IMD on Sunday issued orange and yellow alerts for several districts, warning of heavy to very heavy rain and thunderstorms between August 10 and August 14. According to the weather department, heavy rain is likely to occur at isolated places in Bageshwar, Dehradun, Tehri, Pauri, Uttarkashi, Rudraprayag, Nainital, Udham Singh Nagar and Champawat districts of Uttarakhand.