This was the first week it dropped into the thirties overnight. The trees are turning. The air is brisk enough now that morning coffee on the porch requires a blanket or a heavier coat. The animals know before I do. They bunch up differently in the morning; they are slower to come out, and they stand in the sun now instead of the shade. A thin layer of ice is starting to form across the top of the water buckets. And the flies and mosquitoes are finally dying off. The mosquitoes especially. A wetter monsoon season than normal this year meant standing water everywhere, which meant more of them than we have dealt with in a while. It feels overdue. I will take this over a Tucson summer every time. I would much rather warm myself up than cool myself down. We brought the vertical electric heaters out this week. Each one is on a different circuit, which matters more than people think. A space heater pulls about 1,500 watts, and two of them on the same 15-amp circuit is most of what that circuit can carry before anything else is running. Wood is split and stacked, so the stove is ready when we want it. First fire of the year is still an event around here. What is the first sign of fall where you are?

Heating season is here, and a lot of us are building a wood pile right now. Most of us learned this by watching somebody else do it. No instruction, no explanation of why anything is done the way it is done, just a general sense of how it goes. That works until it does not. People put axes into their shins and their feet every year, and nearly all of it traces back to two or three things nobody ever told them. Here is what actually matters. Two terms before we start. A round is a section of tree trunk cut to firewood length, standing on end. That is what you split. A chopping block is what you stand it on. - Start with your chopping block A chopping block is a short, wide section of log that you stand the wood on while you split it. It is the most important piece of safety equipment you will use, and most of what goes wrong comes down to not having one or using the wrong one. Block height is the single most important number in this post. Twelve to sixteen inches, which puts it at or just below knee height for most adults. University of Wisconsin Extension gives the rule cleanly: cut your block so the angle between the round and your maul is ninety degrees at the moment of impact. Here is why the height matters more than anything else. A block at the correct height means a missed strike buries the head in the block. A block that is too tall, or no block at all, means a miss carries the head past the round and down toward your shins and feet. You will miss. Everybody does. The block is what decides where the miss lands. Make it wide and stable. The knottiest, ugliest round you have makes the best block, because it resists splitting. Set it on firm ground with no give. If it wobbles, shim it or dig it in. ***Never split on concrete. A maul can shatter it, and it can bounce off unpredictably. - If you have no block at all A downed horizontal log works, laid flat on the ground. Set your piece on top of it and split down into it. Check for overhang first. If the piece you are splitting hangs off the edge of the log underneath, the overhanging part flies back at you when it breaks. Full contact or do not do it.

One of my first monsoon seasons on the fire department in Tucson, a storm came through and took down a cascade of power lines across Grant Road. Not one line. A run of them, draped over multiple vehicles with people inside. We were on scene for two to three hours before the power company confirmed the lines were de-energized and we could start helping people out of their cars. Two to three hours. A full crew standing there, and the only correct thing for those drivers to do was sit still and wait. So here is this week's question. - What if a power line came down on your vehicle while you were in it? Talk it through tonight: Do you get out? Ask everybody separately and see what they say. How far away is far enough? What do you tell somebody who walks up to help? What if the vehicle catches fire? What does your teenager do, driving home from practice, when a line is down across the road? - Your first instinct will be to get out of the vehicle, and that is the thing that kills people. You stay in the vehicle. Here is why, and once you understand the why, the rest of it stops being rules to memorize. - Step potential When a live line touches the ground, the electricity does not stay at that one spot. It spreads outward through the earth in rings, like ripples in a pond. The voltage is highest at the contact point and drops as it moves out. Which means the ground around a downed line is at different voltages depending on where you are standing. Take a normal step and your two feet land in two different voltage zones. Current takes the easy path between them, which is up one leg and down the other, through your body. You do not have to touch anything. The ground does it. That is called step potential, and it is the reason for everything below. - The 35 foot rule Stay at least 35 feet from a downed line and anything it is touching. About the length of a school bus. Utilities vary a little on the number. PG&E says 30 feet on dry ground and 60 feet on wet ground, which is worth knowing because water makes the energized area considerably larger.

Monday, I had you walking the house, touching outlets and looking for warm faceplates. That works, and it has an obvious limitation. You can only find what you can reach, and most electrical problems happen inside a wall where nobody is looking. There is a device that watches the whole house from one outlet. - What it is Ting, made by a company called Whisker Labs. It is a small sensor that plugs into any standard outlet. You download an app, it connects to your wifi, and it takes about two minutes to set up. Most homes need exactly one. It monitors the entire electrical system from that single outlet, because it is reading the electrical signal across the whole house rather than just that circuit. The exception is a home with more than one main panel, which needs one per panel. Why one sensor covers the house: your wiring is all electrically connected, and arcing produces a high-frequency signature that travels through the system. Ting is not monitoring the outlet it is plugged into. It is monitoring the electrical network that outlet is part of. The exception is a second main panel. A subpanel fed from your main is covered. A detached shop, barn, or well house on its own separate service from the utility is not, and would need its own sensor. - What it actually detects Micro-arcing. This connects directly to what we covered Monday. Arcing is the small repeated sparking that happens at a loose connection, a damaged cord, a worn receptacle, or a nail driven through a wire. It generates serious heat, and it is a leading cause of electrical fires. A standard breaker will not catch it because the current draw looks normal. Ting takes thousands of readings per second, looking for the electrical signature of arcing somewhere in the house. When it finds a pattern that matters, it alerts you. It also monitors the power coming in from the utility, which means it catches problems on the pole or at the meter, not just inside your walls.