Weather - fingers crossed it will be mid-50's in the daytime but not too warm at night, especially you will notice the difference if the sun has been out and then it gets dark. Rain is always a possibility and it can get very windy.

All the amusement parks are closed (it is winter!) except for the indoors bit of Zoomarine, which is basically the marine wildlife exhibit. I did read that the zoo at Krazy World had closed down for good at the end of the summer. Otherwise the only zoo is an hour's drive on the other side of Lagos.

If it's a nice sunny day you can always go down to the beach at Salgados and/or have a nice walk around the lake and wildlife reserve. Make the most of it because several new hotels and golf courses are being built there soon.

The Algarve Shopping Mall near Guia, which includes multi-screen cinema and bowling, is open all day every day except that it will close early on December 24th and will be closed all day on the 25th. The Continente hypermarket is also there. Most places incuding bars and restaurants close early on December 24th but you will find a lot of places (but not shops) open on the 25th.

Hope that helps.

if you like swimming, the new municipal baths at Silves are magnificent and cheap.