Literary or Wu-dialect (Shanghainese, Suzhou-hua) word for "today/now". In Mandarin standard, 今天 has replaced it in everyday speech. You'll meet 今朝 in poetry, classical chengyu, song lyrics, and Mao Zedong's 《沁园春·雪》: "数风流人物，还看今朝."
mistakes
Don't read 朝 as cháo here - that's the "dynasty/court" reading. In 今朝 ("this morning/today"), 朝 is zhāo, the "morning" reading.
