The 2011 Pacific hurricane season consisted of the events that occurred in the annual cycle of tropical cyclone formation over the Pacific Ocean north of the equator and east of the International Date Line. The official bounds of each Pacific hurricane season are dates that conventionally delineate the period each year during which tropical cyclones tend to form in the basin according to the National Hurricane Center (NHC), beginning on May 15 in the Eastern Pacific proper (east of 140°W) and June 1 in the Central Pacific (140°W to the International Date Line), and ending on November 30 in both areas. However, tropical cyclogenesis is possible at any time of year. The season generated eleven tropical storms, which is below the 1991–2020 average of fifteen. However, all but one became hurricanes and six further strengthened into major hurricanes, eclipsing the 1991–2020 averages of eight hurricanes and four major hurricanes. There were also two tropical depressions that remained below tropical storm status. The first system, Hurricane Adrian, formed on June 7; the final, Hurricane Kenneth, was the latest in a calendar year to exist east of 140°W since 1983, dissipating on November 25.

Several tropical cyclones impacted land during the 2011 season. The deadliest was Tropical Depression , which was part of a large area of torrential rains over Central America in mid-October. Widespread and destructive flooding and mudslides occurred in southeastern Mexico and Guatemala; at least thirty-six fatalities were directly attributed to the tropical depression itself, with many more in Central America being blamed on the overall weather system. On the same day that made landfall, Hurricane Jova came ashore further to the west, in the Mexican state of Jalisco, at Category 2 strength; high winds and heavy rains killed nine people and caused at least MX$3.164 billion (US$254.3 million) in losses. Hurricane Beatriz in June claimed four lives when it passed a short distance off the Mexican state of Colima, producing strong winds and locally significant flooding on land. Hurricanes Adrian in early June, Dora in July, and Hilary in late September all threatened or brushed the Pacific coast of Mexico but only caused minor peripheral effects.

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 and the Central Pacific 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. Prior to 2015, two time zones were utilized in the Eastern Pacific basin: Pacific east of 140°W, and Hawaii−Aleutian from 140°W to the International Date Line. 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 of events

May May 15 The 2011 East Pacific hurricane season officially begins.

June June 1 The 2011 Central Pacific hurricane season officially begins.

June 7

12:00 UTC (5:00 a.m. PDT) at A tropical depression develops from an area of low pressure about 370 mi (595 km) south of Acapulco, Guerrero.

June 8 00:00 UTC (5:00 p.m. PDT, June 7) at The aforementioned tropical depression strengthens into Tropical Storm Adrian about 355 mi (575 km) south of Acapulco, Guerrero.

June 9 00:00 UTC (5:00 p.m. PDT, June 8) at Tropical Storm Adrian strengthens into a Category 1 hurricane about 270 mi (435 km) south-southwest of Acapulco, Guerrero. 12:00 UTC (5:00 a.m. PDT) at Hurricane Adrian strengthens to Category 2 intensity about 310 mi (500 km) southwest of Acapulco, Guerrero. 18:00 UTC (11:00 a.m. PDT) at Hurricane Adrian strengthens to Category 3 intensity about 350 mi (565 km) west-southwest of Acapulco, Guerrero, making it the first major hurricane of the season.

June 10

00:00 UTC (5:00 p.m. PDT, June 9) at Hurricane Adrian strengthens to Category 4 intensity about 395 mi (640 km) west-southwest of Acapulco, Guerrero; it simultaneously attains peak winds of 140 mph (220 km/h). 06:00 UTC (11:00 p.m. PDT, June 9) at Hurricane Adrian attains a minimum barometric pressure of about 445 mi (715 km) west-southwest of Acapulco, Guerrero. 18:00 UTC (11:00 a.m. PDT) at Hurricane Adrian weakens to Category 3 intensity about 530 mi (850 km) south-southeast of Cabo San Lucas, Baja California Sur.

