Felix made landfall at 8 a.m. EDT north of the small port of Puerto Cabezas, Nicaragua, and was moving westward at 16 mph (26 kph), the U.S. National Hurricane Center said.
Thousands of people hunkered in storm shelters early as Felix, upgraded to an extremely dangerous Category 5 storm, approached the coast provoking fears of a repeat of Hurricane Mitch, which killed some 10,000 people in Central America in 1998.
There could be serious damage and material, like human, losses, if people do not take precautionary measures, Honduran President Manuel Zelaya warned.
The area where Felix hit is sparsely populated and dotted with lagoons and marshes but the storm threatened many poor Honduran and Guatemalan villages further inland that are perched on hillsides and vulnerable to mudslides.
Up to 40,000 Hondurans were evacuated to shelters, but some 15,000 people were unable to find transportation and were forced to ride out the storm in their homes.
They couldn't be evacuated because there is no fuel to take them to safe areas, said Carolina Echeverria, a deputy from Cabo Gracias a Dios on the border with Nicaragua, where Felix landed.
It was too early to predict damage to the region's vital coffee crops. The storm is due to drive through Honduras into Guatemala and then Chiapas in southern Mexico.
Hundreds of tourists were flown to the Honduran mainland from beach and diving resorts on the Bay Islands, and police reported long lines at supermarkets and gas stations in coastal cities as residents stocked up on food, water and fuel.
A storm surge of up to 18 feet was expected.
Emergency workers sailed thousands of Miskito Indians out of sparsely populated, coastal areas near the border, dotted with lagoons and crocodile-infested rivers. The turtle-fishing Miskitos formed a British protectorate until the 19th century. Some 35,000 live in Honduras, and over 100,000 in Nicaragua.
SECOND HUGE STORM
Felix is the second hurricane of the 2007 Atlantic season, and the second Category 5 storm after Hurricane Dean, which killed 27 people in the Caribbean and Mexico in August.
We are faced with a very serious threat to lives and property. The most important thing is that people pay heed to the call for evacuation so that we don't have to count bodies later, said Honduran civil protection head Marco Burgos.
The World Food Program said it had food stocks in the region that could feed 600,000 people for a month.
A Category 5 storm on the five-step Saffir-Simpson scale is capable of catastrophic damage and heavy flooding. Hurricane Katrina, one of the most devastating natural disasters in U.S. history, was a Category 3 when it made landfall near New Orleans in 2005.
Category 5 hurricanes are rare, but there were four in 2005. Others this year could bolster claims that global warming is fueling stronger tropical cyclones.
London coffee futures were broadly higher on Tuesday, in speculative buying with concerns on the impact of Hurricane Felix seen as a factor, dealers said.
In Nicaragua, farmers feared Felix could cause a surge in black beans, which render coffee unexportable and leech nutrients from the soil, as Mitch did. This brings back very difficult memories, said Matagalpa grower Julio Solorzano.
It looked unlikely to re-emerge over the Bay of Campeche, home of Mexico's major offshore oil fields, and strengthen again in the Gulf of Mexico was unclear.
(Additional reporting by Brian Harris and Ivan Castro in Managua and Michael Christie in Miami)