Hurricane Agatha Nears Southern Mexico

Hurricane Agatha neared southern Mexico on Monday morning. At 8:00 a.m. EDT on Monday the center of Hurricane Agatha was located at latitude 15.1°N and longitude 97.3°W which put it about 65 miles (105 km) southwest of Puerto Angel, Mexico. Agatha was moving toward the northeast at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 110 m.p.h. (175 km/h) and and there were wind gusts to 130 m.p.h. (210 km/h). The minimum surface pressure was 964 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.

Hurricane Agatha did not change much during Sunday night. A small circular eye was present at the center of Hurricane Agatha. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Agatha. Storms near the core generated strong upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Agatha was small. Winds to hurricane force extended out 20 miles (30 km) from the center of Agatha’s circulation. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Agatha was 19.2. The Hurricane Size Index (HSI) was 7.3 and the Hurricane Wind Intensity Size Index (HWISI) was 26.5. The intensity of Hurricane Agatha was the same as the intensity of Hurricane Sally when Sally hit northwest Florida in 2020. Agatha was smaller than Sally was.

Hurricane Agatha will move through an environment favorable for intensification during the next few hours. Agatha will move over water where the Sea Surface Temperatures are near 29˚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 could strengthen a little before it reaches Mexico. An upper level trough over Baja California will approach Agatha as the hurricane makes landfall on the coast of Mexico. 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. The circulation around Hurricane Agatha could pull drier air over Mexico into the western part of Agatha. More vertical wind shear and drier air could cause Hurricane Agatha to start to weaken just prior to landfall.

The upper level trough over Baja California will steer Agatha toward the northeast more quickly on Monday. On its anticipated track, Hurricane Agatha will make landfall on the coast of Mexico near Puerto Escondido and Puerto Angel in a few hours. Hurricane Agatha will bring strong winds and locally heavy rain to Oaxaca and Chiapas. Heavy rain is likely to cause flash floods in some locations. Agatha could produce a storm surge of ten feet (three meters) along portions of the coast of Oaxaca. Hurricane Agatha could cause localized serious damage.