The 2023 Pacific hurricane season was a fairly active Pacific hurricane season. In the eastern Pacific basin (east of 140°W), 17 named storms formed; 10 of those became hurricanes, and 8 further intensified into major hurricanes (category 3 or higher on the 5-level Saffir–Simpson wind speed scale). In the central Pacific basin (between 140°W and the International Date Line), no tropical cyclones formed (for the fourth consecutive season), though four entered into the basin from the east. The season officially began on May 15, 2023, in the eastern Pacific, and on June 1 in the central Pacific; it ended 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 Adrian, developed on June 27, and its last, Tropical Storm Ramon, dissipated on November 26.
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.
The time stamp for each event is first stated using Coordinated Universal Time (UTC), the 24-hour clock where 00:00 = midnight UTC. The NHC uses both UTC and the time zone where the center of the tropical cyclone is currently located. The time zones utilized (east to west) are: Central, Mountain, Pacific and Hawaii. In this timeline, the respective area time is included in parentheses. Additionally, figures for maximum sustained winds and position estimates are rounded to the nearest 5 units (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. __TOC__
Timeline
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 The Central Pacific hurricane season officially begins.
June 27 12:00 UTC (6:00 a.m. MDT) at A tropical depression forms from a tropical wave about south of Manzanillo, Colima. 18:00 UTC (12:00 p.m. MDT) at The tropical depression strengthens into Tropical Storm Adrian about south of Manzanillo.
June 28 12:00 UTC (6:00 a.m. MDT) at Tropical Storm Adrian strengthens into a Category 1 hurricane about southwest of Manzanillo.
June 29
06:00 UTC (1:00 a.m. CDT) at Tropical Depression TwoE forms from a tropical wave about southeast of Acapulco, Guerrero. 12:00 UTC (7:00 a.m. CDT) at Tropical Depression TwoE strengthens into Tropical Storm Beatriz about south-southeast of Acapulco.
June 30 06:00 UTC (12:00 a.m. MDT) at Hurricane Adrian intensifies to Category 2 strength about west-southwest of Manzanillo. 12:00 UTC (6:00 a.m. MDT) at Hurricane Adrian reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of , about west-southwest of Manzanillo. 12:00 UTC (7:00 a.m. CDT) at Tropical Storm Beatriz strengthens into a Category 1 hurricane about southeast of Manzanillo, Colima. 18:00 UTC (4:00 p.m. CDT) at Hurricane Beatriz reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of , about southeast of Manzanillo.
July
July 1 00:00 UTC (6:00 p.m. MDT, June 30) at Hurricane Adrian weakens to Category 1 strength about west-southwest of Manzanillo. 06:00 UTC (1:00 a.m. CDT) at Hurricane Beatriz weakens into a tropical storm while making landfall west of Manzanillo International Airport with sustained winds of and a central pressure of , then quickly dissipates. 12:00 UTC (6:00 a.m. MDT) at Hurricane Adrian weakens into a tropical storm about west of Manzanillo.
July 2 12:00 UTC (5:00 a.m. PDT) at Tropical Storm Adrian degenerates into a remnant low about west-northwest of Manzanillo, and subsequently dissipates.
July 11 06:00 UTC (12:00 a.m. MDT) at Tropical Storm Calvin forms from a disturbance in the eastern Pacific monsoon trough about south-southwest of Zihuatanejo, Guerrero.
July 13 12:00 UTC (5:00 a.m. PDT) at Tropical Storm Calvin strengthens into a Category 1 hurricane about southwest of the southern tip of the Baja California peninsula.
July 14
00:00 UTC (5:00 p.m. PDT, July 13) at Hurricane Calvin intensifies to Category 2 strength about southwest of the southern tip of the Baja California peninsula. 12:00 UTC (5:00 a.m. PDT) at Hurricane Calvin intensifies to Category 3 strength about southwest of the southern tip of the Baja California peninsula, making it the first major hurricane of the season. 18:00 UTC (11:00 a.m. PDT) at Hurricane Calvin reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of , about west-southwest of the southern tip of the Baja California Peninsula.
July 15 06:00 UTC (11:00 p.m. PDT, July 14) at Hurricane Calvin weakens to Category 2 strength about west-southwest of the southern tip of the Baja California peninsula.
July 16 00:00 UTC (5:00 p.m. PDT, July 15) at Hurricane Calvin weakens to Category 1 strength about southeast of Ka Lae, the southernmost point of the Big Island of Hawaii. 18:00 UTC (11:00 a.m. PDT) at Hurricane Calvin weakens into a tropical storm about southeast of Ka Lae.
July 17 12:00 UTC (2:00 a.m. HST) at Tropical Storm Calvin enters the Central Pacific basin about southeast of Ka Lae.
July 19 18:00 UTC (8:00 a.m. HST) at Tropical Storm Calvin degenerates into a remnant low about southwest of Ka Lae, and later dissipates.
July 20 12:00 UTC (5:00 a.m. PDT) at Tropical Depression FourE forms.
July 21 00:00 UTC (5:00 p.m. PDT, July 20) at Tropical Depression FourE reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of .
July 22 00:00 UTC (5:00 p.m. PDT, July 21) at Tropical Depression FourE degenerates into a remnant low.
July 31 18:00 UTC (1:00 p.m. CDT) at Tropical Depression FiveE forms from a tropical wave about south of Manzanillo, Colima.
August
August 1 06:00 UTC (12:00 a.m. MDT) at Tropical Depression FiveE strengthens into Tropical Storm Dora about south-southwest of Manzanillo.
August 2 00:00 UTC (6:00 p.m. MDT, August 1) at Tropical Storm Dora strengthens into a Category 1 hurricane about west-southwest of Manzanillo. 12:00 UTC (6:00 a.m. MDT) at Hurricane Dora intensifies to Category 2 strength about south-southwest of the southern tip of the Baja California peninsula.
