New weather station

My Davis is old and really in parlous condition (doesn’t like the 45

I installed the hardware and software yesterday.

Generally I’m quite impressed that a low-cost professional weather station performs so well. I have been able to give it a good test today, mainly because the weather has been so variable. At the same time, I’ve run my Davis system (with faulty wind data) in parallel, for comparison. For software, I’ve used Weather Display because a) I’m familiar with it; b) I can run it simultaneously on both the Davis and Aercus systems, to give direct comparisons. The test has run for 24 hours from about 17:11 yesterday.

I attach the 24-h data from both systems run simultaneously. To distinguish them easily, the Davis has the white background and the Aercus has the black background.

The results:

Wind speed and direction. As I had no data for comparison, I can only say that the result with the Aercus was very much as I expected.

Barometer. The results held within


Nicely done and a good result I think, aside from the predictable temp deviations.

Looking at the pic of the WS would i try to build a proper shield and probably add a fan for the temperature (like flowerplates + a comuter-fan like-a-thing).

Thanks! I’d already been thinking along both these lines, but Rome wasn’t built in a day!

Hi, have a look here, i have brill results from mine, My OS is on par with my Davis 24hr fars

http://discourse.weather-watch.com/t/61828

Able to do a better comparison on the rain gauges today with 10.8 mm (?) of rain. The old Davis one registered just over 1 mm less. I suspect that the Aercus was possibly more accurate, as it registered its first 0.3 mm jump at 01:21 while the Davis took until 01:54 (light rain) to register its first 0.2 mm jump. Thereafter the Davis jumps were more irregular. My guess is that there is stiction on the Davis see-saw. There are heavy showers forecast over the next 48 h and I’ll keep a keen eye on the two rain gauges.

I’m set up to put a better screen on the temp/humidity sensor of the Aercus after Easter but, as there has been little sun these past two days, the temp tracking between the two systems has been pretty good (

What diameter is the Aercus rain gauge?

It is more rectangular than round, perhaps about 160 x 70 mm with a sharp, bevelled lip. I’m not really enamoured of the design because, inside, it is quite shallow, perhaps only 25 mm deep around the periphery, and I’m pretty sure it could not cope with heavy 5 mm+ hail that we get from time-to-time. I also have reservations with driving rain in strong winds, without any proof that it cannot cope with it.

Aercus have a better rain gauge, which I would prefer, but I’m not sure if it can be incorporated into the weather station. It is less sensitive with a bucket tip of 0.45 mm, which surprises me (the rectangular one is 0.3 mm).

After a brilliant morning, it is now clouding over. My forecast is

[quote]Partly cloudy in the morning, becoming mostly sunny in the afternoon. Rain likely. Scattered thundershowers possible. High 22


Certainly not an obvious shape for a rain gauge, it will be interesting to see how it handles wind.

I have one of these stations here (WH3081)
the wind vane seized up

You mean that wind direction was in vain? :slight_smile:

I’d been mulling over the temperature difference between the Davis and the Aercus. I went to the local garden centre and bought 8 white plant saucers. First try was unsuccessful; too many saucers and not enough space for air to circulate. Reduced it to 5 saucers; still getting 3

Can we see a picture of the pagoda?

Good job :smiley: I use a lot of that aluminum tape, it’s the only tape that will stand up to the sun here. I know exactly what you mean by geometric incompatibility :lol:

OK, guys,

As requested, 3 photos of the semi-provisional installation (180 shows Davis in background). Telephoto has compressed the perspective; the distance from the Davis to the hedge is about 2


It’s demonstrated in testing that the Davis isn’t perfect (it’s a very simple screen after all) and solar radiation will have some effect on the measured temp so I think your hypothesis is most likely correct. A shaded Davis will be better than a Davis or any other simple/non-aspirated screen that’s in full sun. When the test conditions are different it’s difficult to make a meaningful comparison :dontknow:

Regardless, I think you have made a major improvement for the Aercus.

Thanks for the photos, an impressive improvement indeed.

Re temp and radiation, I always understood that it was difficult to measure air temperature at all without radiation playing a part, and that simple temp/hum sensors like ours would be better in the shade.

Even a Stevenson screen set-up is not perfect, it’s just an accepted standard enclosure that means the results should be reproducible and comparable.

I think we worry too much.

Correction: I think I worry too much. The result of a scientific background?

You are not alone!