TreniNord departs (mostly) out of Cadorna, the station flanking the Sforza Castle, and runs "nord"--north--to places such as (lovely) Como.
Just in time for Christmas visits and shopping (mean! mean! mean!), the workers are planning strikes.
Friday, the 12th of December the strike will be from 9 A.M. to 5 P.M. (in truth, this should spare many commuters), but ATM is also involved, though other sources say ATM will stop from 7 P.M. onwards. Your guess is as good as mine.
Saturday and Sunday the 12th and 14th of December, the trains stop at 9 P.M., and even if your train leaves before 9 P.M., if it doesn't get to your destination by 10 P.M., you're fried.
Get out your walking shoes, and hope that the clouds don't produce rain.
I can hardly say my usual "Enjoy!," can I?