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Official National Weather Service Tornado Report

Official National Weather Service Tornado Report
Here is the full report from the National Weather Service on the Enumclaw area tornado on Sept. 6:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SEATTLE WA
1010 PM PDT MON SEP 7 2009

..BUCKLEY-ENUMCLAW TORNADO ON SEPTEMBER 6 2009...

A THUNDERSTORM THAT FORMED NEAR LAKE TAPPS IN NORTH CENTRAL
PIERCE COUNTY LATE SUNDAY AFTERNOON SEPTEMBER 6TH SPUN UP A
TORNADO THAT CAUSED A PATH OF DESTRUCTION FROM JUST SOUTH OF LAKE TAPPS TO NORTH OF ENUMCLAW.

IT WAS ESTIMATED THAT THE TORNADO MAY HAVE FIRST TOUCHED DOWN AROUND 419 PM NEAR THE INTERSECTION OF VANDEMARK ROAD EAST AND 214TH AVENUE E...JUST SOUTH OF LAKE TAPPS. BARELY ANY DAMAGE WAS NOTED IN THIS AREA.

THE THUNDERSTORM AND TORNADO WERE MOVING ALMOST DUE NORTHEAST AT AN ESTIMATED SPEED OF 36 MILES AN HOUR. THE GREATEST DAMAGE CAUSED BY THE TORNADO OCCURRED SHORTLY AFTER THE INITIAL TOUCHDOWN. AFTER SKIPPING OVER A SMALL VALLEY IT TOUCHED DOWN AGAIN AROUND 420 PM ALONG BUCKLEY-TAPPS HIGHWAY E...WHERE IT DESTROYED A 92 YEAR OLD BARN...BLEW ROOFING OFF AN ADJOINING BARN...DESTROYED A LARGE SILO...BLEW OVER A SMALL TRAVEL TRAILER...AND EITHER SNAPPED LARGE BRANCHES OFF OF NEARBY TREES OR COMPLETELY SNAPPED OFF THE TREE.

DEBRIS WAS STREWN UP TO 240 YARDS DOWNSTREAM ACROSS PASTURES TO THE NORTHEAST OF THE FARM. A COUPLE OF PIECES OF THE ROOFING WERE COMPLETELY WRAPPED AROUND TREES. BASED ON THE DAMAGE...THE TORNADO WINDS WERE ESTIMATED TO BE 100 T0 110 MILES AN HOUR...WHICH CORRESPONDS TO THE HIGH END FOR AN ENHANCED FUJITA SCALE LEVEL 1 TORNADO.

THE ENHANCED FUJITA SCALE RATES THE STRENGTH OF TORNADOES
BASED ON THE RESULTING DAMAGE. EF 0 CORRESPONDS TO THE WEAKEST TORNADOES AND EF 5 IS THE RATING FOR THE STRONGEST MOST DEVASTATING TORNADOES.

THE BUCKLEY-ENUMCLAW TORNADO CONTINUED TO TOUCH DOWN INTERMITTENTLY OVER THE NEXT 15 MINUTES AS IT MOVED NORTHEAST ACROSS SOUTH KING COUNTY. ALONG THE REST OF THE DAMAGE PATH LARGE TREES WITH DIAMETERS BETWEEN 10 AND 21 INCHES WERE SNAPPED OFF 20 T0 30 FEET ABOVE THE GROUND. A FEW BUILDINGS LOST PIECES OF ROOFING. THE TORNADO APPEARED TO CROSS OVER WESTWOOD ELEMENTARY SCHOOL BUT ONLY MINOR TREE LIMB DAMAGE WAS NOTED.

ABOUT 2 MILES PAST THE ELEMENTARY SCHOOL THE TORNADO PASSED RIGHT NEXT TO THE GE AND B NURSERY...WHERE THE SECOND MOST BUILDING DAMAGE WAS NOTED. THE PLASTIC COVERINGS WERE RIPPED OFF OF SEVERAL OF THE GREENHOUSES...ROOFING WAS BLOWN OFF OF SOME OF THE BUILDINGS AND TREE STOCK WAS BLOWN AROUND. RIGHT ACROSS THE ROAD FROM THE NURSERY...SE 400TH STREET...LARGE TREES UP TO A FOOT IN DIAMETER WERE SNAPPED OFF UP TO 35 FEET ABOVE THE GROUND.

MORE INTERMITTENT TREE DAMAGED OCCURRED ALONG THE REST OF THE
PATH...NEAR KING COUNTY FIRE STATION NUMBER 94...AND JUST
NORTHEAST OF BASS LAKE. ONE LARGE TREE AT BASS LAKE WAS MEASURED AT 21 INCHES IN DIAMETER WHERE IT WAS AS SNAPPED OFF. THE END OF THE 9.6 MILE DAMAGE PATH WAS ESTIMATED TO BE ALONG ENUMCLAW-FRANKLIN ROAD SE ABOUT 4 MILES NORTH OF DOWNTOWN ENUMCLAW...WHERE A 10 INCH DIAMETER TREE WAS SNAPPED OFF.

TORNADO DATA...

LENGTH OF DAMAGE PATH...........9.6 MILES
MAXIMUM WIDTH OF DAMAGE PATH....150 YARDS
DURATION......,,,,,,,...........16 MINUTES FROM 419 PM TO 435 PM.
SPEED-DIRECTION OF MOVEMENT.....NORTHEAST AT 36 MILES AN HOUR
ESTIMATED MAXIMUM WINDS.........100 TO 110 MILES AN HOUR ENHANCED
FUJITA SCALE RATING.............HIGH END EF 1.