June 11 06:00 UTC (11:00 p.m. PDT, June 10) at Hurricane Adrian rapidly weakens to Category 1 intensity, skipping Category 2 status, about 500 mi (805 km) south of Cabo San Lucas, Baja California Sur. 18:00 UTC (11:00 a.m. PDT) at Hurricane Adrian weakens into a tropical storm about 530 mi (850 km) south-southwest of Cabo San Lucas, Baja California Sur.

June 12 12:00 UTC (5:00 a.m. PDT) at Tropical Storm Adrian degenerates into a post-tropical cyclone about 570 mi (915 km) southwest of Cabo San Lucas, Baja California Sur.

June 19 06:00 UTC (11:00 p.m. PDT, June 18) at A tropical depression develops from an area of low pressure about 265 mi (425 km) south-southeast of Acapulco, Guerrero. 18:00 UTC (11:00 a.m. PDT) at The tropical depression strengthens into Tropical Storm Beatriz about 195 mi (315 km) south-southwest of Acapulco, Guerrero.

June 20 18:00 UTC (11:00 a.m. PDT) at Tropical Storm Beatriz strengthens into a Category 1 hurricane about 190 mi (305 km) south-southeast of Manzanillo, Colima.

June 21

06:00 UTC (11:00 p.m. PDT, June 20) at Hurricane Beatriz attains peak winds of 90 mph (150 km/h) and a minimum barometric pressure of about 45 mi (75 km) south-southeast of Manzanillo, Colima. Within the next three hours, the eye of Beatriz passes within 15 mi (30 km) of the Pacific coast of Mexico. 12:00 UTC (5:00 a.m. PDT) at Hurricane Beatriz weakens into a tropical storm about 45 mi (75 km) west of Manzanillo, Colima.

June 22 00:00 UTC (5:00 p.m. PDT, June 21) at Tropical Storm Beatriz weakens into a tropical depression about 105 mi (165 km) west of Manzanillo, Colima; it dissipates six hours later.

July July 7 12:00 UTC (5:00 a.m. PDT) at A tropical depression develops from an area of low pressure about 175 mi (280 km) southwest of Acapulco, Guerrero.

July 8 00:00 UTC (5:00 p.m. PDT, July 7) at The aforementioned tropical depression strengthens into Tropical Storm Calvin about 205 mi (335 km) southwest of Zihuatanejo, Guerrero. 18:00 UTC (11:00 a.m. PDT) at Tropical Storm Calvin strengthens into a Category 1 hurricane about 305 mi (490 km) southwest of Manzanillo, Colima.

July 9

00:00 UTC (5:00 p.m. PDT, July 8) at Hurricane Calvin attains peak winds of 80 mph (130 km/h) and a minimum barometric pressure of about 350 mi (565 km) west-southwest of Manzanillo, Colima. 12:00 UTC (5:00 a.m. PDT) at Hurricane Calvin weakens into a tropical storm about 270 mi (435 km) east-southeast of Clarion Island.

July 10 06:00 UTC (11:00 p.m. PDT, July 9) at Tropical Storm Calvin degenerates into a post-tropical cyclone about 115 mi (185 km) east-southeast of Clarion Island.

July 18 06:00 UTC (11:00 p.m. PDT, July 17) at A tropical depression develops from an area of low pressure about 240 mi (390 km) south-southwest of San Salvador, El Salvador. 12:00 UTC (5:00 a.m. PDT) at The tropical depression strengthens into Tropical Storm Dora about 260 mi (415 km) south-southwest of San Salvador, El Salvador.

July 19 18:00 UTC (11:00 a.m. PDT) at Tropical Storm Dora strengthens into a Category 1 hurricane about 245 mi (400 km) south-southwest of Puerto Escondido, Oaxaca.

July 20 12:00 UTC (5:00 a.m. PDT) at Hurricane Dora strengthens to Category 2 intensity about 340 mi (545 km) south-southeast of Manzanillo, Colima. 18:00 UTC (11:00 a.m. PDT) at Hurricane Dora strengthens to Category 3 intensity about 275 mi (445 km) south of Manzanillo, Colima, making it the second major hurricane of the season.

