OpenWeatherMap library for Espressif microcontrollers and Arduino IDE/PlatformIO

OWM_for_ESP is a simple and optimized library to work with OpenWeatherMap. It works with several types of APIs: Current (current weather only) and One Call (weather with forecast).

To use it, you also need to download the JSON parsing library: https://github.com/Bodmer/JSON_Decoder.

Support for the library has been discontinued 😞

This is due to the discontinuation of One Call API 2.5 due to the release of One Call API 3.0. The new policy requires adding a bank card, which is impossible due to sanctions on the Russian banking system. I will not be able to test the changes in the library.

Also, Roskomnadzor (government prohibitions) has started to enable blocking of https connection to OpenWeatherMap at random times few years ago, so getting weather in Russia is becoming unstable.

If you are in Russia, you probably need to consider analogues of this service (or use Current weather only). If you live in another country, you can implement changes yourself to move to One Call API 3.0.

Thank you for using the library. Its development will continue in a few years: besides API improvements, I'm going to deliver my weather station code in Examples folder (it will be completely rewritten to move to ESP32-C3 and add new features (e.g. English language handling)), after which the library will be added to PlatformIO Registry. The new library will be here.

Secure connection

This library supports secure connection using HTTPS, which is enabled by default.

Since ESPs don't have hardware cryptography, it takes 2.5-3.5 times longer. If you are not worried about security, you can enable the unsecured connection mode.

Library usage

With the User_Setup.h file you can change language of condition info, connection type (unsecured HTTP or secured HTTPS), number of minutes and hours (for One Call), exclude strings with description from API (it can be got with getStatus), setup logging parameters.

Available methods:

• .getWeather(*current, *hourly, *daily, latitude, longitude, type) takes OWM_current, OWM_hourly and OWM_daily variables, user latitude and longitude, API type, which is used to form the request. It adds all received data to the structures from which you can easily retrieve the necessary data later.

• .getCurrentWeather(*current, latitude, longitude) similar to .getWeather(*current, nullptr, nullptr, latitude, longitude, CURRENT).

• .getFullWeather(*current, *hourly, *daily, latitude, longitude) similar to .getWeathergetFullWeather(*current, *hourly, *daily, latitude, longitude, FULL).

• .setApiKey(apiKey) saves your key for future weather retrieval.

• .setUnits(units) saves the preferred type of units.

• .getIconCode(iconId, begin, end) is used to get the code of an icon from its internal library ID. This method was added to save RAM.

• .getShortStatus(id) is used to get a simplified description of the weather from its official ID. This method was added to save RAM and to easily edit states if the official ones don't satisfy you.

• .getStatus(id) is used to get a full description of the weather from its official ID. This method was added to save RAM and to easily edit states if the official ones don't satisfy you.

• .getStatus16(id) similar to .getStatus(id), but outputs shortened states to 16 characters especially for displays.

You can also check the example OWM_for_ESP_Test.ino.

Weather receiving speed comparison in milliseconds

Tested with PlatformIO Espressif 32 platform v5.3.0, max CPU and flash speed, secure connection, no strings.

Current

Board	Connection	Header	JSON parsing	Full receieve time
ESP8266	2163	157	11	2331
ESP32	1217	222	14	1453
ESP32-C3	1056	207	11	1274
ESP32-S2	1060	160	15	1235

Full (One Call): current, hourly (48 hours), daily (8 days)

Board	Connection	Header	JSON parsing	Full receieve time
ESP8266	2298	1842	365	4505
ESP32	1205	844	333	2382
ESP32-C3	1157	752	295	2206
ESP32-S2	1139	489	588	2217

Full (One Call): current, without hourly, daily (8 days)

Board	Connection	Header	JSON parsing	Full receieve time
ESP8266	2300	738	90	3128
ESP32	1225	373	89	1687
ESP32-C3	1157	272	75	1505
ESP32-S2	1119	183	143	1446

Projects with this library

• mxkmn/esp8266_weather_station // Weather station using esp8266, lcd1602 display, two buttons for navigation, able to show the weather forecast for the next week and 48 hours, fully prepared for changes to another type of display or navigation. At the moment it is exclusively in Russian, but can be translated into any other language.

If you have published a new project using OWM_for_ESP - put a link in Issues marked new project, write some info and I will add it to the project list.