Hurricane Orlene weakened to a Category 3 storm on Sunday but was still expected to bring severe rain, storm surge and flash flooding to the northwest Pacific coast of Mexico on Monday.

Orlene upgraded to a hurricane on Saturday, peaking as a Category 4 hurricane with maximum sustained winds up to 130 mph by early Sunday before slowing back to 115 mph by midday, the U.S. National Hurricane Center reported.

The center of the storm is likely to pass over the archipelago of Las Islas Marias on Sunday evening or Monday morning, and Orlene is expected to make landfall on the coast of mainland Mexico between San Blas and Mazatlan some time on Monday.

NHC labeled the storm as “extremely dangerous,” forecasting significant rain, storm surge and rainfall impacts in Islas Marias – a former prison colony being developed as a tourist draw – and other parts of southwest Mexico. A hurricane warning was in effect from San Blas to Mazatlan, and Mexico’s National Water Commission warned the storm could cause “mudslides, rising river and stream levels, and flooding in low-lying areas.”

The rainfall amounts in Islas Marias, Nayarit and Sinaloa “will likely lead to flash flooding, as well as possible landslides in areas of rugged terrain,” the center warned.

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