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Tuesday, April 27th Wind Storm
East Wenatchee
Tornado - May 19th, 2004
At around 4pm PDT on May 19th a strong thunderstorm produced a short lived
tornado over East Wenatchee, Washington. The following pictures were taken and
submitted by the Krausman family of East Wenatchee. The first photo shows the
tornado as evidenced by the debris or dust and soil present near the surface.
This likely was formed by a process similar to dust devils and intensified by
the updraft of the thunderstorm. The second photo shows hail that was produced
by this thunderstorm. Estimates from the photo indicate the hail is approximately
3/4 inch.
Post analysis of the event suggests this was an example of a landspout,
or a non-supercell tornado in a weak wind shear environment. They are not an
unusual occurrence; one was sited near Moses Lake just last spring. Essentially,
a landspout forms when a broad, weak area of rotation in the low levels of the
atmosphere is caught up in the updraft of a developing cumulus cloud or thunderstorm.
The effect is similar to that of a figure-skater pulling in her arms to spin
faster. As the area of rotation is stretched and constricts, it spins faster
until condensation occurs and the funnel becomes visible. In this case, the
landspout was in contact with the ground as seen by the debris cloud. Thus,
by definition, it was a tornado.
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