The formation of One-E on April 25 marked the earliest start to a Pacific hurricane season on record. However, seasonal activity as a whole was generally below average. The season featured 16 named storms, in line with the 1981–2010 long-term average of 15. It featured just four hurricanes, or half the average. Three of those hurricanes intensified into major hurricanes,[nb 2] which compares to the average of four. A few storms produced substantial impact to land in 2020. In May, Tropical Storm Amanda caused widespread damage and killed numerous people in El Salvador, Guatemala, and Honduras.[3] In August, the remnants of Tropical Storm Fausto sparked devastating wildfires across Northern California,[4] while Genevieve produced hurricane-force winds and caused additional fatalities in the Baja California peninsula.[5] Lesser but still deadly effects were produced there by Tropical Storm Hernan as well.[6] A month prior, Hurricane Douglas passed very close to Oahu, though it caused only minor impact.[7]
This timeline documents tropical cyclone formations, strengthening, weakening, landfalls, extratropical transitions, and dissipations during the season. It includes information that was not released throughout the season, meaning that data from post-storm reviews by the National Hurricane Center, such as a storm that was not initially warned upon, has been included.
By convention, meteorologists use one time zone when issuing forecasts and making observations: Coordinated Universal Time (UTC), and also use the 24-hour clock (where 00:00 = midnight UTC).[8] Tropical cyclone advisories in the Eastern North Pacific basin use both UTC and the nautical time zone where the center of the tropical cyclone is currently located. Time zones utilized (east to west) are: Central, Mountain, Pacific and Hawaii. In this timeline, all information is listed by UTC first, with the respective regional time zone included in parentheses. Additionally, figures for maximum sustained winds and position estimates are rounded to the nearest 5 units (knots, miles, or kilometers), following National Hurricane Center practice. Direct wind observations are rounded to the nearest whole number. Atmospheric pressures are listed to the nearest millibar and nearest hundredth of an inch of mercury.
18:00 UTC (11:00 a.m. PDT) – Tropical Depression Six-E dissipates about 610 mi (980 km) west-southwest of the southern tip of the Baja California peninsula.[13]
^The tropical cyclone designation is a universal term referring to organized collections of thunderstorms located near a well-defined area of low pressure. Tropical storms, hurricanes, and major hurricanes are all classifications of a tropical cyclone based on their maximum sustained winds within the National Hurricane Center's jurisdiction.[1]
^Hurricanes reaching Category 3 (111 mph (179 km/h)) and higher on the 5-level Saffir–Simpson scale are considered major hurricanes.[2]
^In a post-season review of Tropical Depression Seven-E, the National Hurricane Center determined that the depression briefly reached tropical storm intensity. Since the depression was not considered a tropical storm while it was initially active, it was not named.[14]
