Tropical storm Marty gained strength Monday to become a Category 1 hurricane, off the coast of the southwestern Mexican state of Guerrero, the National Meteorological Service, or SMN, announced.
Marty is located 125 km (78 miles) south-southwest of Zihuatanejo and 235 km (146 miles) west of the Port of Acapulco, both in Guerrero, the agency said Monday afternoon.
The hurricane is slowly heading northeast at 9 kph (6 mph), accompanied by maximum sustained winds of 130 kph (81 mph) and gusts as high as 155 kph (96 mph).
The SNM issued a hurricane watch from Tecpan de Galeana, Guerrero, to Lazaro Cardenas, Michoacan.
Marty is expected to produce intense and torrential rainfall in Guerrero and Michoacan, intense rainfall in Oaxaca and very heavy rainfall in the southern states of Jalisco and Colima.
The weather agency also warned of the presence of 3.5-4-meter high (11.5-13-feet) waves off the coasts of Guerrero and Michoacan and up to 4.5-meter high (15 feet) waves in maritime zones.
Experts say until Thursday, Marty could produce between 150 to 300 mm (6 to 12 inches) of rain in Guerrero, and up to 500 mm (20 inches) in the southern part of the state.
The SMN also warned of the possibility of landslides in mountainous regions and floods in low-lying areas and urged residents to take precautions.
Marty will remain a Category 1 hurricane on Tuesday as it approaches the coasts of Guerrero and Michoacan and will be downgraded to a storm Wednesday when it will be 45 km (28 miles) southwest of Zihuatanejo.
Guerrero's civil protection authorities suspended classes in Acapulco and Costa Grande on Monday.
The SMN predicts 19 named cyclones in this year's Pacific hurricane season that began on May 15.
Until now, 13 cyclones have occurred, with two months to go for the end of the hurricane season, on Nov. 30.