A storm in the Caribbean has been upgraded to a hurricane and is threatening Costa Rica and southern Nicaragua, forecasters say.
They warned that Hurricane Otto may have winds of 90 mph (145km/h) when it makes landfall early on Thursday.
At least four people have already died in Panama in severe weather caused by the approach of the storm.
The hurricane is moving west at 2 mph (4km/h) after being almost stationary throughout Tuesday, experts say.
The US National Hurricane Center says Otto is now blowing at about 75 mph (120km/h) as it approaches northern Costa Rica and southern Nicaragua.
The storm is now centred east of Limon, Costa Rica. When it makes landfall early on Thursday its heavy rain is expected to create numerous mudslides. It is then expected to cross over into the Pacific,
"A storm of Otto's expected strength has never made landfall so far south in the Caribbean, and there is no record of any hurricane striking Costa Rica," the Washington Post quoted weather expert Bob Henson as saying.
The paper says that very few hurricanes have formed so late in the season - which ends on 30 November - and that across the Atlantic since 1851 only 35 storms have reached tropical storm intensity on or after 15 November.
Earlier in Panama two people died in a mudslide; a girl drowned in a river and a boy died when a tree fell on a car taking him to school. His mother, who was driving, survived.
About 50 homes were destroyed by mudslides, officials said, and flights were delayed.
The governments of Nicaragua and Costa Rica have issued a hurricane watch from Costa Rica's southern border to the city of Bluefields in Nicaragua.
There is also a likelihood of dangerous surf and rip current conditions over the next few days along the coasts of Panama, Costa Rica and Nicaragua, officials say.