In this project, I will show you how to build a compact WiFi weather station with an OLED display.

The device connects to your local WiFi network, fetches real-time weather data and displays it on a small screen. It can be assembled as a clean enclosure build or as an open-wire minimal setup.

This guide covers wiring, firmware setup, configuration, and enclosure options.

No PCB is required — everything can be assembled using direct wiring.

How It Works

Operating Modes

The device has two modes, switched using a single button:

Indoor Mode:

Displays real-time temperature and humidity

Data is read directly from the SHT31 sensor

Outdoor Mode:

Connects to Wi-Fi

Downloads weather data from the met.no API

Uses coordinates defined in settings.h

Power Saving

The project is optimized for battery operation:

After 5 seconds — display brightness is reduced to 2%

After 20 seconds — device enters Deep Sleep

Wake-up occurs via button press

This allows long battery life even with a small Li-ion cell.

Weather API Information (met.no)

This project uses the official API of the Norwegian Meteorological Institute.

Key advantages:

Works worldwide

No API key required

High accuracy

Free and open access

Technical notes:

Europe and Scandinavia use high-resolution 1×1 km models

Global coverage is provided via ECMWF data

One of the most reliable public weather APIs available

Because of this, the project works anywhere in the world — just enter your coordinates.

Microcontroller: ESP32-C3 SuperMini

Display: 1.8" TFT (ST7735, 128×160)

Temperature & Humidity Sensor: SHT31 (I2C)

Button: 6×6 mm tactile switch

Power: 450 mAh Li-ion battery (e.g. from disposable vape)

Other: wires, solder, solder paste

Wiring

Solder everything according to the pinout.

Don't forget 3v3 and all GNDs

If you prefer a minimal aesthetic build, you can use thick solid-core wire and create a rigid “free-form” structure without enclosure.

Preparing the Firmware

Before uploading the firmware, you must edit the settings.h file.

1. Wi-Fi Configuration

Enter your Wi-Fi credentials:

constexpr char SSID[] = "your_wifi_name";

constexpr char PASSWORD[] = "your_password";

Without this, the device will not be able to retrieve weather data.

2. Location Settings

Set your geographic coordinates for accurate weather data:

constexpr double LATITUDE = 44.444444;

constexpr double LONGITUDE = 55.555555;

You can find your coordinates using Google Maps or any online GPS service.

Uploading the Firmware

1. Connect your ESP board via USB.
2. Select correct board in Arduino IDE.
3. Install required libraries (if needed).
4. Select correct COM port.
5. Click Upload.

After flashing, open Serial Monitor to confirm:

1. WiFi connection successful
2. Weather data received

If everything works, disconnect and proceed to final assembly

Enclosure Options

You can:

Option A – Print my enclosure

(STL files available in the project link)

Option B – Build your own enclosure

Option C – Keep it as an exposed “wire aesthetic” build

The device works in all configurations.

If you build your own version, feel free to share it.