Using the contraction "there's" to refer to a plural noun; i.e. "There's storms on the way for later in the week." It should be "There are storms on the way for later in the week." Storms is a plural. You would never say, "There is storms," would you? I hope not. Use of the contracted form is no different! This particular error is no less annoying because I find myself using it now and then. I should know better, and I usually correct myself (sometimes very vehemently), much to the amusement of my co-workers.
But what's really starting to bother me is that I'm now seeing this incorrect usage crop up in legitimate news articles, by journalists! Journalists should know better, especially when it comes to the written word! What are they teaching in these schools? What is wrong with you people?!?