THE WEATHER AND CIRCULATION OF OCTOBER 1966 Cool Weather With Strong Polar Blocking

• Main Author: L. P. Stark
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Canada; Greenland; Alaska
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.395.2508; http://docs.lib.noaa.gov/rescue/mwr/095/mwr-095-01-0049.pdf

Strong blocking in very high latitudes partially controlled the mid-tropospheric circulation and surface weather over most of the United States and Canada during October 1966. Some measure of the strength of the blocking may be seen in the polar index as determined from the flow in the western portion of the Northern Hemisphere from 55 ' N. to 75 " N. At the 700-mb. level polar westerlies were 1.8 meters per second below normal and at the surface polar easterlies mere 2.2 m.p.s. above normal. The blocking appeared strong in consideration of the mean 700-mb. flow for October (fig. 1) and the 700-mb. height anomaly flow (fig. 2). The former chart shows a ridge over Greenland and another north of Alaska. But the height anomaly chart defines the blocking much better: 700-mb. heights mere as much as