Intense Wind Storm Rakes Northwest Indiana

An intense supercell thunderstorm moved southeastward across Lake and Porter counties in northwest Indiana during the evening hours of Wednesday August 15th. This storm produced an extensive swath of wind damage, some quite significant, stretching from near Gary and East Chicago southeastward through areas near Kouts, IN. An extensive ground damage survery was conducted by the National Weather Service, the results of which can be found in the following write up:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
400 PM CDT THU AUG 16 2007

...INTENSE WIND DAMAGE IN NORTHWEST INDIANA...

SEVERE THUNDERSTORMS BLASTED LAKE AND PORTER COUNTIES WEDNESDAY
EVENING AUGUST 15. THE SEVERE STORM PRODUCED A SWATH OF WIND DAMAGE
RUNNING FROM NORTHWEST LAKE COUNTY AROUND EAST CHICAGO AND
GARY...SOUTHEASTWARD THROUGH AREAS SOUTH OF HOBART AND EAST OF
MERRILLVILLE. THE STORM DAMAGE CONTINUED THROUGH PORTER COUNTY FROM
DEEP RIVER TO LAKE ELIZA TO JUST NORTH OF BOONE GROVE. THE STORM
APPEARED TO REACH MAXIMUM INTENSITY IN SOUTHEAST PORTER COUNTY FROM
JUST NORTH OF KOUTS TO A FEW MILES EAST AND SOUTHEAST OF KOUTS NEAR
THE LAPORTE COUNTY LINE.

THE DAMAGE WAS FAIRLY WIDESPREAD IN A PATH 3 TO 5 MILES WIDE. ALL
DAMAGED TREES AND FLATTENED CORN WERE BLOWN DOWN IN A SOUTHEAST TO
SOUTH DIRECTION...SHOWING NO SIGNS OF SUSTAINED OR ORGANIZED
CIRCULATION. ALTHOUGH THE STORM SHOWED INDICATIONS OF STRONG
ROTATION ON DOPPLER RADAR...IT APPEARS THAT THE CIRCULATION DID NOT
REACH DOWN TO THE GROUND AND THERE WAS NO TORNADO. THE WIND DAMAGE
WAS CAUSED BY INTENSE DOWNDRAFT IN THE REAR FLANK OF THE STORMS
CIRCULATION.

MOST DAMAGE WAS TREE LIMBS BLOWN DOWN BUT THERE WAS ALSO SOME SIGNS
DOWN...GRAIN BINS...MACHINE SHEDS AND OTHER FARM OUTBUILDINGS WITH
ROOF AND DOOR DAMAGE OR TOTAL COLLAPSE. SOME HOMES HAD DAMAGE TO
SHINGLES...GUTTERS AND ANTENNAS BUT THERE WAS NO MAJOR STRUCTURAL
DAMAGE. THE MOST INTENSE DAMAGE WAS IN THE SOUTHEAST PART OF THE
COUNTY JUST EAST OF KOUTS WHERE THERE WERE SWATHS OF INTENSE DAMAGE
TO TREES. LARGE HARDWOOD TREES WERE UPROOTED OR SNAPPED. TWENTY ONE
METAL TRUSS TOWERS FOR POWER LINES WERE KNOCKED DOWN ALONG A 4 TO 5
MILE PATH EAST AND SOUTHEAST OF KOUTS.

WINDS WERE LIKELY 50 TO 70 MPH THROUGH A FAIRLY WIDE SWATH WITH PEAK
WINDS WITH THE MORE INTENSE DAMAGE APPROXIMATELY 100 TO 120 MPH.


$$
ALLSOPP/IZZI

The image below depicts the approximate path of the most extensive wind damage in northwest Indiana.

Radar Image from 9:18 pm CDT from the Romeoville NWS showing the strong hook echo over southern Porter county

Storm Relative Motion at the same time showing the strong rotation in the storm.  The light greenish/light bluish colors show inbound motion toward the Romeoville radar and the red colors show outbound motions away from the radar.  This slice of the storm is at about 4,000 feet above the ground with the highest inbounds at about 75 knots (86mph) and the highest outbounds at about 45 knots (52mph):

Here are some damage pictures taken by the Porter County Emergency Manager:

High tension electrical towers toppled east of Kouts in Porter County.

Closer view of high tension wire tower damage.

Healthy tree snapped off in Porter County

Tree damage to a house and garage in Porter County.

TJH 8/16/07