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On the relationship between winter storms, strong winds, and the associated pressure field along a rugged western coast

Two successive years of wind speed and direction data, from
January 1973 through December 1974, have been measured and
recorded at Yaquina Head, 6 km north of Newport, Oregon. Analysis
of the data permitted 65 cases of strong wind to be isolated and
separated into four distinct wind speed categories. With the aid of
surface charts, upper air sounding, and sea level pressures from
several stations, numerous meteorological events, occurring concurrently
with peak winds at Yaquina Head, have been evaluated for a
significant contribution to the local wind.
Cyclone centers associated with strong coastal wind have been
plotted and analyzed with regard to location, speed and direction of
motion, sea surface pressure, and pressure change during periods
of strong winds. The result of this analysis indicates that many cases
of strong coastal wind measured at Yaquina Head are associated with
cyclones located southwest of Vancouver Island, British Columbia.
The pressure change experienced by these cyclones is related to the
strength of the observed wind at Yaquina Head. Likewise, the locations
of these pressure centers are related to the duration of strong
wind measured at Yaquina Head. The direction of motion of the
cyclones and the value of the sea surface pressure at the center of
the cyclones seem unrelated to local wind speed.
Frontal zones associated with cases of strong wind have been
evaluated with regard to type, speed, and direction of motion prior
to strong surface winds. No relationship was found between these
factors and the strength of the wind.
The direction of the wind versus the speed of the wind was
reviewed and the results were separated into several classes. The
result of this classification indicated that in 73 percent of the cases
the measured peak wind occurred prior to an abrupt veering of the
wind. Only 21 percent of the cases lacked this wind shift.
The local pressure field was examined for pressure differences
which might result in a strong coastal wind flow. Station
pressures from three locations were used as well as barograms
from Newport, Oregon, in describing the pressure field. No correlation
between these pressures differences and the strength of the
local wind could be found. Finally, the north-south component of
the geostrophic wind was calculated and compared with speed of the
measured wind. No consistent agreement could be established
between the measured surface wind speed and the calculated north-
south component of the geostrophic wind.
The lack of data west of Yaquina Head and Oregon Coast
continue to present a problem for those who consider coastal winds. / Graduation date: 1977

Identiferoai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/28951
Date21 September 1976
CreatorsMcDonough, Thomas Andrew
ContributorsDecker, Fred W.
Source SetsOregon State University
Languageen_US
Detected LanguageEnglish
TypeThesis/Dissertation

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