Build an Arduino Weather Station: Track Temperature, Humidity, and More

If you enjoy Arduino projects and love watching the weather, building your own Arduino weather station is a perfect weekend build. Instead of relying on generic weather apps, you can collect data from your exact location—your backyard, balcony, or shed roof—and feed it into dashboards, spreadsheets, or even your homelab.

This guide walks through the core components, wiring, and code needed to measure temperature, humidity, and air pressure, with ideas for expanding the system later.

Arduino prototyping on a desk — Typical Arduino breadboard prototyping setup

Core Components for a DIY Arduino Weather Station

You don’t need exotic hardware to get started. A common beginner‑friendly parts list includes:

Arduino Uno or Nano – Reliable, well‑documented microcontroller board.
Temperature/Humidity Sensor – DHT22 or similar digital sensor.
Barometric Pressure Sensor – BME280 or BMP280 module.
Breadboard and Jumper Wires – For easy prototyping and rearranging.
USB Cable – To upload code and power the Arduino.

Optional extras:

LCD or OLED display to show live readings on the device.
Enclosure to protect the electronics outdoors.
ESP8266/ESP32 if you want Wi‑Fi connectivity instead of USB.

Wiring the Sensors to the Arduino

Most modern weather sensors use simple digital interfaces like I²C or a single‑wire protocol.

Example: Connecting a DHT22 and BME280

Connect sensor VCC to Arduino 5V (or 3.3V if required).
Connect sensor GND to Arduino GND.
For DHT22:
- Data pin → Arduino digital pin (e.g., D2) with a suitable pull‑up resistor if needed.
For BME280 (I²C mode):
- SDA → Arduino A4 (on Uno)
- SCL → Arduino A5 (on Uno)

Double‑check the pinout diagrams for your specific sensor modules—some breakout boards rearrange pins or operate only at 3.3V.

Example Arduino Sketch for Weather Data

Once everything is wired, you can upload a simple sketch that:

Reads temperature and humidity from the DHT22.
Reads pressure and temperature from the BME280.
Prints the values to the serial monitor (and optionally to an attached display).

You’ll need to install any required libraries via the Arduino IDE’s Library Manager (for example, Adafruit BME280 and DHT sensor library).

Logging and Visualising Your Weather Data

Collecting numbers is fun, but visuals are better. A few ideas:

Send serial data to a Raspberry Pi and log it into a database.
Use MQTT with an ESP8266/ESP32 version of the project to publish readings to your homelab.
Visualise measurements in tools like Grafana, Home Assistant dashboards, or custom web pages.

Over time you can compare your DIY readings with official weather stations and spot local microclimates in your own backyard.

Weatherproofing and Outdoor Placement

Electronics and weather don’t mix—unless you plan ahead:

Use a radiation shield or Stevenson‑screen style housing for your sensors so sunlight doesn’t skew temperatures.
Protect the Arduino and wiring in a weatherproof enclosure with cable glands.
Mount sensors away from direct heat sources, air‑conditioning exhausts, or reflective surfaces.

Proper placement is critical for accurate readings; a sensor stuck on a hot brick wall will report wildly unrealistic temperatures on sunny days.

Expanding Your Arduino Weather Station

Once the basics are running reliably, consider adding:

Rain gauge using a tipping‑bucket sensor.
Wind speed and direction with an anemometer and wind vane.
Light intensity sensors to track daylight and solar potential.

Each additional sensor opens the door to more advanced projects—like automating irrigation, controlling shade systems, or feeding data into renewable energy planning.

Arduino Weather Station Build Checklist

Gather your Arduino board, sensors, and basic wiring tools.
Wire DHT22/BME280 (or equivalents) to your chosen pins.
Install the necessary libraries in the Arduino IDE.
Upload a test sketch and confirm values in the serial monitor.
Weatherproof the installation and mount sensors outdoors.
Start logging and visualising your new local weather data.

With a weekend of tinkering, you’ll have a DIY Arduino weather station that not only teaches you more about electronics and coding, but also turns your home into a mini observatory for the changing climate around you.