Sometimes, in the world of amateur meteorology, it’s not the technology that trips you up. It’s the humble bin. Yes, a bog-standard plastic bin.
And not doing anything remotely interesting, just sitting there, quietly minding its own business. Or so I thought.
I always try to validate my data
Since I started logging daily weather readings here back in 2019, I’ve been comparing my figures to those from the good old Durham University Observatory.
It’s been my local benchmark – a trusted, well-sited station with solid heritage and a better postcode than me. Over time, I noticed something: my maximum temperatures were consistently coming in 0.5 to 1.0°C higher than theirs.
Not just once or twice. Pretty much every sunny day.
At first, I chalked it up to location quirks. Maybe the Observatory’s got a sneaky breeze I don’t. Maybe my garden’s a suntrap.
Maybe the weather gods just like me better. But the difference kept nagging at me. And then it hit me – what if the problem wasn’t the weather, but the setup?
Now, my thermometer is mounted on the north-facing wall of my shed, in permanent shade. That’s good. It’s what the guidebooks say.
But just 18 inches below it, right in the line of radiative fire, sat a plastic bin. And during the sunnier parts of the day, that bin, especially when it was a dark colour, would soak up the sunlight like a sunbathing seal, heat up like mad, and send all that lovely warmth straight up towards the sensor.
The bin was affecting the readings!
Even though the thermometer was in the shade, it was getting a subtle, consistent little nudge from below. A mini heatwave, courtesy of household waste management.
So this week, I finally did the sensible thing and moved the bin. Well, removed it entirely, to be honest. Took it round the corner where it can’t do any mischief. The sensor now sits at a nice, regulation-friendly 4ft above the ground. And here’s the important bit: it’s above concrete that’s permanently shaded.
No direct sunlight at any time of day. The most boring, reliable bit of ground I could find. Just how I like it.
What difference will it make?
Time will tell. But I’m expecting those max temperatures to behave themselves now.
That 0.5 to 1.0°C warm bias should flatten out, especially on calm sunny days where radiant heat plays a bigger role than wind.
The minimums probably won’t change much—the bin wasn’t giving off any warmth at 4am, but the daily range might narrow slightly. In short, my readings should now be much more in line with the Observatory’s, and probably closer to official Met Office sites too.
It’s one of those small tweaks that makes a big difference over time, especially if you care about accuracy (and let’s be honest, if you’re reading this, you probably do).
The lesson? Even a well-placed thermometer can be undone by everyday objects. Fences, bins, walls, compost heaps… they all have a say in the readings if you’re not careful.
If you notice a difference, this will be the reason
So, from today, if you notice that Durham Weather’s highs seem just a tad more conservative than usual, that’s why.
The sensor’s no longer getting a warm pat on the back from a sun-cooked bin.
Have you ever discovered a rogue influence messing with your home weather station? A misplaced BBQ? A gnome with a shiny hat? Let me know.
I’d love to hear your stories.