In case you haven't noticed, Bangkok's weather in January was pretty cool. It could drop to about 18 C (or possibly lower) at night. No need use fan or aircon while sleeping.
It was also a great time to have a picnic in the park. Sitting under the shade was quite nice and cooling. Though the grass (and some trees) in the park look kinda brown and dead.
Going to the park is easy. Its just beside Chatuchak weekend market (no, not Chatuchak Park, but the one further accross it). Its called Rot Fai park or Queen Sirikit Park (maybe its different, but who cares). When you're there, its can be pretty confusing for the first time - try telling your friend to find you behind the tree, beside that big patch of green grass.
Anyway, miraculously, we found each other. And we actually had healthy food for the picnic!
It was also kitty's first outing.
(no, not advisable to bring a kitty out just like that, it has to be trained or at least leash-trained. Otherwise you run the risk of losing kitty)
If you have a helicopter, you can fly it in the park - provided its not too windy, and you don't mind breaking the tail off.
There's small bodies of water everywhere. Some places you can row boats, I think. Otherwise, there's always dragonflies to chase after.
The best part is that, with all the pollution in the skies, the sunsets are always nice :)