HONOLULU (AP) — The National Weather Service has issued a flash-flood watch effective Monday for Oahu, Maui County and the Big Island as a cold front and air conditions bring the threat of heavy showers, Hawaii News Now reported .

The weather service's office in Honolulu says the watch is expected to run through Tuesday.

The weather service tells Hawaii News Now that the latest computer forecast models show the heaviest showers will take place Monday and Tuesday as the cold front pushes east over the islands. Heavy rain and thunderstorms could become widespread, causing streams to overflow their banks and lead to flash flooding.