Former Tropical Storm Agatha strengthened to a hurricane over the Eastern North Pacific Ocean south of Mexico on Sunday morning. At 8:00 a.m. EDT on Sunday the center of Hurricane Agatha was located at latitude 14.1°N and longitude 99.0°W which put it about 200 miles (320 km) west-southwest of Puerto Angel, Mexico. Agatha was moving toward the north-northwest at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 75 m.p.h. (120 km/h) and and there were wind gusts to 90 m.p.h. (145 km/h). The minimum surface pressure was 987 mb.
A Hurricane Warning was in effect for the portion of the coast from Salina Cruz to Lagunas de Chacahua, Mexico. A Hurricane Watch was in effect for the portion of the coast from Salina Cruz to Barra de Tonala. Tropical Storm Warnings were in effect for the portions of the coast from Lagunas de Chacahua to Punta Maldonado and from Salina Cruz to Boca de Pijijiapan, Mexico.
The center of circulation at the surface of former Tropical Storm Agatha moved under the center of circulation in the middle troposphere early on Sunday. The improved vertical structure allowed Agatha to strengthen to a hurricane. Microwave satellite images indicated that a small eye was forming at the center of Hurricane Agatha. The developing eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring. Bands of showers and thunderstorms were in the southern and eastern parts of Agatha’s circulation. Bands in the northwestern part of Hurricane Agatha consisted primarily of showers and lower clouds. Storms near the center of Agatha generated upper level divergence that pumped mass away from the hurricane. Winds to hurricane force extended out 20 miles (30 km) from the center of Agatha. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation.
Hurricane Agatha will move through an environment favorable for intensification during the next 24 hours. Agatha will move over water where the Sea Surface Temperatures are near 30˚C. It will move under the center of an upper level ridge over the Eastern North Pacific Ocean. The upper level winds are weak near the center of the ridge and there will be little vertical wind shear. Hurricane Agatha will intensify during the next 24 hours. Agatha could undergo a period of rapid intensification once an inner core with an eye and an eyewall develop fully. An upper level trough over Baja California will approach Hurricane Agatha on Monday. The upper level trough will produce westerly winds that will blow toward the top of Agatha’s circulation. Those winds will cause the vertical wind shear to increase. More wind shear will make the environment less favorable for intensification.
Hurricane Agatha will move around the western part of a high pressure system over Central America and the Eastern North Pacific Ocean. The high pressure system will steer Agatha toward the north during the next few hours. Agatha will move toward the northeast on Sunday night when it moves around the northwestern part of the high pressure system. The upper level trough over Baja California will steer Agatha toward the northeast more quickly on Monday. On its anticipated track, Hurricane Agatha will move approach the coast of Mexico near Puerto Escondido and Puerto Angel during the middle of Monday. There is a chance Agatha could be a major hurricane when it nears the coast of Mexico. Hurricane Agatha will bring strong winds and locally heavy rain to Oaxaca. Heavy rain is likely to cause flash floods in some locations. Agatha could produce a storm surge of seven feet (two meters) along portions of the coast of Oaxaca.