From: mfoster@alliant.backbone.uoknor.edu (Marc Foster)
Subject: Damage report from Purcell/Wayne OK tornado of 2 Sept 1992
Summary: Not quite Andrew caliber, but significant nonetheless  
Originator: usenet@essex.ecn.uoknor.edu
Date: Thu, 10 Sep 1992 22:38:02 GMT
Distribution: na
Organization: University of Oklahoma, Norman, OK
Keywords: Out of Season!!! 

     The following are the results of a damage survey conducted jointly by 
representatives of the National Weather Service (NWS), the National Severe
Storms Laboratory (NSSL), and the University of Oklahoma School of Meteorology
(OU).  The survey was performed on 3 September 1992, and focused on reported
damage from one or more tornadoes that occurred in southern McClain County
on the evening of 2 September 1992.  The survey team consisted of Greg Stumpf,
NSSL; Marc Foster, OU; and Mike Branick, NWS.

     We wish to thank the many individuals who were in or near the damage path
and provided us with valuable information.  We also wish to thank the McClain
County Sheriff's Office for their valuable input regarding the locations of the
most serious damage.

                                  * * * *

     On the evening of Wednesday, 2 September, a strong tornado touched down
southwest of Purcell and left a nearly continuous 8- to 9-mile path of damage
as it moved to the east-southest across southern McClain County.  The most
intense damage occurred from near highway 77 south of Purcell to a rural area
northeast of Wayne, where damage was rated F2 on the Fujita scale of wind
damage intensity.  Based on this assessment of wind damage, maximum winds were
estimated to be between 115 and 130 mph in the areas of maximum damage.  
Although most of the damage occurred to trees and crops, at least seven homes,
eight power poles, and several outbuildings were either damaged or destoyed.
As of this writing, only one injury is attributable directly to the tornado.

     Initial touchdown occurred near the southwestern end of Purcell Lake, or
about 2.5 miles SW of downtown Purcell.  From this point, the tornado left an
intermittent path of minor /F0/ damage to trees for about a mile until it 
crossed Highway 74 about 1/2 mile SW of the intersection of Highway 74 and 
I-35.

     Just east of Highway 74, the tornado intensified and began a continuous
path of damage that traversed about 6 miles and averaged 300 to 500 yards in 
width.  Numerous large trees were snapped off or uprooted, and at least three
homes suffered roof and other minor structural damage between Highway 74 and 
I-35 about 3 miles south of downtown Purcell.  Residents in one home heard a 
loud roar and went to their bathroom; their home suffered minor roof damage
(shingles lost), but no major structural damage.  Numerous trees and large
branches were downed  in the yard just N of the home.  All were blown to the
NE, but trees of similar size about 100 yards further N were blown to the SE.
This convergent pattern was used to identify the center of the tornado path as
having passed within a few hundred feet to the N of the house.  Had it been 100
yards further S, the large trees in the yard would likely have landed on the 
house and inflicted more serious damage.  Patterns in low-growing vegetation
just W of I-35 indicate convergenge of strong winds along an axis that crossed
the interstate very close to mile marker 90.  Over this area, maximum damage 
was rated F1.

     After crossing I-35, the tornado destoyed a large sheet metal barn just
E of the interstate.  Thereafter, it intensified as it approached Highway 77. 
A home on Highway 77 suffered signifigant damage, losing at least 80 percent of
its hip-style roof and a small part of a brick outer wall.  A nearby storage/
work shed was destroyed, and several large trees were uprooted of heavily
damaged.  A riding lawn mower and a large flatbed trailer were thrown about 75
yards from a point just north of the house.  Patterns in the debris and grass 
in a field just N and E of the house indicate the center of the damage path 
passed within 100 yards to the N and E of the house.  Damage in the area was 
rated F2.  A pickup truck was overturned on Highway 77 as the tornado crossed,
and the lone occupant was injured when thrown from the vehicle.

     Continuing ESE, the tornado produced more tree damage and damage another
home about a mile ESE from the previos home.  Numerous trees were uprooted or
heavily damaged, and at least 8 power poles that supported 115 kV high-tension
lines were downed along a 2-miles swath extending to about 1.5 to 2 miles N of
Wayne.  Although the damage path closely paralleled the power lines, the
damage pattern suggests that the center of the path crossed the power lines at
two locations.  This conclusion is based on the fact that three adjacent poles
were downed, followed by a nearly 1-mile stretch with undamaged poles, and then
another stretch of 5 adjacent poles down.  An entire 100 yard string of 
irrigation equipment was flipped over in a field 2 miles N of Wayne, very close
to where the 5 poles were downed.  Maximum damage, based on the downed power
poles, was rated low-F2 over this stretch, although most of the damage was in
the F1 category.

     Damage continued as the tornado turned a little more to the E after
passing due N of Wayne.  Damage remained limited to trees and crops until
reaching two rural homes about 2 miles NNE of Wayne.  One home suffered low-F1
damage, with several large trees downed all around the surrounding lot, while
the second home suffered more significant - but still F1 damage.  The second 
home suffered structural damage when winds apparently entered through a door 
in the SW part of the house.  The winds forced an outward shift of several 
inches to a north wall in the NE part part of the house, and blew a large
picture window outward.  A considerable amount of blown grass and hay was
plastered to the W and N walls, both inside and outside, around the NE part of
the house.  Although damage to the home was rated F1, damage to nearby trees
and peripheral structures prompted an F2 rating near the center of the tornado
track in this area.  Two large outbuildings were destroyed , and a full 250-
gallon propane tank estimated at 1 ton was blown/rolled about 1/4 mile before
coming to a stop in a nearby peanut field.  At least 4 large trees, with trunks
up to 3 feet in diameter and roots over 6 feet in diameter, were uprooted. A 
line of trees suffered considerable F2 damage about 100 yards N of the second
home.  Residents near this home saw an area of rotation approaching, and headed 
to shelter upon hearing a loud roar.  None were injured.

     After passing into the peanut field, the tornado entered its dissipating 
stage about 2 miles NE of Wayne.  Numerous sections of sheet metal and other 
debris were carried into the field, but further damage was limited to broken 
limbs for about another mile.  The last evidence of damage was to tree limbs 
about 3 miles ENE of Wayne. 

     Local eyewitnesses and storm spotters report that the tornado itself was
wrapped in heavy precipitation during most of its lifetime, and was not clearly
visible until it moved to NE of Wayne and entered its dissipating stage.
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