Oregon Tornadoes:
More Fact Than Fiction
or, from
January/February 2011
Weatherwise:
Oregon’s Twisted History
by
George R. Miller
Meteorologist, NWS, Retired
Presentation:
1.Describes some historic tornado and
severe weather events in Oregon.
2.Categorizes severity using F-scale, NWS
documentation, and author’s estimation.
3.Data accumulated from newspapers,
county historical documents, NWS (Weather
Bureau) publications, personal interviews.
“TORNADOES ARE UNKNOWN.”
ANNUAL METEOROLOGICAL SUMMARY
WITH COMPARATIVE DATA, PORTLAND,
OREGON 1922
“Well developed tornadoes are
unknown.”
Annual Meteorological Summary with
comparative data 1944
Why so few tornadoes prior to
1950?
1. Ban on using the word tornado in forecasts late
1800s to late 1930s.
2. From 1897 to 1916 official tornado documentation
ceased entirely; only most obvious and damaging
thereafter for a period of time.
3. General reluctance to call the event a tornado.
4. Used terms such as: Freak wind, tornado-like wind,
cyclonic-like wind, freak blow, freak twister, weather
freak, freak storm and the classic…
5. “The funnel did not touch the ground!”
6. Even today: “There was no hook echo on the radar.”
Lexington, Oregon, June
14, 1888
•F1 (estimated)
•Path length 15 miles
•Path width 2-4 miles
(estimated)
•Damage $5000
(estimated)
•Several injured; 1-6
killed
Lexington
Long Creek, Oregon
June 3, 1894
•F2 (estimated)
•Path length 10 miles
(estimated)
•Path width ½ mile
•Damage $10,000
(estimated)
•Six injured, 3 killed
•Hail reported 7 ½”
circumference
•Large destruction of
timber
Long Creek
Mapleton, Oregon, June 6,
1948
•Hailstones as large as
hen’s eggs.
•Some probably
baseball size
•Chickens killed
•Car roofs dented
•Hailstones caused
water to splash up 34’ high Siletz river
•Area reported
numerous
thunderstorms
Mapleton
Near Aurora, north of
Salem
March 22, 1967
F0 (estimated)
Path length 2.5 miles
Path width 20 yards
(both estimated)
Damage $2000 to
nursery
Injuries none
Deaths 1 (author’s
assessment)
Not included in any
WB (NWS ) documents
Portland
Willamette
River
Nursery
Aurora
I-5
Wallowa County, north of
Enterprise, Oregon, June
11, 1968
•F2
•Path length 8-10
miles
•Path width ½ to 2
miles
•Damage estimated
$5 to $50 million in
downed timber
•1800 acres of prime
timber destroyed
Enterprise
Vicinity Newberg, Oregon,
December 8, 1993
•Path width 300+ ft
•Damage $600,000
•F2
•Path length 6 miles
•(estimated)
•Possible microburst
to start
•No injuries, no
deaths, but six veal
calves killed
•Marion, Yamhill and
Washington
Newberg
Aumsville
December 14, 2010
EF2
Length 5 miles
Width 150 yards
No injuries
No deaths
Winds 110-120
Fifty structures damaged
Two semi-trailers
overturned
Aumsville
20
18
Oregon Tornadoes
1876-2010
Total: 147
West 78
East 69
16
14
12
10
West Side
East Side
8
6
4
2
0
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Total
Does Oregon Have Its Own “Tornado Alley?”
After passage of cold
upper level trough,
Surface winds often still
southerly while,
850mb and above,
winds have shifted to west
to southwesterly.
Enough wind shear?