ON-VEHICLE NAVIGATION APPARATUS, METHOD, AND PROGRAM

PROBLEM TO BE SOLVED: To determine rain with operation of a windshield wiper, and to guide a route for bad weather for a certain period when the road surface is difficult to travel even after stop of the windshield wiper. SOLUTION: This navigation apparatus includes a map information storage section 24, a storage section 19 of a travel caution road during bad weather, a one's own vehicle position detection section 25, a destination setting section 26, and a route guiding section 23 for retrieving and guiding a route to a destination. A weather determination section 20 determines the weather based on the information from a windshield wiper operation monitoring section 16 for monitoring the operation state of the windshield wiper 18. A detection section 21 of a travel caution road during bad weather detects whether a travel caution road during bad weather exists in the route retrieved by the route guiding section 23 when it is bad weather. When the travel caution road during bad weather is detected, the route guiding section 23 retrieves a route avoiding the travel caution road during bad weather. Even when the weather determination section 20 determines fine weather, the route guiding section 23 guides a route avoiding the travel caution road during bad weather for a period set by a continuous guide period setting section 22. COPYRIGHT: (C)2010,JPO&INPIT