Originally Posted by
djpjapan
To throw a spanner in the works ... if you get a snow storm in Tokyo you are in trouble too.
I got stuck in CTS in Jan this year for about 8 hours - snow everywhere all the time in Sapporo but Tokyo isn't used to it and the airports were closed. Everything was cancelled for hours and CTS was chaos with how to get rid of all the people. Narita flights were running again before Haneda .. but everyone was on standby and almost all foreigners missed their connections.
Anomalies of snow, etc aside I think you will be fine but have never done it myself
True, but the snowstorm you are referring to is the only big one Tokyo has had in a few years... about 777s / hour for both JL and ANA adds up quick in terms of people in CTS.