How to Build a Simple Arduino Weather Station with Temperature and Humidity Sensors

Introduction

Building your own Arduino weather station is a great way to get started with IoT projects. With just a few basic components, you can start measuring temperature and humidity data and display it on an LCD screen. This project is perfect for beginner makers looking to get hands-on experience with Arduino and sensor modules.

In this comprehensive guide, I will walk you through the entire process of assembling an Arduino weather station from start to finish. We will cover:

Components Needed

To build the Arduino weather station, you will need the following components:

Arduino Uno Board

The Arduino Uno is the microcontroller board that will serve as the brain of our weather station. It will collect sensor data and control the LCD display. The Uno is a great choice because of its ease of use, breadth of documentation and sample projects available online.

DHT11 Temperature and Humidity Sensor

The DHT11 is a basic digital temperature and humidity sensor. It provides fairly accurate measurements and communicates with the Arduino over a single digital pin. For a simple weather station, the DHT11 offers good value for money compared to more advanced sensors.

16x2 LCD Display

A 16x2 LCD display will enable us to show the current temperature and humidity readings on a screen. The 16x2 means it has 2 rows that can each display 16 characters. We will connect it to the Arduino with just a few wires.

Breadboard

A breadboard allows us to easily connect the components without soldering. The Arduino and other components can be plugged in and out of the breadboard with jumper wires.

Jumper wires

Jumper wires are used to make all the connections between components on the breadboard and Arduino. Different colored wires make it easier to keep track of connections.

Resistors

220 ohm resistors are used in the wiring for the best communication with the LCD display. Resistors prevent too much current flow.

This covers the key components needed. In addition, you may need a box, plastic or cardboard, to mount the project neatly together.

Circuit Diagram

Before we begin hooking everything up, here is the circuit diagram for the Arduino weather station:

The DHT11 sensor, LCD screen and breadboard will all be connected to the Arduino through various digital and analog pins. We will go through each connection in detail during assembly.

Assembling the Circuit

With all the components ready, we can now start assembling the physical circuit for our weather station. Follow these steps closely:

Step 1 - Insert the Arduino

Insert the Arduino Uno board firmly into the center of your breadboard. Make sure it straddles the divide between the two halves.

Step 2 - Connect the DHT11 sensor

Plug the DHT11 sensor into the breadboard on the right side of the Arduino.

Connect the VCC pin on the DHT11 to the 5V pin on the Arduino. The 5V pin supplies power to the sensor.

Connect the GND pin on the DHT11 to GND on the Arduino. This completes the circuit.

Finally, connect the SIGNAL pin on the DHT11 to Digital pin 2 on the Arduino. This allows data communication between the two devices.

Step 3 - Connect the 16x2 LCD

On the left side of the Arduino, insert the 16x2 LCD display module into the breadboard.

Connect the VSS pin to GND and the VDD pin to 5V, for power.

Connect VO to the potentiometer on the display module. This controls display contrast.

Finally, connect the RS, Enable, and Data pins to Arduino pins 12, 11 and 5 respectively. These allow communication of display data.

Step 4 - Connect remaining wires

Use jumper wires to make all remaining connections between the Arduino and other components as shown in the circuit diagram.

Be sure to place 220 ohm resistors in the wiring between the Arduino and LCD pins 4 and 6.

Once all wires are securely in place, double check that all points match with the circuit diagram.

Loading the Code

Now that our Arduino weather station circuit is assembled, we need to upload the code that will allow it to function. Here are the steps:

Step 1 - Install DHT and LCD libraries

In the Arduino IDE, search for and install the DHT sensor and LiquidCrystal I2C libraries using the library manager. These contain important code to run the DHT11 and LCD.

Step 2 - Get sample sketch

Search online for Arduino DHT11 LCD weather station sample code. You should find many examples and sketches to download.

Step 3 - Modify and upload code

Open the sketch in the Arduino IDE. Make sure to modify according to the pin numbers you have used.

Select the right Arduino board and COM port. Then upload the code.

Step 4 - Open serial monitor

After uploading, open the serial monitor window to check the sensor outputs.

If you see temperature and humidity values, the code is working!

Testing and Usage

With the code uploaded successfully, our weather station should be fully functional!

Here are some final steps to test it out:

Check the temperature and humidity values updating on the LCD screen.
Breathe on the DHT11 sensor and verify the humidity level rises.
Modify the Arduino code to display additional data points, customize LCD text, set data logging intervals, etc.
Consider 3D printing an enclosure for the components to integrate them together as one permanent weather station unit.
Over time, take note of temperature and humidity daily patterns in your location. Identify the times of high and low values.

And that's it! With the ability to measure temperature and humidity, you now have the core elements for an Arduino-based weather tracking system.

Future Enhancements

While this covers the basics, there are many possibilities to enhance your Arduino weather station:

Add other environmental sensors like barometric pressure, wind speed, rainfall, etc.
Use a micro SD card module to store and log all the data.
Upload data to cloud platforms like ThingSpeak to view sensor readings from anywhere.
Add WiFi connectivity for weather updates to mobile and web apps.
Use a real-time clock module for timestamping data.
Create a weather forecasting model using machine learning on the data.
Build a stand-alone portable weather station with battery pack and solar panel.

So by starting out with a simple temperature and humidity station, you can gradually keep adding new features and capabilities as you advance your Arduino and IoT skills! The possibilities are endless.

Let me know if you have any other questions about my guide to building an Arduino weather station. I'm happy to provide any clarification needed and wish you the best with your projects!