Mexico: Tropical Storm Agatha tracking northeast over Oaxaca State, Mexico, late May 30 /update 4

Event

Tropical Storm Agatha is tracking northeast over Oaxaca State, Mexico, late May 30 following landfall west of Puerto Angel earlier in the afternoon. As of 22:00 CDT, the system's center of circulation was approximately 65 km (40 miles) north-northeast of Puerto Angel, Mexico. Forecast models indicate the system has weakened rapidly and is likely to continue tracking northeastward before dissipating over the eastern part of Oaxaca State early May 31. Some uncertainty remains in the track and intensity forecast, and significant changes could occur over the coming hours.

As of late May 30, Mexican authorities are maintaining a tropical storm warning for Puerto Escondido eastward to Boca de Pijijiapan. Heavy rainfall is likely over portions of southern Mexico through late May 31. Forecast models indicate rainfall of 25-41 cm (10-16 inches) over Oaxaca State, 13-25 cm (5-10 inches) over Chiapas State, and 5-10 cm (2-4 inches) over Veracruz and Tabasco states as well as eastern Guerrero State. The storm surge is forecast to slowly recede late May 30 while the large swells generated by Agatha are likely to affect the coast through May 31. Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming hours.

Authorities in Oaxaca State have set up 200 evacuation shelters with the capacity to house 26,000 people in the coastal area of the state. In Huatulco Region, Oaxaca State, local schools as well as all beaches and bays are closed. Oaxaca and Guerrero ports are also closed. Reports indicate that two highways are impassable due to flooding and landslides and telephone lines have been disrupted in Oaxaca State.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. If weather conditions prove hazardous, localized evacuations, flash flooding, and landslides are possible.

The inclement weather could trigger localized business, transport, and utility disruptions and render some bridges or roadways impassable. Flight disruptions at regional airports and temporary closures of ports are also possible. Stagnant pools of water during and after flooding increase insect- and waterborne diseases, such as dengue fever, cholera, and malaria. Exposure to raw sewage and other hazardous materials mixed with floodwaters poses a serious health threat.

Advice

Activate contingency plans in areas where officials forecast tropical storm conditions. Heed any evacuation orders that may be issued. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents and necessary medications in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks.

Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.

Resources

US National Hurricane Center
National Weather Service
Mexican Meteorological Service (Spanish)