PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
413 PM CDT THU MAY 15 2014

…NWS DAMAGE SURVEY FOR MAY 11 2014 TORNADO #4…

ADDITIONAL PHOTO AND RADAR EVIDENCE HAS REVEALED THAT A FOURTH
TORNADO BRIEFLY FORMED IN SOUTHEAST BOONE COUNTY ON THE EVENING
OF MAY 11.

.TORNADO #4…

RATING: EF-0
ESTIMATED PEAK WIND: 85 MPH
PATH LENGTH: 1.70 MILES
PATH WIDTH: 50 YARDS (AVG) 100 YARDS (MAX)
FATALITIES: 0
INJURIES: 0

START DATE: MAY 11 2014
START TIME: 10:44 PM CDT
START LOCATION: 3.16 MILES SE OF LUTHER
START LAT/LON: 41.947129, -93.763389

END DATE: MAY 11 2014
END TIME: 10:46 PM CDT
END LOCATION: 1.63 MILES SW OF NAPIER
END_LAT/LON: 41.963004, -93.738490

RADAR IMAGERY…ALONG WITH GROUND AND AERIAL PHOTOS CONFIRM THAT A
BRIEF EF-0 TORNADO FORMED ALONG THE LEADING EDGE OF A QLCS
SOUTHWEST OF AMES ON THE EVENING OF MAY 11. THE TORNADO TRACKED
THROUGH A SHELTER BELT AND FARMSTEAD…CAUSING EXTENSIVE TREE
DAMAGE. ALL OF THE DAMAGE TO THE BUILDINGS ON THE FARMSTEAD APPEAR
TO BE FROM FALLING TREE DEBRIS.

SPECIAL THANKS TO JOHN MCLAUGHLIN FOR AERIAL PHOTOS OF THE TORNADO
DAMAGE AND TRACK.

EF SCALE: THE ENHANCED FUJITA SCALE CLASSIFIES TORNADOES INTO THE
FOLLOWING CATEGORIES.

EF0…WEAK……65 TO 85 MPH
EF1…WEAK……86 TO 110 MPH
EF2…STRONG….111 TO 135 MPH
EF3…STRONG….136 TO 165 MPH
EF4…VIOLENT…166 TO 200 MPH
EF5…VIOLENT…>200 MPH

NOTE:
THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENT AND PUBLICATION IN NWS
STORM DATA.

$$

KS