Hurricane Olaf intensified into a major Category 3 hurricane on Monday at 11 am EDT in the waters about 1350 miles east-southeast of Hawaii, becoming the tenth hurricane and eighth major hurricane of this very busy Eastern Pacific hurricane season. Olaf became a major hurricane unusually far to the south--at 9.9°N latitude, making it the most southerly major hurricane ever observed in the Eastern Pacific since reliable records began in 1971.

This year now ties with 2014 and 1992 for the most number of major Eastern Pacific major hurricanes (east of 140°W) in a season--eight. An average Eastern Pacific hurricane season sees 15 named storms, 8 hurricanes, and 3 intense hurricanes, and we have already had 15 named storms, 10 hurricanes, and 8 intense hurricanes so far in 2015.

This is the second consecutive year with unusually heavy activity in the Eastern Pacific--in 2014, the basin had 20 named storms, 13 hurricanes, and 8 intense hurricanes, making it the busiest season since 1992, which set records for total number of named storms (24), hurricanes (14), and intense hurricanes (8). It has also been a hyperactive year for hurricanes in the Central Pacific, between 140°W and 180°W. So far in 2015, eight named storms have formed in the Central Pacific, setting a new record for tropical cyclone activity in that basin. According to wunderblogger Dr. Phil Klotzbach, prior to 2015, the previous record for named storms in the North Central Pacific for an entire season was four, set in 1982. This year's record activity in both the Eastern Pacific and Central Pacific has been due to unusually low wind shear and record-warm ocean temperatures caused by the strong El Niño event underway.

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=3159