Arduino DHT22 + LCD Weather Station using Wokwi Simulator (Step-by-Step Guide)

Arduino DHT22 + LCD
Weather Station

Build a real-time temperature & humidity monitor using Arduino UNO, DHT22 sensor, and a 16×2 LCD — simulated entirely in Wokwi. Beginner-friendly with full code and diagram.

~15 min read 4 Components Arduino C++

0Requirements

Components Required (Wokwi)

🔵

Arduino UNO

Microcontroller board

🌡️

DHT22 Sensor

Temp & Humidity

📟

16×2 LCD (I2C)

Character display

🔌

Jumper Wires

For connections

All components are available virtually — no physical hardware needed. Use the free Wokwi Arduino Simulator at wokwi.com.

1Wokwi Setup

Create Project in Wokwi

Go to wokwi.com
Click New Project
Select Arduino UNO as the board
In the component panel, search and add DHT22
Search and add LCD 16×2 I2C

2Wiring

Circuit Connections

🌡️ DHT22 Sensor

DHT22 Pin	Arduino Pin	Wire Color
VCC	5V	🔴 Red
GND	GND	⚫ Black
DATA	Digital Pin 2	🟢 Green

📟 16×2 LCD (Parallel, 4-bit mode)

LCD Pin	Arduino Pin	Wire Color
VSS / VDD Power	GND / 5V	⚫ / 🔴
V0 (contrast)	GND	⚫ Black
RS	Pin 7	🔵 Blue
RW	GND	⚫ Black
E (Enable)	Pin 8	🩵 Cyan
D4	Pin 9	🟡 Yellow
D5	Pin 10	🟠 Orange
D6	Pin 11	🟣 Purple
D7	Pin 12	⚪ Gray
A (backlight +)	5V	🔴 Red
K (backlight −)	GND	⚫ Black

3Wokwi Config

diagram.json

Paste this into the diagram.json tab in Wokwi to wire everything automatically.

diagram.json

{
  "version": 1,
  "author": "Arduino Weather Station",
  "editor": "wokwi",
  "parts": [
    { "type": "wokwi-arduino-uno", "id": "uno", "top": 77.4, "left": -77.4, "attrs": {} },
    {
      "type": "wokwi-dht22",
      "id": "dht1",
      "top": -95.7,
      "left": 225,
      "attrs": { "temperature": "24", "humidity": "65" }
    },
    { "type": "wokwi-lcd1602", "id": "lcd1", "top": -207.77, "left": -185.6, "attrs": {} }
  ],
  "connections": [
    [ "dht1:GND", "uno:GND.1", "black",  [ "h0" ] ],
    [ "dht1:VCC", "uno:5V",   "red",    [ "h0" ] ],
    [ "dht1:SDA", "uno:2",   "green",  [ "h0" ] ],
    [ "lcd1:VSS", "uno:GND.2", "black",  [ "h0" ] ],
    [ "lcd1:VDD", "uno:5V",   "red",    [ "h0" ] ],
    [ "lcd1:V0",  "uno:GND.2", "black",  [ "h0" ] ],
    [ "lcd1:RS",  "uno:7",   "blue",   [ "h0" ] ],
    [ "lcd1:RW",  "uno:GND.2", "black",  [ "h0" ] ],
    [ "lcd1:E",   "uno:8",   "cyan",   [ "h0" ] ],
    [ "lcd1:D4",  "uno:9",   "yellow", [ "h0" ] ],
    [ "lcd1:D5",  "uno:10",  "orange", [ "h0" ] ],
    [ "lcd1:D6",  "uno:11",  "purple", [ "h0" ] ],
    [ "lcd1:D7",  "uno:12",  "gray",   [ "h0" ] ],
    [ "lcd1:A",   "uno:5V",   "red",    [ "h0" ] ],
    [ "lcd1:K",   "uno:GND.2", "black",  [ "h0" ] ]
  ],
  "dependencies": {}
}

4Sketch

Arduino Code

LCD output preview:

Temp: 24.0°C 75.2°F

Humidity: 65.0% 💧

sketch.ino — Arduino C++

/*
 * Arduino Weather Station
 * DHT22 Temperature & Humidity Sensor with LCD Display
 * Created for Wokwi Simulator
 */

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

// DHT22 Sensor Configuration
#define DHTPIN    2      // DHT22 data pin → Arduino pin 2
#define DHTTYPE   DHT22  // DHT 22 (AM2302)

// Initialize DHT sensor
DHT dht(DHTPIN, DHTTYPE);

// LCD Configuration (RS, E, D4, D5, D6, D7)
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);

