experienced this level of heightened flood threat. jim. >> all right, derek van dam, a lot to keep an eye on. we know you'll stay on top of it. thank you very much. if hilary hits southern california as a tropical storm, it will be the first time that has happened in more than 80 years. the sheriff in san bernardino county issued an evacuation warning for several communities. officials are preparing for life-th life-threatening conditions and urging millions of residents to heed their warnings. >> make no mistake, this is a very, very dangerous and significant storm. >> cnn's natasha chen in los angeles for us. i can't believe we're talking about this. and talking about l.a. i mean, it's just so strange to think about this and i hope because it is so bizarre and unusual and historic that people are going to take this seriously, these officials just wrapped up this news conference. what are they saying? >> reporter: yeah, jim, i