PHOENIX (3TV/CBS 5) – It was a nice start to our morning, with a low of 54 degrees. That’s seven degrees above average for this time of year. We have a strong ridge of high pressure that is going to keep temperatures well above average for the next few days. Today’s high is expected to be around 78 degrees when our average high this time of year is 69. We could even see the Valley hit 80 degrees on Tuesday, as this high pressure is expected to hold strong through Thursday. And that’s when big changes move in.