今日だ。（きょうだ。）[kyohh-da] "(is) Today." To use as a topic for a sentence, one can start with 「今日は…」 Meaning "as for today..." or "with regards to today..." [kyohh-wa ...] For example, "today has great weather" could be rendered as 「今日はいい天気だね。」（きょうはいいてんきだね。）[kyohh-wa, ii ten-ki da ne]