Hurricane Norbert has struck Mexico's northwest Pacific coast, ripping off roofs, knocking down trees and leaving one person missing and more than 20 000 homes without electricity, local authorities said.

Norbert, which made landfall as a Category Two hurricane on the five-level Saffir-Simpson scale, came ashore at Puerto Cortes, on the Baja California peninsula at around 4.30pm GMT, Mexico's National Weather Service said.

It was later downgraded to a Category One storm with sustained winds of 150 kilometres per hour winds.

"The entire area is being affected by hurricane strength" winds and downpours, a National Weather Service forecaster said by phone.

"A man trying to cross the Miramar creek has been reported as missing after the current swept him away," the authorities in Loreto, one of the municipalities Norbert tore through, said.

The storm late on Saturday was over Gulf of California waters and expected to make landfall again on mainland Mexico in Sinaloa state at around midnight (5am GMT, Sunday), the Weather Service said.

Some 2850 people were housed in temporary shelters.

Forty percent of homes were totally or partially damaged on the islands of Margarita and Magdalena, mainly having lost their roofs, said a report from state protection services.

In the Baja California capital of La Paz, the storm knocked out power to 13 000 homes, and to 8000 more in Ciudad Constitution, the Federal Electricity Commission reported.

La Paz international airport suspended its activities at midday on Saturday, but the tourist resort of Los Cabos remained open.

Hotel reservations were down by around 40 percent mainly in Los Cabos and Loreto, local tourism officials said.

At 3am GMT, Sunday the eye of Norbert was located about 195 kilometres east-northeast of Loreto, Mexico, the US-based National Hurricane Centre reported.

"Little change in strength is expected until landfall ... then a rapid weakening is forecast over the mountainous terrain of Mexico," the NHC said.

The hurricane however is expected to dump up to 15 centimetres of rain over the peninsula and portions of northwestern Mexico, "with possible isolated amounts of 10 inches (25 centimetres)," the NHC said.

AFP