above ground
0-6 km bulk shear: 28 kt
0-1 km bulk shear: 13 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 175 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0
0-3 km lapse rate: 8.7 K/km

Open this sounding in Storm Lab

The surface observations

Ellicott-B Afa (ABH), 4 km from the path, in the two hours either side.

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

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

The radar

The Pueblo radar (KPUX), 37 km away, was scanning. The volume nearest the touchdown began at 01:32 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 track Every 2012 tornado in Colorado Every tornado in Colorado since 1950 Warnings in force in Colorado now The forecast where you are

The other tornadoes of April 26, 2012

2 more were confirmed in the United States that day.

Date	Time	Rating	Where	Path (mi)	Width (yd)	Deaths	Injuries	Damage
April 26	6:44 PM CDT	EF2	Chester, TN	1.9	200		1	$400,000
April 26	7:00 PM CDT	EF0	Williamson, TN	3.8	100		6	$75,000

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.