Professional weather at home
Update, 25 October 2026: the Kerroch house has been sold. The station stayed where it was, with the buyer, and I disconnected it from every site, public and private. The links to live data no longer respond, and this article has become the record of what ran for three years. Throughout that whole period, publishing to Wunderground, PWS Weather, Awekas, WoW and Météo Bretagne worked without a single interruption.
I’ve become passionate over the past few years about weather observation. I chose the Vantage Pro 2 from Davis Instruments, known for its reliability. I chose to install it on my flat roof deck for convenience (very easy to access, with no nearby obstacles). I expanded the setup by adding UV and solar radiation sensors, then an Airlink module (also from Davis Instruments) to measure air quality (PM1, PM2.5 and PM10, plus US AQI and NowCast). All observations were uploaded by a Weatherlink Live module, and towards the end by the new Weatherlink console, to Davis Instruments’ Weatherlink site.
In 2024 I set up a Raspberry Pi 4 running Weewx5, later upgraded to Weewx 5.1. I reused the old Davis console and its data logger to capture every weather and air-quality observation locally on the Pi 4, which made me independent of the Davis cloud. That real-time data was published on a dedicated page. The station sent its readings roughly every 2.5 seconds. I chose the Belchertown skin for presenting the data and the weewx/airlink extension for folding in the air-quality readings.
On the hardware side, the Raspberry Pi 4 (4 GB of RAM) sat in an Argon ONE M.2 case, with a 130 GB SATA SSD over USB rather than an SD card — more reliable over time. It ran in my garage, next to the old console, 40 to 50 m from the ISS out on the terrace: I never lost data on the Raspberry side, unlike the kitchen console, which sometimes struggled with the concrete slab. After two years of continuous operation, usage stayed very modest: about 500 MB of RAM out of the 4 GB available, 5% CPU at most, and an SQLite database growing by around 160 MB a year (15 MB at the start, 157 MB after a year) — enough to last several decades. On budget: around €54 for the Raspberry Pi 4 (model B, 4 GB) and €45 for the Argon ONE M.2 case, a modest investment. And on the database safety margin: SQLite can in theory take 400,000 to 500,000 HTTP requests a day and grow to 281 TB, so at 160 MB a year there is nothing to worry about in a lifetime.
Besides the Belchertown skin and the weewx/airlink extension, I also tried the Envoy extension to cross-reference my weather data with the output of my Enphase solar system, without success — the database would not update, and I never worked out whether the problem was my installation or an extension that is barely maintained any more. I won’t have had the time to get to the bottom of it.
The installation itself is fairly simple, though it takes some care: flash 64-bit Raspberry Pi OS onto an SD card, run the system updates, enable VNC and force the boot order to USB, then clone the SD card onto the SSD before booting from it for good — far more reliable than an SD card over time. Then install Nginx for the web server, then WeeWX via its official installation script, entering the station’s name, coordinates and altitude. The only real sticking point: the weewx user had no access to the console’s USB serial port (/dev/ttyUSB0) — it had to be added to the system’s dialout group before collection would start.
The Belchertown skin, developed by Pat O’Brien, is installed with the weectl extension install command pointing straight at the archive in the GitHub repository (the syntax changed from older Weewx versions, which used wee_extension --install). Once installed, the Weewx service has to be restarted for the report to be generated — it is added alongside the standard “Seasons” report without replacing it, in a belchertown subfolder — then the Nginx configuration has to point at that subfolder and the web server be restarted. The result was a good deal more polished: noticeably larger charts, a Windy radar widget positioned automatically from the station’s GPS coordinates, a dark mode, an “About” page. Belchertown can also show forecasts via the Aeris API, provided you have a PWS Weather account and obtain a key after a few days of publishing — an option I never enabled. I had meant to look into the architecture Pat O’Brien uses on his own site: an MQTT broker synchronising data between his Raspberry Pi and his external hosting, which would have allowed a genuine real-time weather page rather than a static description. I won’t have had the chance.
Weewx5 also let me publish the Kerroch weather observations to the well-known weather sites: Wunderground, PWS Weather, Awekas, WoW and, latterly, the site of the Météo Bretagne association (run by Meteo Concept). These sites also push the data through iOS and Android apps. All of it worked without a hitch for three years. It was all driven from the weewx.conf configuration file: each service has its own section, with a simple Enable = True and the credentials of the account created on that site — Weewx then takes care of sending the data itself. My station also appeared on the Weewx station map (weewx.com), which lists around 1,900 stations worldwide; there are rather few in Brittany, and Vantage Pros are rare. Of all these sites, my two favourites remained Wunderground — which awards a confidence level that rises the longer a station publishes without a break, and I was at the maximum — and PWS Weather, both with a careful and complete presentation. Awekas and the Met Office site (WOW) worked well too, but with an interface I found more confusing.
The village of Kerroch sits by the sea in the commune of Ploemeur. Through all those years, the Vantage Pro withstood the salt spray, the storms and the gales.
For a general presentation of the hardware and the full installation story (on video), see Presenting and installing my Vantage Pro 2 weather station.
History:
- April 2022: installation of the Davis Instruments Vantage Pro 2 and the AirLink module for air quality.
- July 2022: UV sensor added.
- February 2023: solar sensor added for radiation measurement (W/m²).
- February 2024: live data and charts published from Weewx and the Belchertown skin.
- March 2024: air-quality data added with the weewx/airlink extension.
- Summer 2026: the house is sold, the station stays behind and stops publishing.
Village of Kerroch — commune of Ploemeur — Morbihan. The little harbour and its fine sandy beach.
Monthly reports and compressed archives for past years:
//2024// January, February, March, April, May, June, July, August, September, October