Why Your Weather Station Needs Automatic Data Backup

Weather data has a quality that makes it different from most other digital information: it is irreplaceable. If you lose a photo, you might have another copy. If you lose a document, you can recreate it. But if you lose last year's rainfall totals, the highest wind gust of the season, or the temperature record from that heatwave, that data is gone forever. You cannot re-measure past weather.

Despite this, most personal weather station owners have no real backup strategy. Their entire history lives on a single SD card in a Raspberry Pi or in the limited retention window of the WeatherLink free plan. This post explains the risks and how to fix them.

Where your data lives today

The answer depends on how you run your station:

• WeatherLink free plan. Your current conditions are visible, but historical data is limited. Older observations roll off over time. If you rely solely on WeatherLink Basic, you do not have a long-term archive at all.
• WeatherLink Pro or Pro+. Your data is stored on Davis's servers, which is more reliable than a home setup. But you are paying extra for it, and it is tied to the WeatherLink ecosystem and its fixed interface.
• CumulusMX or WeeWX on a Raspberry Pi. Your data lives on the Pi's SD card or a USB drive. SD cards are notorious for corruption, especially under continuous write loads. If that card fails, your entire history can vanish.
• Manual backups. Some owners periodically copy their data directory to an external drive or cloud storage. This works but depends on remembering to do it, and most people forget until it is too late.

The backup gap

The core problem is that self-hosted setups rely on a single device with no automatic off-site backup. The device that collects the data is the same device that stores it, and the device that generates the website. That is three eggs in one basket.

Common failure scenarios:

• SD card corruption. The most common Raspberry Pi failure. Continuous logging wears out SD cards faster than typical desktop use.
• Power outage with filesystem damage. An unclean shutdown can corrupt the weather database.
• Fire, flood, or theft. If your home has an incident, the Pi goes with it.
• Quiet database corruption. Sometimes a database file becomes corrupted gradually. By the time you notice, the backups you do not have cannot help.

What proper backup looks like

A robust strategy for weather data has three properties:

1. Automatic. It runs without you thinking about it.
2. Off-site. It stores a copy somewhere other than your house.
3. Versioned. It keeps historical snapshots, not just the latest copy.

If you self-host, you can achieve this with a script that periodically copies your weather data to a cloud service like Backblaze B2, AWS S3, or a simple rsync to a remote server. But this is yet another thing to set up, test, and maintain.

The easiest solution: use a service that stores it for you

The simplest way to guarantee your weather history is safe is to use a hosted service that stores your data as part of its normal operation.

Pro Weather stores every reading from your station on the server side, indefinitely, as part of your subscription. There is no separate backup to configure. Your data is written to the database every 10 minutes and is replicated as part of the hosting infrastructure. If your house loses power, your Raspberry Pi fails, or your SD card corrupts, your complete history remains intact and accessible on your site.

This is what you are paying for when you subscribe: not just the website, but the assurance that your data is not going to disappear.

What you should do today

Look at where your weather data lives right now. If the answer is "on an SD card" or "only on the WeatherLink free plan," your history is at risk. The fix is either to set up automatic off-site backups or to move to a hosted service that handles it for you.

For a comparison of the options, see Best Weather Station Software for a Personal Website. If you want automatic data retention without managing backups, start your Pro Weather site and your data will be stored from day one.