What a spectacular day. I was kayaking off the coast of Harpswell and feeling really fortunate to be able to be in Maine on such a beautiful afternoon. The moon tonight is full and as it illuminates the landscape you’ll hopefully feel the evening is as beautiful as the day.

The humidity was very low today and we didn’t see much in the way of clouds. Across southern New England the amount of moisture in the air is rising and this return to the muggies is just hours away. You might have noticed a few high clouds dotting the sky this afternoon. These cirrus clouds were the forerunner of the warmer and more humid air headed to Maine

This week there’s been a lot of chatter about the return of the polar vortex this week to the Midwest. We could debate the exact definition of the winter polar vortex and whether what is happening meteorologically is the same thing in July, but the bottom line is an unusually pool of cool air is headed for the center of the country over the next few days. When cool air moves into one region of the country, at any time of the year, it causes a downstream reaction of pushing warm air north. Along the boundary between the cool and warm air unsettled weather occurs.

The loop below is the prediction for temperatures at around 5000 feet high. These maps help me to understand how the cool and warm air will move this week. Notice the cool air (blue) trying to move east into the warm air (orange) over the next few days.

Unfortunately for vacationers this week we are going to lose 3 days of sunshine due to the contrast of temperatures and reluctance of the atmosphere to move the dry air back into the region.

Our first opportunity for showers comes Sunday late at night and the first part of Monday. The daylight hours of Sunday look great with a warm and increasingly muggy sort of day. It will be a good day to be at the beach. As the showers role through the areas we could see some heavier downpours. Tuesday and Wednesday also bring a chance of showers and thunderstorms. I don’t feel both days will be total washouts, but Tuesday right now is looking like the wetter of the two. There might be some limited sunshine on that day and a better chance for some sun by Wednesday.

Thursday brings marked improvement as the air dries and sunshine returns. The bulk of the rest of the week will be dry and typically warm for July. A few caveats to this forecast. If the front bringing us the rain moves faster then we will have a better day on Wednesday and if it slows then Thursday becomes impacted. Right now I am playing it in the middle. The key to the forecast will be that cool air in the Midwest and just how fast it can push the humidity out of here later this upcoming week.

How cool will it be for places in parts of Michigan? Check out the image showing the forecast for the next week. This time of year places in northern Michigan would on average see highs in the upper 70s and lower 80s. Some of the highs early next week will feel more like early October! For folks that had a very cold winter, this is going to be a reminder the next one really isn’t that far away.