1999 Ford Taurus Starts, 10 Seconds Later Engine/Fan Noise - Safe?

My mother's 1999 Ford Taurus starts then 10 to 15 seconds later there is noise from engine compartment, sounds like a fan running. Tempreture is moderate, in the 60s, this also happens when started in the garage. Need to take a 4 hour drive TODAY, is it safe? Please help. Thank you.