Timeline of the 2024 Pacific hurricane season

The 2024 Pacific hurricane season is the current tropical cyclone season in the Pacific Ocean east of the International Date Line (IDL) in the Northern Hemisphere. It officially began on May 15 in the eastern Pacific (east of 140°W), and on June 1 in the central Pacific (from the IDL east to 140°W); it will end in both on November 30. These dates, adopted by convention, historically describe the period in each year when most tropical cyclogenesis occurs in these regions of the Pacific. The season's first system, Tropical Storm Aletta, developed on July 4.

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). 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.

May

 * No tropical cyclones form in the Eastern Pacific basin during the month of May.

May 15
 * The Eastern Pacific hurricane season officially begins.

June
June 1
 * No tropical cyclones form in the Eastern or Central Pacific basins during the month of June.
 * The Central Pacific hurricane season officially begins.

July
July 4
 * 15:00 UTC (9:00 a.m. CST) at 17°N, -105.9°W – Tropical Depression One-E forms about 175 mi (280 km) southwest of Manzanillo, Mexico.
 * 21:00 UTC (2:00 p.m. MST) at 17.9°N, -107°W – Tropical Depression One-E strengthens into Tropical Storm Aletta and simultaneously reaches peak intensity with maximum sustained winds of 35 kn and a minimum central pressure of 1005 mbar, about 190 mi (310 km) west-southwest of Manzanillo.

July 5
 * 09:00 UTC (2:00 a.m. MST) at 18.7°N, -108.7°W – Tropical Storm Aletta weakens to a tropical depression about 300 mi (485 km) south-southeast of the southern tip of Baja California.

July 6
 * 03:00 UTC (8:00 p.m. MST July 5) at 18.4°N, -111.6°W – Tropical Depression Aletta degenerates to a remnant low about 300 mi (530 km) south-southwest of the southern tip of Baja California.