Hurricane Jova barreled Sunday towards the southwestern Pacific coast of Mexico and forecasters warned it would likely strengthen considerably in the coming days. Mexican authorities warned five states along the west coast to be on guard for possible landslides from heavy rain expected to be dumped by the ninth Pacific hurricane of the season. The Miami-based US National Hurricane Center said in a 2100 GMT bulletin that Jova was a category one on the five-level Saffir-Simpson scale, packing maximum sustained winds of 90 miles per hour (150 kilometers per hour). Jova was forecast to become a major Category 3 hurricane on Monday with winds of up to 120 miles per hour (193 kilometers per hour) but expected to weaken significantly ahead of landfall on Tuesday, the experts said. The massive storm system was currently 305 miles (490 kilometers) southwest of the Mexican coastal city of Manzanillo. Several major storms or hurricanes have buffeted Mexico's Pacific coast in recent months but most have remained offshore. The season's first named storm, Arlene, left at least 16 people dead and drenched much of the country in July. Tropical storms and hurricanes last year caused flooding and mudslides in Mexico that killed 125 people, left hundreds of thousands homeless and caused more than $4 billion in damage.