I have a gray tabby cat about 16 month old. She was a stray so I'm not sure of her age. We went away this week-end for an overnight trip. Left her and my calico in the house together. When we came home of course she immediately wanted to go out (they are outside about 40% of the time, never at night). When she came back in she started meowing very loudly and running to her food bowl. I fed her so she's not hungry. She never meows like this before. She doesn't seem hurt. Tried to let her out again but she didn't want to go (it's cold). What could this constant meowing mean.

I don't know anything about cats, excpet I love to pet them and hear them purrr.

But I do know that you need to ask questions about cats, under the cat area not the computer area. So I have moved your question to the correct area.

Has she been fixed?

Watch her eating, drinking and urine output if posssible. Also if she gets off to herself that is a sign of illness as well constantly licking her private area and peeing outside the litter box. As homegirl mentioned if she is not spayed constant meowing can be a sign of being in heat. I doubt if being in heat is the case, since most cats in cold area's go into heat from Jan-Feb to Sept. If she did this for more than 2 days I would take her to a vet.

Also, if this is the first time she's been left alone for a while, it could be that she just wants your attention. Will she come snuggle up with you for some scritchles? That might get her back to normal.

My cat meows weirdly after she has a tough bowl movement or is playing and doesn't see anyone around... we call to her and she comes over.. some times they are just vocalizing that they want to see you, or miss you... or are proud of what they did... at first I thought she was hurt but she was fine... if she is acting fine, then I wouldn't worry too much!
Good luck!