Typhoon Melor (#18) is heading towards Japan and could be the worst storm to hit Japan in more than 10 years. JAL has canceled/delayed some of the flights due to this. So far NRT and KIX are not seeing delays today but could see the impact starting tomorrow. However Chubu (Nagoya) are expected to start seeing impacts on flights today. You should definitely check JAL website (international, domestic) for the latest flight information before your flights. You can also check the typhoon information here.

Source: Reuters