My hikes typically start in a valley in the morning, where cold air has settled all night, and head uphill. If the valley’s fogged in I’ll hike from cool, moist valley air into sun-warmed hilltop air. I think the experts call these things thermal layers — and the implication is there’s a place where one layer ends and the next one starts.
Typically I’ll go from one layer to the other and not notice the cutoff, but yesterday something amazing happened: I was on a flat stretch of trail between two hilly sections and I noticed something odd: my head could feel hot air while my body could feel cold air. Always something new on the trail; this time it’s me hiking through two thermal layers at the same time.
As long as I’m on the subject of temperatures … last weekend I was about three miles into my hike at Henry Coe State Park when I crossed a stream after descending an excessively steep gravel road. The road’s incline was nasty enough that I had worked up a pretty good sweat. As soon as I stepped out of the water it felt like my body’s temperature-regulation system had just been rebooted. Where before I was dry and bordering on uncomfortably warm, now I had squishy wet feet but the rest of me seemed like all its default settings had been restored. I felt comfortable and normal, which came as a distinct surprise, considering I was carrying 20 pounds of gear and had just hiked three miles. I’ve always liked stomping through puddles; now I’ve got a permanent excuse for indulging the urge.
One last temperature note: it appears we’ve seen the last of the cool, damp, rainy weather around the Bay Area. won’t be long till we’re all complaining about how hot it is on the hills.
Microclimates are fascinating phenomenon. One time camping at the Curch Creek Divide site in the Ventana Wilderness, a fellow camper was cold and damp all night while I was warm and dry. I just 8 ft. higher (in elevation) than him, and about 30 ft. away.
Used to travel down through an inversion layer daily on my way to work. Never could tell what the weather was going to be like, I would often leave a cloudless, sunny, 75 degree day and end up in a foggy, rainy, 45 degree day. – But isn’t that the way going to work is supposed too be?
Learned about cooling the body by wetting the feet years ago while I was down south and working outside during the summer. We used to ask people if we could borrow their hose for a moment, and then the crew would stand around it and rinse their feet. It’s the best way for refreshing the body other than a cool shower, and you can do it in public.
I take advantage of any ditches, creeks, or ponds while hiking.