July 20th, 2011 Severe Thunderstorms

July 20th, 2011
Severe Thunderstorms

A severe thunderstorm struck Darke County Ohio in the early evening of July 20, 2011. Storm damage occurred between Union City and Greenville. A storm survey was conducted by the National Weather Service.

PUBLIC INFORMATION STATEMENT...UPDATED
NATIONAL WEATHER SERVICE WILMINGTON OH
325 PM EDT FRI JUL 22 2011

...MICROBURST /STRAIGHT LINE WIND DAMAGE/ CONFIRMED 
4 SE OF UNION CITY IN DARKE COUNTY OHIO...

LOCATION...4 SE OF UNION CITY IN DARKE COUNTY OHIO
DATE...JULY 20 2011
ESTIMATED TIME...622 PM EDT
ESTIMATED MAXIMUM WIND SPEED...90 MPH
MAXIMUM PATH WIDTH...0.8 MILES
PATH LENGTH...1.5 MILES
BEGINNING LAT/LON...40.1801N/84.7543W
ENDING LAT/LON...40.1656N/84.7323W
* FATALITIES...0
* INJURIES...0

* THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENT(S) AND PUBLICATION IN NWS
STORM DATA.

...SUMMARY...
THE NATIONAL WEATHER SERVICE IN WILMINGTON OH HAS CONFIRMED A
MICROBURST /STRAIGHT LINE WIND DAMAGE/ 4 SE OF UNION CITY IN DARKE
COUNTY OHIO ON JULY 20 2011.

DAMAGE FROM STRAIGHT LINE WINDS WAS EVIDENT ACROSS THIS AREA. BARNS 
WERE DAMAGED EXTENSIVELY BY A MICROBURST. AN AGRICULTURAL HOPPER 
MOVED APPROXIMATELY 1000 FEET. LARGE TREES OR TREE LIMBS WERE 
SNAPPED IN FIVE LOCATIONS WITHIN THE AREA THAT RECEIVED WIND DAMAGE. 
CORN FIELDS WERE FLATTENED. VEGETATION WAS REMOVED FROM A 30 FOOT 
WIDE CIRCULAR AREA OF A FARM FIELD. ALL OF THIS DAMAGE WAS 
DETERMINED TO HAVE BEEN CAUSED BY STRAIGHT LINE WINDS AND EMBEDDED 
MICROBURSTS.

FOR REFERENCE...
A MICROBURST IS A CONVECTIVE DOWNDRAFT WITH AN AFFECTED OUTFLOW AREA
OF LESS THAN 2 1/2 MILES WIDE AND PEAK WINDS LASTING LESS THAN
5 MINUTES. MICROBURSTS MAY INDUCE DANGEROUS HORIZONTAL/VERTICAL
WIND SHEARS...WHICH CAN ADVERSELY AFFECT AIRCRAFT PERFORMANCE AND
CAUSE PROPERTY DAMAGE. STRAIGHT-LINE WINDS ARE GENERALLY ANY WIND
THAT IS NOT ASSOCIATED WITH ROTATION...USED MAINLY TO DIFFERENTIATE
THEM FROM TORNADIC WINDS.

$$