// Custom character: degree symbol
byte degreeSymbol[8] = {
  0b00110, 0b01001, 0b01001, 0b00110,
  0b00000, 0b00000, 0b00000, 0b00000
};

// Custom character: humidity drop
byte dropSymbol[8] = {
  0b00100, 0b00100, 0b01010, 0b01010,
  0b10001, 0b10001, 0b10001, 0b01110
};

void setup() {
  Serial.begin(9600);
  Serial.println("Weather Station Initializing...");

  dht.begin();
  lcd.begin(16, 2);
  lcd.createChar(0, degreeSymbol);
  lcd.createChar(1, dropSymbol);

  // Welcome splash screen
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print("Weather Station");
  lcd.setCursor(0, 1); lcd.print("Initializing...");
  delay(2000);
  lcd.clear();
}

void loop() {
  delay(2000);  // DHT22 sampling interval

  float humidity     = dht.readHumidity();
  float temperatureC = dht.readTemperature();
  float temperatureF = dht.readTemperature(true);

  // Guard against failed reads
  if (isnan(humidity) || isnan(temperatureC) || isnan(temperatureF)) {
    Serial.println("Failed to read from DHT sensor!");
    lcd.clear();
    lcd.setCursor(0, 0); lcd.print("Sensor Error!");
    lcd.setCursor(0, 1); lcd.print("Check Connection");
    return;
  }

  float heatIndexF = dht.computeHeatIndex(temperatureF, humidity);
  float heatIndexC = dht.computeHeatIndex(temperatureC, humidity, false);

  // Serial Monitor debug output
  Serial.print("Humidity: ");     Serial.print(humidity);
  Serial.print("% Temp: ");       Serial.print(temperatureC);
  Serial.print("°C / ");          Serial.print(temperatureF);
  Serial.print("°F  Heat: ");     Serial.print(heatIndexC);
  Serial.println("°C");

  // ── Screen 1: Temperature + Humidity ──
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperatureC, 1);
  lcd.write(byte(0));    // ° symbol
  lcd.print("C ");
  lcd.print(temperatureF, 1);
  lcd.write(byte(0));
  lcd.print("F");

  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity, 1);
  lcd.print("%");
  lcd.write(byte(1));    // 💧 drop symbol

  delay(5000);

  // ── Screen 2: Heat Index ──
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print("Heat Index:");
  lcd.setCursor(0, 1);
  lcd.print(heatIndexC, 1); lcd.write(byte(0)); lcd.print("C / ");
  lcd.print(heatIndexF, 1); lcd.write(byte(0)); lcd.print("F");

  delay(3000);
}

5Libraries

Required Libraries

Add these via Wokwi's library manager or libraries.txt:

        DHT sensor library

        by Adafruit — reads DHT22 data

        LiquidCrystal

        Built-in — drives 16×2 LCD

        Adafruit Unified Sensor

        Required by DHT library

6Simulate

Run Simulation

Paste the Code

Copy the sketch into Wokwi's code editor tab.

Add diagram.json

Paste the diagram.json to auto-wire all components.

Start Simulation

Click the green ▶ Play button to run.

Adjust Sensor

Click the DHT22 to change temperature & humidity values live.

Run Free Simulation on Wokwi

✅ Result

Project Output

Temp: 24.0°C 75.2°F

Humidity: 65.0% 💧

🌡️ Temperature in °C & °F

💧 Humidity in %

🔥 Heat Index

⏱️ Updates every 2 seconds

🖥️ Runs in Wokwi — no hardware

More Arduino Projects

🟢 Beginner — Foundation & Basics

01Intro to Wokwi Simulator 02Multiple LED Patterns (Traffic Light) 03Knight Rider LED Chaser 04RGB LED Color Mixing 05Potentiometer Analog Input 06Buzzer Sound Generation 07Photoresistor Light Sensor

🔵 Intermediate — Displays & Sensors

0116×2 LCD Text Output 0216×2 I2C LCD Display 037-Segment Display Counter 044-Digit 7-Segment Clock 05LCD + Ultrasonic Parking Sensor 06DHT22 + LCD Weather Station ← You are here

🔴 Advanced — Motors, Security & Expert

01Dual Servo Motor + OLED 02Stepper Motor (28BYJ-48) 03Password-Based Lock 04RFID Access Control (MFRC522) 05Biometric Dual Authentication

📡 IoT & Advanced Displays

01Weather Station (Multi-Sensor) 02ColorChord Musical Sequencer 0332×32 LED Matrix (Arduino Mega) 04OLED Graphics (SSD1306 128×64)

ROBOTICS

Search This Blog