312
ABUS34 KSPI 202046
PNSSPI
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE LINCOLN IL
345 PM CDT MON AUG 20 2001

...STORMS FROM AUGUST 18TH...

...RESULTS OF STORM SURVEY FROM DEWITT AND PIATT COUNTIES...

A SEVERE WEATHER EVENT OCCURRED IN CENTRAL ILLINOIS ON
SATURDAY...AUGUST 18.  NWS EMPLOYEES CONDUCTED A DAMAGE SURVEY ON
SUNDAY OF A PORTION OF THE DAMAGE IN THE DEWITT AND PIATT COUNTY
AREAS.  HERE ARE THE RESULTS.

AN AREA OF STRAIGHT LINE...DAMAGING DOWNBURST WINDS APPEARS TO HAVE
MOVED ACROSS THE CENTRAL PART OF DEWITT COUNTY. THE AREA OF WIND
DAMAGE BEGAN ABOUT 2.25 MILES NORTH OF CLINTON...BETWEEN CLINTON AND
WAPELLA. THE DAMAGE THEN EXTENDED EAST ACROSS CLINTON LAKE TO THE
TOWN OF DEWITT. THE DAMAGE RANGED FROM 2 TO 3 MILES IN WIDTH. THE
EXTENT OF THE DAMAGE INCLUDED...SIDING AND A CEMENT WALL BLOWN OVER
AT A CONSTRUCTION SIGHT NORTH OF CLINTON...CAMPERS BLOWN OVER AT THE
CLINTON LAKE STATE PARK...AND THE SPORADIC TREES OR TREE LIMBS BLOWN
DOWN...PLUS SOME DAMAGE TO CROPS DUE TO THE WIND AND LARGE HAIL.
THE ESTIMATE ON THE SPEED OF THE WINDS WAS AROUND 70 MPH.
APPROXIMATE OCCURRENCE TIME WAS 200 PM TO 208 PM.

FOR THE TOWN OF DEWITT...IN ADDITION TO THE STRAIGHT LINE...DAMAGING
DOWNBURST WINDS THAT AFFECTED THE TOWN...IT APPEARS THAT A SMALL
TORNADO DEVELOPED AND BRIEFLY TOUCHED DOWN ON THE WEST SIDE OF
TOWN.  FROM DOPPLER RADAR DATA...EYE WITNESSES...AND DAMAGE
MAPPING...THE SMALL TORNADO APPEARS TO HAVE TOUCHED DOWN ABOUT 1/3
MILE NORTHWEST OF TOWN...MOVED 1/3 MILE SOUTHEAST INTO THE WEST
CENTRAL PART OF TOWN...AND THEN LIFTED IN THE CENTER OF TOWN.  THE
PATH LENGTH WAS ABOUT 1/3 MILE AND THE WIDTH WAS ABOUT 100 YARDS.
THE ESTIMATED WIND SPEEDS ON THE TORNADO WAS AROUND 70 MPH...RATED
F0 ON THE FUJITA SCALE.  DAMAGE ON THE WEST SIDE OF TOWN INCLUDED A
CHIMNEY BLOWN OFF THE CHURCH WITH WINDOWS BLOWN OUT AND SOME MINOR
ROOF DAMAGE.  TWO HOMES HAD ROOF AND SHINGLE DAMAGE AND ONE GARAGE
WAS BLOWN DOWN...WITH NUMEROUS LARGE TREES RIPPED UP AND BLOWN OVER.
ONE HOUSE HAD HAIL DAMAGE TO SIDING. APPROXIMATE TIME OF OCCURRENCE
OF THE TORNADO IS FROM 205 PM TO 208 PM.

NOTE THAT THIS TORNADO APPEARS TO HAVE DEVELOPED WITHIN THE LARGER
AREA OF STRAIGHTLINE WINDS. THE STRAIGHTLINE WINDS CAUSED MANY TREES
AND TREE LIMBS TO BE BLOWN DOWN THROUGHOUT THE REMAINDER OF THE TOWN
OF DEWITT.

NEXT...THE STRAIGHT LINE...DOWNBURST WINDS BEGAN AGAIN FROM ABOUT 2
MILES SOUTH OF DEWITT...STRETCHING SOUTHEAST TO ABOUT 2.5 MILES
NORTH OF WELDON. THE WIDTH ON THIS AREA WAS ABOUT 2 MILES WIDE.
DAMAGE IN THIS AREA WAS AGAIN THE SPORADIC TREE OR TREE LIMB BLOWN
DOWN...PLUS SOME SIDING OFF A HOME...CORN BLOWN DOWN...AND A GRAIN
BIN PICKED UP AND CARRIED ABOUT 150 FEET (50 YARDS).  APPROXIMATE
TIME OF OCCURRENCE FROM 208 PM TO 213 PM.

FROM RADAR...THE STORM APPEARED TO THEN WEAKEN AND MOVE INTO PIATT
COUNTY. SOME STORM STRENGTHENING THEN OCCURRED AND MORE WIND DAMAGE
WAS PRODUCED SOUTH AND SOUTHEAST OF FARMER CITY IN PIATT COUNTY.
THIS DAMAGE WAS AGAIN SPORADIC IN NATURE...CENTERED ON A LINE FROM
2.5 MILE SOUTH OF FARMER CITY TO 3.5 SOUTHWEST OF MANSFIELD...AND
ABOUT 2-3 MIILES WIDE.  DAMAGE CONSISTED OF SEVERAL TREES BLOWN
DOWN...A BLOWN IN DOOR ON A FARM MACHINERY SHED...AND CORN BLOWN
DOWN. APPROXIMATE TIME OF OCCURRENCE FROM 223 PM TO 235 PM.

...AN ADDITIONAL TORNADO REPORT...

IN ADDITION...CHAMPAIGN COUNTY ESDA REPORTED AT WEATHER SPOTTERS AT
312 PM SAW A BRIEF TOUCHDOWN OF A SMALL TORNADO BETWEEN ST. JOSEPH
AND OGDEN.  NO DAMAGE WAS REPORTED AT THIS TIME AS THE TOUCHDOWN WAS
IN AN OPEN FIELD.

...SUMMARY ON TORNADOES...

AT THIS TIME...TWO (2) TORNADOES HAVE BEEN CONFIRMED FROM THE
AUGUST 18 EVENT. AS FURTHER INFORMATION COMES IN AND LATER REPORTS
ARE RECEIVED...THE OFFICIAL STORM DATA RECORDS WILL BE UPDATED AS
NEEDED.

ERNEST H. GOETSCH - METEOROLOGIST IN CHARGE
DAN KELLY - METEOROLOGIST