The 2013 Pacific hurricane season was an above-average year in which twenty named storms developed. The hurricane season officially began on May 15 in the East Pacific, coinciding with the formation of Tropical Storm Alvin, and on June 1 in the Central Pacific; it ended on November 30 in both basins. These dates conventionally delimit the period during each year when most tropical cyclones form. The final system of the year, Tropical Storm Sonia, dissipated on November 4.

The season produced twenty-one tropical depressions. All but one further intensified into tropical storms and nine further intensified to become hurricanes. Despite this level of activity, only one hurricane, Raymond, strengthened into a major hurricane. During the season, five named storms made landfall in Mexico: hurricanes Barbara and Manuel, along with tropical storms Juliette, Octave, and Sonia.

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

May May 15

The 2013 East Pacific hurricane season officially begins. 0600 UTC (11:00 p.m. PDT May 14) – Tropical Depression One-E develops from an area of low pressure about 650 mi (1,045 km) south-southwest of Acapulco, Mexico, becoming the second lowest-latitude-forming tropical cyclone on record. 1800 UTC (11:00 a.m. PDT) – Tropical Depression One-E intensifies into Tropical Storm Alvin roughly 665 mi (1,070 km) south-southwest of Acapulco, Mexico. May 16 0600 UTC (11:00 p.m. PDT May 15) – Tropical Storm Alvin attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 1000 mb (hPa; 29.53 inHg) about 705 mi (1,135 km) southwest of Acapulco, Mexico. May 17 0600 UTC (11:00 p.m. PDT May 16) – Tropical Storm Alvin dissipates roughly 775 mi (1,245 km) southwest of Manzanillo, Mexico. May 28 1200 UTC (5:00 a.m. PDT) – Tropical Depression Two-E develops from an area of low pressure about south-southeast of Puerto Ángel, Mexico. 1800 UTC (11:00 a.m. PDT) – Tropical Depression Two-E intensifies into Tropical Storm Barbara roughly south-southeast of Puerto Ángel, Mexico. May 29

1200 UTC (5:00 a.m. PDT) – Tropical Storm Barbara intensifies into a Category 1 hurricane about southeast of Salina Cruz, Mexico. 1950 UTC (12:50 p.m. PDT) – Hurricane Barbara attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 983 mb (hPa; 29.03 inHg) and simultaneously makes landfall roughly west-southwest of Tonalá, Mexico, becoming the easternmost landfalling Pacific hurricane on record. May 30 0000 UTC (5:00 p.m. PDT May 29) – Hurricane Barbara weakens to a tropical storm about east of Cintalapa. 0600 UTC (11:00 p.m. PDT May 29) – Tropical Storm Barbara weakens to a tropical depression roughly southwest of Villahermosa, Mexico. 1200 UTC (5:00 a.m. PDT) – Tropical Depression Barbara degenerates into a non-convective remnant area of low pressure about east-northeast of Coatzacoalcos, Mexico.

June June 1 The 2013 Central Pacific hurricane season officially begins. June 23 1200 UTC (5:00 a.m. PDT) – Tropical Depression Three-E develops from an area of low pressure about south of Manzanillo, Mexico. June 24 0000 UTC (5:00 p.m. PDT June 23) – Tropical Depression Three-E intensifies into Tropical Storm Cosme roughly south-southwest of Zihuatanejo, Mexico. June 25

1200 UTC (5:00 a.m. PDT) – Tropical Storm Cosme intensifies into a Category 1 hurricane about southwest of Manzanillo, Mexico. June 26 0000 UTC (5:00 p.m. PDT June 25) – Hurricane Cosme attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 980 mb (hPa; 28.94 inHg). 1800 UTC (11:00 a.m. PDT) – Hurricane Cosme weakens to a tropical storm roughly 465 mi (750 mi) southwest of the southern tip of Baja California. June 27 1200 UTC (5:00 a.m. PDT) – Tropical Storm Cosme degenerates into a non-convective remnant area of low pressure about 690 mi (1,110 km) west-southwest of Cabo San Lucas, Mexico. June 29 1800 UTC (11:00 a.m. PDT) – Tropical Depression Four-E develops from an area of low pressure roughly south of Manzanillo, Mexico. June 30 0600 UTC (11:00 p.m. PDT June 29) – Tropical Depression Four-E intensifies into Tropical Storm Dalila about southwest of Acapulco, Mexico.

