Why is the cold NOT going away?

Not to state the obvious here, but February has been COLD. Most locations in Minnesota and Wisconsin will likely finish the month in the top 15 coldest February's ever, just warmer than last year. The MSP metro is officially 7 degrees below average for the month with St. Cloud coming in at just over 5 degrees shy of average and Eau Claire at nearly 9 degrees. You can see the average temperatures vary wildly across the central US this month with warmer than normal conditions near the Rockies and frigid temperatures for the Great Lakes.

 

 

With about a week to go in the month, you would think there would be some hope in sight on when our drastically cold and dry weather will end, but unfortunately there isn't. So why isn't it going away? Well, the atmosphere is a lot like us really; it can take on a mind of its own, hit you with unexpected curve balls, or get stuck in a rut. That's right; the atmosphere can literally get stuck in a rut kind of like we would get stuck in a routine. It usually takes something drastic for a human to adjust or drop their routine altogether… well the atmosphere is the same way. Right now, it's stuck!

A very large ridge has been sitting up near the Gulf of Alaska for the last few weeks. This has put a kink in the jet stream, forcing a trough to dive south into the eastern U.S. and allowing that cold polar air to plunge southward. Because of this pattern, the eastern U.S. continues to be very cold, while the western U.S. bakes under April-like warmth. Let me show it to you. So the following images show you the location of the jet stream… the river of air at the top levels of the atmosphere that signifies ridges and troughs and ultimately decide where the cold and warm air will end up. Here is what the upper atmosphere looked like on Saturday…

 

The jet stream dips deep into the southwestern U.S. allowing northern flow to take hold and plunge arctic air into the Midwest and Great Lakes. Now look at the forecast for Tuesday…

 

Not quite as cut and dry, with the trough retreating to the northeast a bit. This will allow us to climb out of the deep freeze for a short period of time, but by the end of the week…