-day BrE AmE deɪ, di —Although Received Pronunciation and General American are both traditionally considered to prefer di , most speakers in practice use both pronunciations for this suffix, often in a strong form—weak form relationship. The deɪ form is generally preferred in exposed positions, for example at the end of a sentence: I'll do it on Monday ˈmʌn deɪ ; the di form is preferred in close-knit expressions such as Monday morning ˌmʌnd i ˈmɔːn ɪŋ AmE \ -ˈmɔːrn- .
-DAY
Meaning of -DAY in English
Longman Pronunciation English Dictionary. Английский словарь произношений Longman. 2012