July July 2

1200 UTC (5:00 a.m. PDT) – Tropical Storm Dalila intensifies into a Category 1 hurricane roughly south-southwest of Cabo Corrientes, Mexico. 1800 UTC (11:00 a.m. PDT) – Hurricane Dalila attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 984 mb (hPa; 29.06 inHg). July 3 1800 UTC (11:00 a.m. PDT) – Hurricane Dalila weakens to a tropical storm about southwest of Manzanillo, Mexico. July 4 1200 UTC (5:00 a.m. PDT) – Tropical Depression Five-E develops from an area of low pressure roughly southeast of Acapulco, Mexico. July 5 0000 UTC (5:00 p.m. PDT July 4) – Tropical Storm Dalila weakens to a tropical depression about west-southwest of Manzanillo, Mexico. 0000 UTC (5:00 p.m. PDT July 4) – Tropical Depression Five-E intensifies into Tropical Storm Erick roughly south of Acapulco, Mexico. July 6

0600 UTC (11:00 p.m. PDT July 5) – Tropical Storm Erick intensifies into a Category 1 hurricane about southwest of Zihuatanejo, Mexico. 1200 UTC (5:00 a.m. PDT) – Hurricane Erick attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 983 mb (hPa; 29.03 inHg). July 7 0600 UTC (11:00 p.m. PDT July 6) – Tropical Depression Dalila degenerates into a non-convective remnant area of low pressure roughly south-southwest of Cabo San Lucas, Mexico. 1800 UTC (11:00 a.m. PDT) – Hurricane Erick weakens to a tropical storm about west-southwest of Puerto Vallarta, Mexico. July 9 0600 UTC (11:00 p.m. PDT July 8) – Tropical Storm Erick degenerates into a non-convective remnant area of low pressure roughly southwest of La Paz, Mexico. July 25 0000 UTC (5:00 p.m. PDT July 24) – Tropical Depression Six-E develops from an area of low pressure about 980 mi 1,575 km) west-southwest of the southern tip of Baja California. 0600 UTC (11:00 p.m. PDT July 24) – Tropical Depression Six-E intensifies into Tropical Storm Flossie roughly 1,040 mi (1,675 km) southwest of the southern tip of Baja California. July 27 1200 UTC (5:00 a.m. PDT) – Tropical Storm Flossie attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 994 mb (hPa; 29.36 inHg). ~1800 UTC (~11:00 a.m. PDT) – Tropical Storm Flossie crosses 140°W, entering the jurisdiction of the Central Pacific Hurricane Center.

July 30 0000 UTC (5:00 p.m. PDT July 29) – Tropical Storm Flossie weakens to a tropical depression about northeast of Maui, Hawaii. 1200 UTC (5:00 a.m. PDT) – Tropical Depression Flossie degenerates into a non-convective remnant area of low pressure roughly of Kauai, Hawaii. 1200 UTC (5:00 a.m. PDT) – Tropical Depression Seven-E develops from an area of low pressure about 1,025 mi (1,650 km) south-southwest of the southern tip of Baja California. 1800 UTC (11:00 a.m. PDT) – Tropical Depression Seven-E intensifies into Tropical Storm Gil roughly 805 mi (1,295 km) southwest of the southern tip of Baja California. July 31 1800 UTC (11:00 a.m. PDT) – Tropical Storm Gil intensifies into a Category 1 hurricane about 925 mi (1,490 km) southwest of the southern tip of Baja California.

