The Herald News: Fall River police deputy chief to lead department starting immediately
The Herald News: Fall River Police Chief Kelly Furtado to retire amid contract debate
Fall River Mayor Paul Coogan picked a 14-year veteran of the police department to serve as interim chief hours after Kelly Furtado stepped down.
Fall River Police Chief Kelly Furtado, the city's first woman chief, is retiring after 38 years, citing political pressure.
Today means "the current day", so if you're asking what day of the week it is, it can only be in present tense, since it's still that day for the whole 24 hours. In other contexts, it's okay to say, for example, "Today has been a nice day" nearer the end of the day, when the events that made it a nice day are finished (or at least, nearly so).
tenses - Today Was vs Today Is - English Language & Usage Stack Exchange
Today had been the worst day of my life. seems awkward, as today is not understood to mean on this day (the original meaning). In narrative, an event that is happened in the past is narrated as it is the present, as in: It is the 1st of April, 2006. Today will be the worst day of my life. Outside that specific context, I would write
Neither are clauses, but "today in the afternoon" is grammatical (adverbial phrase of time), while "today afternoon" is not. I would also suggest "this afternoon" as a more succinct and idiomatic alternative to "today in the afternoon".
word choice - 'Today afternoon' vs 'Today in the afternoon'? - English ...