Arduino Weather Station

Overview

A couple days ago I saw some really cool Arduino projects on reddit and decided to get myself an Arduino kit. After trying out all the sensors included I got the idea to make my own weather station with the help of an LCD, a DHT11 temperature and humidity sensor, and an Arduino Uno.

Components

• Arduino Uno — The brain of the project
• 16×2 LCD — Displays temperature and humidity readings
• DHT11 sensor — Measures temperature and humidity
• 10kΩ potentiometer — Adjusts LCD contrast
• Breadboard & jumper wires — For connections

Wiring

LCD Connections

LCD pin	Arduino pin
VSS	GND
RW	GND
K	GND
RS	7
E	8
D4	9
D5	10
D6	11
D7	12
VDD	5V
A (backlight)	5V

Potentiometer: Place across breadboard halves. Two outer pins → GND and 5V. Middle pin → LCD V0 (contrast).

DHT11: Left pin → Arduino pin 2. Middle pin → 5V. Right pin → GND.

Code

#include "DHT.h"
#include <LiquidCrystal.h>

#define DHTPIN 2
#define DHTTYPE DHT11

DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);

void setup() {
  dht.begin();
  lcd.begin(16, 2);
}

void loop() {
  delay(500);
  float h = dht.readHumidity();
  float t = dht.readTemperature();

  lcd.print("Humid: ");
  lcd.print(h);
  lcd.print("%");
  lcd.setCursor(0, 1);
  lcd.print("Temp: ");
  lcd.print(t);
  lcd.print((char)223);
  lcd.print("C");
  delay(2000);
  lcd.clear();
}

Finished Product

The LCD shows Humidity (%) and Temperature (°C) readings, which are described as accurate.

Optional: Mini Version

Built on a tiny breadboard fitted onto a prototyping shield — same wiring but much tighter layout. The advantage is portability: carry only the Arduino and a battery.

Related Projects

• IoT ESP8266 Weather Station — The Wi-Fi connected upgrade