August August 2

0000 UTC (5:00 p.m. PDT August 1) – Hurricane Gil attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 985 mb (hPa; 29.09 inHg). 1800 UTC (11:00 a.m. PDT) – Hurricane Gil weakens to a tropical storm roughly 1,370 mi (2,205 km) west-southwest of the southern tip of Baja California. August 3 1200 UTC (5:00 a.m. PDT) – Tropical Depression Eight-E develops from an area of low pressure about 1,090 mi (1,755 km) southwest of the southern tip of Baja California. August 4 0000 UTC (5:00 p.m. PDT August 3) – Tropical Depression Eight-E intensifies into Tropical Storm Henriette roughly 1,180 mi (1,900 km) southwest of the southern tip of Baja California. 1200 UTC (5:00 a.m. PDT) – Tropical Storm Gil weakens to a tropical depression about 1,325 mi (2,130 km) east-southeast of the Hawaiian Islands. August 6

~0000 UTC (~5:00 p.m. PDT August 5) – Tropical Depression Gil crosses 140°W, entering the jurisdiction of the Central Pacific. 0600 UTC (11:00 p.m. PDT August 5) – Tropical Depression Gil re-intensifies into a tropical storm roughly 1,055 mi (1,700 km) southeast of the Hawaiian Islands. 0600 UTC (11:00 p.m. PDT August 5) – Tropical Storm Henriette intensifies into a Category 1 hurricane about 1,495 mi (2,405 km) west-southwest of the southern tip of Baja California. 1800 UTC (11:00 a.m. PDT) – Tropical Storm Gil weakens to a tropical depression for a second time roughly 985 mi (1,585 km) southeast of the Hawaiian Islands. August 7 0000 UTC (5:00 p.m. PDT August 6) – Tropical Depression Gil dissipates about 1,065 mi (1,715 km) east-southeast of the Hawaiian Islands. August 8 1800 UTC (11:00 a.m. PDT) – Hurricane Henriette intensifies into a Category 2 hurricane and simultaneously attains its peak intensity with maximum sustained winds of and a minimum barometric pressure of 976 mb (hPa; 28.82 inHg). August 9 ~0000 UTC (~5:00 p.m. PDT August 8) – Hurricane Henriette crosses 140°W, entering the jurisdiction of the Central Pacific Hurricane Center. 0600 UTC (11:00 p.m. PDT August 8) – Hurricane Henriette weakens to a Category 1 hurricane roughly 945 mi (1,520 km) east-southeast of the Hawaiian Islands. 1200 UTC (5:00 a.m. PDT) – Hurricane Henriette weakens to a tropical storm about 885 mi (1,425 km) southeast of the Hawaiian Islands. August 11 1200 UTC (5:00 a.m. PDT) – Tropical Storm Henriette weakens to a tropical depression roughly south of Ka Lae, Hawaii. 1800 UTC (11:00 a.m. PDT) – Tropical Depression Henriette degenerates into a non-convective remnant area of low pressure about south-southwest of Ka Lae, Hawaii. August 16 1500 UTC (5:00 a.m. HST) – Tropical Storm Pewa develops from an area of low pressure roughly 1,240 mi (1,995 km) southwest of Lihue, Hawaii.

August 18 ~0600 UTC (~8:00 p.m. HST August 17) – Tropical Storm Pewa crosses the International Date Line and moves into the West Pacific. August 19 0300 UTC (5:00 p.m. HST August 18) – Tropical Storm Unala develops from an area of low pressure about 1,360 mi (2,190 km) west of Honolulu, Hawaii. ~0900 UTC (~11:00 p.m. HST August 18) – Tropical Storm Unala crosses the International Date Line and moves into the West Pacific. 2100 UTC (11:00 a.m. HST) – Tropical Depression Three-C develops from an area of low pressure roughly 1,075 mi (1,730 km) west of Lihue, Hawaii. August 20 ~1500 UTC (~5:00 a.m. HST) – Tropical Depression Three-C crosses the International Date Line and moves into the West Pacific basin. August 22