July 21 00:00 UTC (5:00 p.m. PDT, July 20) at Hurricane Dora strengthens to Category 4 intensity about 230 mi (370 km) south of Manzanillo, Colima. 12:00 UTC (5:00 a.m. PDT) at Hurricane Dora attains peak winds of 155 mph (250 km/h) and a minimum barometric pressure of about 205 mi (335 km) southwest of Manzanillo, Colima, making it the strongest storm of the season.

July 22 06:00 UTC (11:00 p.m. PDT, July 21) at Hurricane Dora rapidly weakens to Category 2 intensity, skipping Category 3 status, about 275 mi (445 km) west of Manzanillo, Colima. 12:00 UTC (5:00 a.m. PDT) at Hurricane Dora weakens to Category 1 intensity about 265 mi (425 km) south of the southern tip of the Baja California peninsula. 18:00 UTC (11:00 a.m. PDT) at Hurricane Dora weakens into a tropical storm about 225 mi (360 km) south of the southern tip of the Baja California peninsula.

July 24 12:00 UTC (5:00 a.m. PDT) at Tropical Storm Dora weakens into a tropical depression about 255 mi (410 km) west of the southern tip of the Baja California peninsula.

July 25 00:00 UTC (5:00 p.m. PDT, July 24) at Tropical Depression Dora degenerates into a remnant low about 310 mi (500 km) west-northwest of the southern tip of the Baja California peninsula.

July 31

06:00 UTC (11:00 p.m. PDT, July 30) at A tropical depression develops from an area of low pressure about 445 mi (715 km) south of Acapulco, Guerrero. 12:00 UTC (5:00 a.m. PDT) at The tropical depression strengthens into Tropical Storm Eugene about 430 mi (695 km) south of Acapulco, Guerrero.

August August 1 18:00 UTC (11:00 a.m. PDT) at Tropical Storm Eugene strengthens into a Category 1 hurricane about 450 mi (725 km) southwest of Acapulco, Guerrero.

August 2 18:00 UTC (11:00 a.m. PDT) at Hurricane Eugene strengthens to Category 2 intensity about 615 mi (990 km) south of the southern tip of the Baja California peninsula.

August 3

06:00 UTC (11:00 p.m. PDT, August 2) at Hurricane Eugene strengthens to Category 3 intensity about 565 mi (910 km) south-southwest of the southern tip of the Baja California peninsula, making it the third major hurricane of the season. 18:00 UTC (11:00 a.m. PDT) at Hurricane Eugene strengthens to Category 4 intensity about 585 mi (935 km) south-southwest of the southern tip of the Baja California peninsula. 21:00 UTC (2:00 p.m. PDT) at Hurricane Eugene attains peak winds of 140 mph (220 km/h) and a minimum barometric pressure of about 595 mi (955 km) southwest of the southern tip of the Baja California peninsula.

August 4 06:00 UTC (11:00 p.m. PDT, August 3) at Hurricane Eugene weakens to Category 3 intensity about 640 mi (1,030 km) southwest of the southern tip of the Baja California peninsula. 18:00 UTC (11:00 a.m. PDT) at Hurricane Eugene weakens to Category 2 intensity about 740 mi (1,195 km) southwest of the southern tip of the Baja California peninsula.

August 5 00:00 UTC (5:00 p.m. PDT, August 4) at Hurricane Eugene weakens to Category 1 intensity about 795 mi (1,280 km) west-southwest of the southern tip of the Baja California peninsula. 12:00 UTC (5:00 a.m. PDT) at Hurricane Eugene weakens into a tropical storm about 915 mi (1,475 km) west-southwest of the southern tip of the Baja California peninsula.

August 6 12:00 UTC (5:00 a.m. PDT) at Tropical Storm Eugene degenerates into a post-tropical cyclone about 1,175 mi (1,890 km) west-southwest of the southern tip of the Baja California peninsula.

August 15