Privacy
Thermograph is free, has no ads, and needs no account. It is built so that there is very little about you to collect in the first place.
Your location
{# This section states a fact about what the server actually does, so it follows the THERMOGRAPH_GEOIP flag instead of being written once and left to rot. See content.py's geoip_enabled(). #} {% if geoip %}The precise way the site learns where you are is if you press Use my location, which asks your browser for permission. You can decline, and picking a place on the map works just as well.
If you decline, or your browser cannot offer it, we fall back to a rough guess at your city from your IP address so there is something local to show instead of nothing. It is always labelled as a guess, never as your position — it is accurate to tens of kilometres at best, and one tap corrects it. It is also not remembered: a guess is never saved in your browser or written into the page address, so only a place you actually pick is kept.
That lookup runs entirely on our own server, against a database file we host ourselves. Your IP address is never sent to another company, and it is not stored: it is read from the request, used to find a city, and discarded. It is deliberately kept out of our request log for this feature too, so nothing anywhere links an address to a place.
{% else %}Thermograph never looks up your location from your IP address. The only way the site learns where you are is if you press Use my location, which asks your browser for permission. You can decline, and picking a place on the map works just as well.
{% endif %}Whichever way you choose a place, the coordinates are sent to the server only as part of the ordinary request for that grid square's climate data, and are not logged beyond the normal web-server request handling every site does. The place you picked is remembered in your own browser's local storage, not on the server, so clearing your browser data forgets it.
Analytics
There is no analytics library, no cookies for tracking, and no per-visitor identifier. The server keeps simple aggregate counts (how many people opened a page or tapped a button, and which site referred them) with nothing tying any of it to an individual.
If you sign up for the monthly digest, your address is used for that digest and nothing else. It is never sold or shared, and every message can unsubscribe you.
Accounts
An account is optional and only exists to hold weather alerts you have asked for. It stores your email address and the places you are watching.
Questions: see About & methodology.