 | This article is missing information about systems from 1949 to 1995. (June 2019) |
Tropical storms are tropical cyclones with 1-minute sustained winds between 34–63 knots (39–72 mph; 63–117 km/h). Tropical cyclones that attain such winds and make landfall while maintaining that intensity are capable of causing minor to moderate damage to human lives and infrastructure. Since 1949, at least 490 systems have peaked at tropical storm intensity in the Eastern Pacific basin, which is denoted as the part of the Pacific Ocean north of the equator and east of the International Date Line. This list does not include storms that also attained Category 1, 2, 3, 4, or 5 status on the Saffir–Simpson scale.
There are a plethora of factors that influence tropical cyclogenesis, the formation of tropical cyclones, in the Northeastern Pacific. The North Pacific High and Aleutian Low which occur from December to April, produce strong upper-level winds which prevent the formation of tropical cyclones. During the summer and early autumn months, sea surface temperatures are generally warm enough to support tropical cyclone development in the Northeast Pacific, and perhaps even rapid intensification. Additionally, El Niño events cause more powerful hurricanes to form by generating weaker wind shear and higher sea surface temperatures, while La Niña events reduce the number of such hurricanes by doing the opposite.