# Import Your WeeWX History Into Pro Weather

URL: https://pro-weather.com/blog/import-weewx-history

> Pro Weather now imports your WeeWX archive - years of records, parsed from weewx.sdb in your browser, in every weewx unit system, safe to re-run, nothing uploaded.

The most common reason people gave for not moving off a self-hosted WeeWX box was never the software. It was the archive: five, ten, fifteen years of five-minute records that a fresh start would abandon. That reason is now gone. Pro Weather imports your WeeWX database directly, and your whole history lands in the charts, the records page and the almanac as if it had been collected here all along.

**Key takeaways:**

- Pro Weather reads your `weewx.sdb` and imports the full archive: temperature, wind, rain, pressure, solar, UV, indoor and air-quality readings included.
- The database is parsed in your browser, not uploaded: only the observation values travel, so a multi-hundred-megabyte file never leaves your machine.
- All three weewx unit systems (US, METRIC, METRICWX) convert automatically, and even a database that mixes them imports correctly.
- The import never overwrites live data and skips anything already archived, so re-running it, even after an interruption, is always safe.
- Old databases still on the classic wview schema work fine; whatever columns exist are imported.

*Looking for the short version? The step-by-step lives in the help center: [import your weewx history](https://pro-weather.com/docs/getting-started/import-weewx).*

## What gets imported?

Everything Pro Weather archives that WeeWX also stores. In practice that is the whole picture your charts and records are built from:

| Category | Readings |
|---|---|
| Temperature | Outdoor temp, dew point, heat index, wind chill |
| Humidity | Outdoor and indoor humidity |
| Pressure | Barometer (sea level) and station pressure |
| Wind | Speed, gust, both directions, wind run |
| Rain | Per-interval rainfall and rain rate |
| Sun | Solar radiation, UV index, evapotranspiration |
| Indoor | Console temperature and humidity |
| Air quality | PM1, PM2.5 and PM10 where a sensor recorded them |

Once imported, the history behaves exactly like natively collected data. It feeds the historical charts, the all-time and monthly records, the almanac, and the [automatic backups](https://pro-weather.com/blog/weather-station-automatic-data-backup) that come with every site.

## Your database never leaves your machine

This is the part worth pausing on. A WeeWX archive that has been running for a decade is easily hundreds of megabytes, and most of that bulk is day-summary bookkeeping no import needs. Uploading a file like that to a server, having something parse it there, and trusting the service with the whole database is the obvious design, and it is not the one we picked.

Instead, the import page opens your database locally. **sql.js** is the SQLite database engine compiled to WebAssembly, which means a web page can open a real database file entirely inside your browser, with no server involved. Your browser reads the archive table and sends only the observation values, a few thousand records at a time. The file itself is never transmitted. You can watch the progress bar tick through a multi-year archive in a few minutes over an ordinary connection, because what actually travels is a small fraction of the file's size.

## How do I run the import?

1. Copy the database off the machine running WeeWX. **weewx.sdb** is the SQLite file where WeeWX keeps its entire archive; on a standard install it lives at `/var/lib/weewx/weewx.sdb`, so something like `scp pi@raspberrypi:/var/lib/weewx/weewx.sdb .` does it.
2. Open your site's **Connection** tab in the Pro Weather dashboard and find **Import history from weewx**.
3. Pick the file, choose which station the history belongs to if your site has more than one, and click **Import history**.
4. Leave the tab open until the progress bar completes. Charts and records pick up the new history within a few minutes.

History is part of the PRO plan, so you need an active subscription or trial; the [pricing is on the homepage](https://pro-weather.com/#pricing) and the trial is long enough to import first and decide afterwards.

## Which WeeWX databases work?

**Any SQLite archive, on any schema vintage.** WeeWX has shipped two archive schemas over the years: the classic wview schema and the extended one that added air-quality and lightning columns. The importer checks which columns your database actually has and takes what exists, so a database created in 2012 imports as happily as one created last month.

**Any unit system.** **usUnits** is the field WeeWX writes into every archive record to say which unit system that record uses: US (degrees Fahrenheit, inches), METRIC (Celsius, cm of rain, km/h wind) or METRICWX (Celsius, mm of rain, m/s wind). The import converts each row by what that row says it is, so all three systems work. So does a database that changed systems halfway through its life, which really happens to long-running installs migrated between machines.

**MySQL needs one extra step.** The importer reads SQLite files. If your WeeWX runs on MySQL or MariaDB, transfer the archive to SQLite first with WeeWX's own tool (`weectl database transfer` with a SQLite destination binding, covered in the [WeeWX documentation](https://weewx.com/docs/)), then import the resulting file.

## What happens where histories overlap?

Nothing destructive, ever. The import follows one rule: **records that already exist win**. Rows the archive has and Pro Weather lacks are added; rows both have are left alone.

A worked example. Say you connected your station to Pro Weather on 1 May and your WeeWX archive runs from March 2016 to today. The import adds March 2016 through April of this year untouched, and everything from 1 May onward - the period both histories cover - keeps the live version Pro Weather recorded itself. Your rainfall totals stay right because no interval is ever counted twice.

The same rule is what makes re-running safe. If your laptop sleeps mid-import or the connection drops, just run it again: everything already imported is skipped at full speed and the import continues where it left off. There is no cleanup step and no way to end up with doubled rainfall totals.

## Keep WeeWX running, or retire the box?

Either works, and the choice is genuinely yours.

Plenty of people keep WeeWX archiving locally as a second copy and point its Weather Underground uploader at their Pro Weather upload URL, so live data continues seamlessly from the moment the import ends. The [connect your own hardware](https://pro-weather.com/docs/getting-started/connect-hardware) guide has the three-line config change. Run both and the two archives simply grow in parallel, which is the setup we compare honestly in [Pro Weather vs WeeWX](https://pro-weather.com/blog/pro-weather-vs-weewx).

If the WeeWX box was the last thing keeping a Raspberry Pi, a UPS and an SD-card backup ritual alive, you can also just switch it off. The history it guarded is now hosted, backed up and public. What that box really cost to keep running is a story of its own: see [the hidden costs of running a weather server](https://pro-weather.com/blog/hidden-costs-running-weather-server), and the wider landscape of [weather station software](https://pro-weather.com/weather-station-software) if you are still weighing options.

## Common questions

**Does the import change my WeeWX database?**

No. The file is opened read-only in your browser and never modified, never uploaded. Your local archive is exactly as it was.

**How long does it take?**

A few minutes for most archives. The work scales with the number of records rather than the file size, and a decade of five-minute data is around a million records sent in batches of a few thousand.

**Will my imported history show in the records and almanac?**

Yes. Records, monthly summaries and the almanac are computed from the same archive the charts read, so a cold morning in 2015 can hold the all-time low on your site the moment the import finishes.

**My station is not the one WeeWX was reading. Does that matter?**

The import asks which of your site's stations the history belongs to, and the sensible default is the local (push) station that receives your hardware's uploads. If you replaced the hardware itself along the way, the history is still yours; import it to the station that represents that location.

**CumulusMX, not WeeWX?**

The importer reads WeeWX SQLite databases today. If you are choosing between the two self-hosted options first, [CumulusMX vs WeeWX](https://pro-weather.com/blog/cumulusmx-vs-weewx) is the comparison; if you already have a CumulusMX archive you want to bring over, tell us - it helps us order what to build next.