By Jeff Ray

(CBSDFW.COM) – For many, Labor Day weekend is considered the last holiday of summer. It will feel like that on Monday.

All that rain and cooler weather of last week took a holiday; expect a breezy day Monday with ample sunshine and highs in the mid 90s. The heat index will close in on 100 degrees so the pool might just seem to be the best place to be in the afternoon.

This bit of warm weather is not to last. I’ve been talking for the last week about the significant change in the overall weather pattern. We are expecting a cool and wet September and got a hint of that since the very first day of the month. Look at the temperatures ahead:

I know you are doing a double take on Wednesday. We haven’t enjoyed a day in the 70s since late May. We are going to skip right over that milestone and have our first day where the highs stay in the 60s all day. That last happened on May 16.

What is happening? Cold Canadian air has been bottled up far north for several weeks. It is finally getting a chance to make its first invasion of the Central Rockies and southern Plains this season.

As crazy as our weather is in North Texas believe me when I say it is nothing compared to living on the front range in Colorado. Denver hits its hottest September day ever recorded Saturday with 101 degrees. They had another 100-degree day there Sunday and expect a high Monday of 93.

At the same time, there is a WINTER ADVISORY out. That is because the very next day they might break a record for the earliest big snow ever. For the hottest September day ever to the earliest snow ever, all in the span of 48 hours. Amazing.

That cold air starts coming into North Texas late Tuesday. We’ll have some unsettled, windy weather with this transition. In just the first week of September, DFW has already piled up more rain than we got in all of August and July:

The storm chances by Tuesday night jump up to 80% as we go from a high of 90 on Tuesday to a high in the 60s the next day. The rain chances stay high through the day on Wednesday and continue into Thursday morning.

On Thursday morning it will be down in the 50s across the Metroplex and our northern counties will likely be in the 40s.

Go ahead and get some of your cold weather gear out, you’ll need it Thursday morning since the north winds will still be rather strong. Weather whiplash indeed.