Monday morning I was awake earlier than usual and the first thing I noticed when I opened the door was how cool it felt, like late September slipped in overnight.

I felt light, energized, alive, and ready to go. I was so energized that before 7 a.m., I was dressed, finished with feeding animals, had my bed made, put a load of laundry in the washer, had had a breakfast smoothie and was outside doing yard work.

For the rest of the morning, I was a doing machine. I cleaned the dogs’ bowls, trimmed limbs and untangled a vine wrapped around one of my roses. Oh, I was as happy as my daylilies dancing in the fall-like breeze.

Inside, I vacuumed, cleaned my bathroom, put clothes in the dryer and dusted everything in sight. All the while, cool air slipped in through the screen door. It was heaven.

Mid morning, I took a break and, surrounded by cats, sipped a second cup of coffee sitting by the water. I could almost imagine it was a fall day as I watched a heron fly across the lake.

For the rest of Monday, I moved with purpose. I changed sheets on my daughter’s bed, folded clothes and prepared for my evening yoga class. It was a productive Monday.

By nightfall, the humidity came creeping back. Sitting out on the back deck was not comfortable so my husband and I escaped inside to the air conditioning.

Tuesday morning, I struggled to get out of bed at the usual time. The morning air hit me in a hot, humid rush when I opened the door. I felt heavy as a rock and drug through feeding time, getting the bed made and putting on my clothes.

“What the heck happened?” I said to the face in the bathroom mirror. “Where did that light, happy, yesterday energy go?”

That made me wonder if the weather had anything to do with feeling so draggy. Turns out that might be the case.

According to a 1980s study, humid weather increases tiredness while low humidity makes people feel more pleasant. According to the study, humidity does three things.

First, it makes you forgetful. So, that’s why I couldn’t remember where I put the phone.

It makes you lethargic. Explains my reluctance to vacuum Tuesday. Finally, and surprisingly, humidity makes people less anxious. Experts concluded this is because you are tired and “it’s hard to be nervous when you’re busy napping.”

The study also said something about sweating not working as well when it’s humid because the body works harder to stay cool, which is also tiring. Well, sweating might not work as well, but stinking to high heaven from the body trying to cool itself is in perfect working order when it’s humid. Trust me on this one.

(Don’t even get me started on what humidity does to your hair. And hot flashes — studies say humidity makes those worse. Well, ah yes, it does, but that’s another column.)

Yet another study found “… mood was higher when humidity was low.” Well, if that’s true, look out for some low moods around these parts for the next three months or so. (However, my observation concludes this study does not take into account how moods improve with the start of college football season in Alabama no matter how much humidity is in the air.)

Finally, a study conducted by Columbia University concluded “… human moods and productivity appear to be affected by the weather …”

So, until another blast of September cool shows up, I just may be a lethargic, forgetful, less anxious (a.k.a napping), flat-haired, hot-flashing, stinkier human.

Happy Southern summer, ya’ll.