|Above: Preliminary track map for the 2017 Eastern Pacific hurricane season. Image credit: NHC.|
The 2017 Eastern Pacific hurricane season, which runs from May 15 to November 30, is in the books. The amount of death and destruction was lower than usual, though 2017 had above-average activity: 18 named storms, 9 hurricanes, and 4 major hurricanes. The averages from 1971 – 2009 were 15 named storms, 8 hurricanes, and 3 major hurricanes. The 2017 numbers fell within the range of the May pre-season prediction by the National Oceanic and Atmospheric Administration (NOAA), which called for an 80% chance of 14 - 20 named storms, 6 - 11 hurricanes, and 3 - 7 major hurricanes. The May forecast by Mexico’s Servicio Meteorológico Nacional (SMN) called for 16 named storms, 10 hurricanes and 6 major hurricanes.
Five Eastern Pacific named storms made landfall, including one in El Salvador (Tropical Storm Selma), and four in Mexico: Tropical Storm Beatriz, Tropical Storm Calvin, Tropical Storm Lidia, and Category 1 Hurricane Max. Total damages from the landfalling storms were in the millions of dollars, as estimated by insurance broker Aon Benfield. The total death toll was 28. For the first year since 2012, no tropical cyclones threatened Hawaii. Some of the notable storms of the 2017 Eastern Pacific hurricane season are highlighted below.
|Figure 1. Tropical Depression One-E as seen on Tuesday afternoon, May 9, 2017, by the VIIRS instrument on the Suomi satellite. At the time, the storm was the earliest tropical depression ever observed in the Eastern Pacific; the system became Tropical Storm Adrian later that evening. Image credit: NASA.|
Adrian becomes the earliest Eastern Pacific named storm on record
The Eastern Pacific hurricane season got off to a record-early start in 2017 when Tropical Depression One-E formed off the coast of Mexico on May 9, becoming Tropical Storm Adrian later that evening. Adrian dissipated after just one day as a tropical storm. The previous earliest appearance of a tropical depression in the Eastern Pacific (since reliable satellite records began in 1970) was on May 12, 1990, when Tropical Storm Alma got its start. Three other systems got their start as tropical depressions on May 13, according to NOAA’s Historical Hurricane Tracks website. The previous earliest appearance of a tropical storm in the Eastern Pacific was on May 14, 1990 (Tropical Storm Alma.) As we discussed in detail in May, hurricane season appears to be lengthening in parts of the North Atlantic, but there is no research confirming any significant changes in season length in the Eastern Pacific.
|Figure 2. The only landfalling Eastern Pacific hurricane of 2017, Category 1 Hurricane Max, as seen on September 14, 2017, shortly before making landfall on the Guerrero coast of Mexico. Image credit: NASA.|
Beatriz, Calvin, Lidia and Max hit Mexico
Tropical Storm Beatriz made landfall about 20 miles west of Puerto Ángel, Mexico on June 2, with top winds of 45 mph. Beatriz quickly dissipated over the mountainous terrain of Mexico, but dumped torrential rains that led to flash floods and landslides that killed 6 people.
Tropical Storm Calvin made landfall about 45 miles south-southwest of Salina Cruz, Mexico on June 13, with top winds of 45 mph, but caused no loss of life. Heavy rains associated with the tropical storm flooded portions of the state of Oaxaca, damaging roads and causing several million dollars in damage.
Tropical Storm Lidia made landfall on September 1, 2017, on the west side of Mexico’s Baja Peninsula, with top sustained winds of 65 mph. Lidia was the deadliest Eastern Pacific storm of 2017, with 20 deaths.
Hurricane Max hit the Guerrero coast of Mexico on September 14, 2017, as a Category 1 hurricane with 85 mph winds. Max’s heavy rains caused flash floods that killed two people and caused millions in damage.
Selma becomes the first named storm on record to hit El Salvador
Tropical Storm Selma formed on October 27 from a large area of low pressure called a Central American Gyre, which also helped spawn Atlantic Tropical Storm Philippe at the same time. Selma made landfall just southeast of San Salvador, El Salvador, on October 28 with top winds of 40 mph, becoming the first Eastern Pacific tropical cyclone to make landfall anywhere in El Salvador. Selma’s rains are not being directly blamed for any damage or deaths, but heavy rains produced by Selma’s remnants, in combination with a cold front, resulted in flooding that killed seven people in Honduras and ten in Nicaragua.