Overview

• Mexico’s water and weather agencies are monitoring a low-pressure area off Guerrero, Oaxaca and Chiapas with a 40% probability of tropical cyclogenesis within seven days.
• If the disturbance organizes, it would be named Sonia and become the 18th named system of the eastern Pacific season.
• From October 14 to 16, interaction between the disturbance, low-pressure channels and an upper-level circulation is expected to deliver heavy to locally intense rainfall in Oaxaca and Chiapas, heightening risks of flash floods and landslides.
• A separate low-pressure trough over the Sierra Madre Occidental, moisture from the Pacific and Gulf, tropical wave No. 37 and an incoming cold front are forecast to spread showers, storms and strong winds across northern, central and western Mexico.
• This season has produced 17 named Pacific cyclones to date, and authorities project up to 20 overall with several potentially reaching major hurricane strength.