UDC 661.W6.1:661.613:661.677.3(78/79)"1973.08" WEATHER AND CIRCULATION OF AUGUST 1973 Continued Drought in the Northwest-

• Main Author: National Weather Service
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Canada; Pacific; Newfoundland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.395.1272; http://docs.lib.noaa.gov/rescue/mwr/101/mwr-101-11-0833.pdf

The mean circulation at 700 mb during August was highly amplified relative to the normal for this time of year (figs. 1, 2). The wave pattern was considerably simpler than that of July (Wagner 1973); there were four prominent waves at mid-latitudes. A strong circumpolar Low persisted at high latitudes a.nd a girdle of abovenormal heights covered the subtropics. Cold air advection east of strong ridges over central Asia and eastern Canada strengthened baroclinic zones in China and near Newfoundland. Conversion of this available potential energy is evidenced by wind speed maxima and increasing winds immediately east of these areas (fig. 3). The relatively flat flow over the Pacific Ocean during July (Wagner 1973) gave way to an amplified flow pattern