At around 0500 GMT, Cristina had maximum sustained winds of nearly 165 kilometres per hour and was centred 525 kilometres southwest of the city of Manzanillo, the US National Hurricane Centre said.
It was moving toward the northwest at 13 kilometres per hour.
Cristina is expected to weaken further over the next 48 hours, the Miami-based the centre said.
Classification of a hurricane's strength is based on the one-to-five Saffir-Simpson scale, with five denoting the most intense winds.
At its strongest, Cristina reached category four status yesterday.
The storm continues, however, to generate sizable ocean swells miles away.
"Swells generated by Cristina are affecting portions of the southwestern coast of Mexico. These swells should begin to subside later today," the NHC said.