Since the topic of which season is best for seasoning wood comes up often, I decided to follow the humidity the last few days. The humidity the weather folks give is the relative humidity, which measures how much water vapor the air is holding relative to how much it could hold. The warmer the air, the more water vapor it can hold. The last couple of days has been hot- mid to upper 90’s. While it feels humid in the middle of the day, the high temperatures give the air the ability to hold a lot of water vapor. If anyone told me today the humidity was actually low, I would have argued till I was blue in the face but here are the numbers. The real value to look at is the dew point. The bigger the gap between temperature and dew point, the drier the air is and more evaporation will take place. So I will take summer seasoning over winter seasoning.
I was thinking about this myself not too long ago. You think summer heat must be great for drying out wood. But then there’s the humidity factor. So maybe winter is also useful because it’s so dry it must suck the moisture right out of the splits. Might be a little truth in both. Whether it dries more in the heat or more in the cold, I don’t know. Most of what I have on hand was split before the heat set in and is looking great so far, so I’d say I’m a believer in the heat argument.
But that’s my point. It may feel humid because hot air can hold a lot of water when in reality, many afternoons in the summer the relative humidity is far lower than we think and evaporation rates are very high.
When the Rh is 100% and the temp is 75º and the dew point is 75º wet beach towels don't dry on the clothesline outside. Fortunately we don'[t have a lot of those days, but we have enough of them. The dryer days make up for them. We have had enough of them though that the front door stays swollen and is tough to open and close. I'm not shaving a 1/16 off as the gaskets work perfect in the Winter keeping the cold dry air at bay. A distinct advantage to fiberglass doors (as long as the door frame behaves).
Maybe FHC can send you all expense paid to Siberia this Winter so you can do some research Joe! Although it did have record heat there recently. Saw on TWC this morning the great Lakes have record warm water...waaaaay above average too by several degrees.
Naturaly wood and other things will dry quicker in warm to hot weather and we can see it even without any fancy instruments. Common sense can still tell most of us a lot.
I’m not too far from you so our conditions aren’t very far apart. But being in the mountainous region seems to elevate humidity. We’ve had a couple days recently that were brutal. And the forecast this week is hot. Kiln dried lumber is done with heat so I’d venture to say the science is there to support your claim.
It would be interesting to see if the hours of daylight in the summer and winter were the same, but the temperature and humidity were the differences, which would dry quicker. As said by others, it should be obvious that long sunny days with more sun, higher temps, and no snow covering the piles will dry quicker than in the winter. Put a damp cloth on your driveway in the sun, and another in the shade of a garage and see which one dries out quicker.
Check out humidity levels in the middle of those hot days. You’d be surprised just how many “humid” days when it’s that hot are below 50%. I was shocked to see it under 30% yesterday because you’re soaked with sweat as soon as you go outside
I am an advocate of, wherever water is, it wants to be someplace else, except where there is more water. Water will move towards a drier, less moist location, considering gravity. Given circulation around my wood stacks, the drier the air, the better the drying impact. Except, when the temps are below freezing. Even then, the process called sublimation, allows ice to evaporate. So, lower temps,40's, and a dew point in the 30's should season wood better than temps in the 90's, with a dew point of 75. The drier the air, the higher the potential is of water moving out of wood. But, what do I know.
Hmmmm.... If the outside temp was 45 F and the dew point was 35, the relative humidity would be about 68% If the outside temp was 95 F and the dew point was 75, the relative humidity would be about 53% So you're saying more humid air seasons wood better?