How to Build a DIY IoT Weather Station with Arduino in 10 Minutes

Building your own IoT weather station with Arduino is an enjoyable weekend project that can teach you a lot about electronics and coding. With just a handful of inexpensive components, I was able to assemble a fully-functional weather monitor in under 2 hours. Here is a step-by-step guide on how I built my own DIY IoT weather station using an Arduino Uno.

Shopping List

Here are the components I used for this project:

The total cost was around $50. The DHT sensor and rain sensor provide temperature, humidity and rainfall data. The anemometer measures wind speed. All the sensors connect to the Arduino board, which uploads the data to the cloud via the WiFi module. The LCD display shows the current readings on the device itself.

Step 1: Connect the DHT22 Sensor

The DHT22 sensor can measure temperature and humidity. It has 3 pins - VCC, GND, and Data.

First, connect VCC to 5V and GND to Ground on the Arduino. Then connect the Data pin to Arduino pin D2. Add a 10k ohm pull-up resistor between the data line and 5V pin. This helps stabilize readings from the sensor.

Step 2: Connect the Rain Sensor

The rain sensor has an exposed PCB that detects rainfall. There are 3 pins - VCC, GND and D0.

Connect VCC to 5V and GND to Ground on the Arduino. The D0 pin connects to Arduino pin D3. This will allow us to detect rainfall events.

Step 3: Connect the Anemometer

The anemometer has a 3-cup wind speed sensor. It generates a pulse for each rotation.

There are 3 pins - VCC, GND and Out. Connect VCC to 5V and GND to Ground on the Arduino. The Out pin goes to Arduino pin D4. Later we can calculate wind speed based on the pulse frequency.

Step 4: Connect the LCD Display

The LCD display lets us view the sensor readings on the device. There are 16 pins that connect to the Arduino.

Follow the pin diagram on the back of the LCD display to hook it up properly to the Arduino. Common pins are VCC and Ground. The other pins connect to Arduino digital pins for sending data and commands.

Step 5: Connect the ESP8266 WiFi Module

The ESP8266 WiFi module allows the Arduino to connect to the internet. There are 4 pins - VCC, GND, TX and RX.

VCC to 3.3V, GND to Ground. The TX pin goes to Arduino RX pin and RX pin goes to Arduino TX pin. This enables serial communication between the ESP8266 and Arduino.

Step 6: Upload Arduino Sketch

With the hardware ready, it's time to program the Arduino. I used the DHT and LiquidCrystal libraries to read the sensors and control the LCD.

The loop function reads the DHT sensor, rain sensor and anemometer. It prints the values to the LCD and also publishes it to a server using the WiFi module.

Remember to include your WiFi name and password in the sketch! Once uploaded, the weather station starts collecting and displaying data.

Step 7: View Data on Cloud Platform

There are many IoT cloud platforms like ThingSpeak that let you visualize and store data from connected devices.

I used the ESP8266 to push my weather data to ThingSpeak. The upload interval can be adjusted in the code.

The ThingSpeak dashboard lets me see live graphs and charts of temperature, humidity, wind speed and rain values from the DIY weather station!


Building a weather station with Arduino only took a few inexpensive components and one evening of tinkering. The end result is a cool IoT project that provides weather insights in real time!

With the right sensors, you can even build arrays across large areas and create your own crowdsourced weather network. Hope this guide helped you get started building your own Arduino weather monitor! Let me know if you have any other questions.