Checking up on someone’s welfare

Hi /r/houston. I'm hoping I can get your help.

A friend of mine from just outside of Houston has been radio silent for the last week. Last Thursday, she sent a message which looking back is making me worried. She said that "everything is alright… so far" and then has been silent since about 2 hours after that. I haven't been able to get a reply or her answering her calls which is wildly out of character.

I was wondering is there any way of checking up on people that I can do? I'm in Europe so I don't think I'd be able to contact the police. Maybe if there was some community/neighborhood watch or something like that? I'm just very worried about her and I don't have a direct way of contacting her family.

Thank you