August 3 00:00 UTC (5:00 p.m. PDT, August 2) at Hurricane Dora intensifies to Category 3 strength about southwest of the southern tip of the Baja California peninsula, making it the second major hurricane of the season. 06:00 UTC (11:00 p.m. PDT, August 2) at Hurricane Dora intensifies to Category 4 strength about southwest of the southern tip of the Baja California peninsula. 12:00 UTC (5:00 a.m. PDT) at Hurricane Dora weakens to Category 3 strength about southwest of the southern tip of the Baja California peninsula.
August 4 00:00 UTC (5:00 p.m. PDT, August 3) at Hurricane Dora re-intensifies to Category 4 strength about southwest of the southern tip of the Baja California peninsula. 12:00 UTC (8:00 a.m. PDT) at Hurricane Dora weakens to Category 3 strength about west-southwest of the southern tip of the Baja California peninsula.
August 5 00:00 UTC (5:00 p.m. PDT, August 4) at Hurricane Dora weakens to Category 2 strength about west-southwest of the southern tip of the Baja California peninsula. 12:00 UTC (6:00 a.m. MDT) at Tropical Depression SixE forms from a tropical wave. 18:00 UTC (11:00 a.m. PDT) at Hurricane Dora rapidly re-intensifies to Category 4 strength about west-southwest of the southern tip of the Baja California peninsula. 18:00 UTC (12:00 p.m. MDT) at Tropical Depression SixE strengthens into Tropical Storm Eugene.
August 6
00:00 UTC (5:00 p.m. PDT, August 5) at Hurricane Dora reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of , about west-southwest of the southern tip of the Baja California peninsula. 12:00 UTC (6:00 a.m. MDT) at Tropical Storm Eugene reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of . ~15:00 UTC (5:00 a.m. HST) at Hurricane Dora enters the Central Pacific basin about east-southeast of Hawaii.
August 7 12:00 UTC (5:00 a.m. PDT) at Tropical Storm Eugene degenerates into a remnant low.
August 10 12:00 UTC (2:00 a.m. HST) at Hurricane Dora weakens to Category 3 strength south of Johnston Atoll.
August 11 18:00 UTC (8:00 a.m. HST) at Hurricane Dora weakens to Category 2 strength.
August 12 00:00 UTC (09:00 JST) at Hurricane Dora briefly re-intensifies to Category 3 strength very near the International Date Line; upon crossing Date Line, Dora exits the Central Pacific basin and is redesignated as a typhoon. 12:00 UTC (6:00 a.m. MDT) at Tropical Depression SevenE forms from a tropical wave.
August 13 00:00 UTC (6:00 p.m. MDT, August 12) at Tropical Depression SevenE strengthens into Tropical Storm Fernanda. 18:00 UTC (11:00 a.m. PDT) at Tropical Storm Fernanda strengthens into a Category 1 hurricane.
August 14 00:00 UTC (5:00 p.m. PDT, August 13) at Hurricane Fernanda intensifies to Category 2 strength. 00:00 UTC (5:00 p.m. PDT, August 13) at Tropical Depression EightE forms. 06:00 UTC (11:00 p.m. PDT, August 13) at Hurricane Fernanda intensifies to Category 3 strength, making it the third major hurricane of the season. 06:00 UTC (11:00 p.m. PDT, August 13) at Tropical Depression EightE strengthens into Tropical Storm Greg, then later enters the Central Pacific basin. 12:00 UTC (5:00 a.m. PDT) at Hurricane Fernanda intensifies to Category 4 strength; it simultaneously reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of .
August 15 00:00 UTC (5:00 p.m. PDT, August 14) at Hurricane Fernanda weakens to Category 3 strength. 06:00 UTC (8:00 p.m. HST, August 14) at Tropical Storm Greg reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of , southeast of Hilo, Hawaii. 12:00 UTC (5:00 a.m. PDT) at Hurricane Fernanda weakens to Category 2 strength.
August 16 06:00 UTC (11:00 p.m. PDT, August 15) at Hurricane Fernanda weakens to Category 1 strength. 06:00 UTC (1:00 a.m. CDT) at A tropical depression forms from a tropical wave about south of Acapulco, Guerrero. 12:00 UTC (5:00 a.m. PDT) at Hurricane Fernanda weakens into a tropical storm. 12:00 UTC (7:00 a.m. CDT) at The tropical depression strengthens into Tropical Storm Hilary about southwest of Acapulco.
August 17 06:00 UTC (11:00 p.m. PDT, August 16) at Tropical Storm Fernanda degenerates into a remnant low, and subsequently dissipates. 12:00 UTC (6:00 a.m. MDT) at Tropical Storm Hilary strengthens into a Category 1 hurricane about southwest of Manzanillo, Colima. 18:00 UTC (12:00 p.m. MDT) at Hurricane Hilary intensifies to Category 2 strength about southwest of Manzanillo. 18:00 UTC (8:00 a.m. HST) at Tropical Storm Greg weakens into a tropical depression south of the island of Hawaii, and later degenerates into a remnant low.
August 18
00:00 UTC (6:00 p.m. MDT, August 17) at Hurricane Hilary intensifies to Category 3 strength about west-southwest of Manzanillo, making it the fourth major hurricane of the season. 06:00 UTC (12:00 a.m. MDT) at Hurricane Hilary intensifies to Category 4 strength about west-southwest of Manzanillo; it simultaneously reaches its peak intensity, with maximum sustained winds of and a minimum central pressure of . 18:00 UTC (12:00 p.m. MDT) at Hurricane Hilary weakens to Category 3 strength about west of Manzanillo.
August 19