From Longman Dictionary of Contemporary Englishsunny/bright intervalssunny/bright intervalsBritish EnglishDN short periods of fine weather between cloudy weather, rainy weather etc → interval
Examples from the Corpus
sunny/bright intervals• East Anglia: Rather cloudy, mainly dry, some sunny intervals.• Many sheltered central and south-eastern areas might stay dry with perhaps some sunny intervals.• Any overnight mist or fog will clear quickly to leave most of the country with sunny intervals and scattered showers.• The day should gradually become dry with sunny intervals.• Outlook for tomorrow and Sunday: Mainly dry and mild, with sunny intervals after clearance of any early mist or fog. 