Build a Weather App Using Python and OpenWeather API (Step-by-Step Guide)

Want to build your first real-world Python project? A Weather App is a perfect beginner-friendly project that helps you learn about APIs, JSON, and creating a functional Python program.

In this blog, you'll learn how to create a simple command-line Weather App using Python and the OpenWeatherMap API — from setup to final output!

🔧 Tools You’ll Need:

Python installed on your computer
Internet connection
A free API key from OpenWeatherMap

🌐 Step 1: Get OpenWeatherMap API Key

Go to https://openweathermap.org/api
Sign up for a free account
Navigate to the API keys section in your profile
Copy your API key (you’ll need it for the script)

📁 Step 2: Create a Python File

Create a file named weather_app.py

🧱 Step 3: Write the Python Code

python
import requests

def get_weather(city):
    API_KEY = "YOUR_API_KEY"  # Replace with your actual key
    BASE_URL = "http://api.openweathermap.org/data/2.5/weather"
    
    params = {
        'q': city,
        'appid': API_KEY,
        'units': 'metric'
    }

    response = requests.get(BASE_URL, params=params)
    data = response.json()

    if data.get("cod") != 200:
        print("City not found.")
        return

    weather = data['weather'][0]['description']
    temperature = data['main']['temp']
    humidity = data['main']['humidity']
    wind_speed = data['wind']['speed']

    print(f"📍 City: {city}")
    print(f"🌤️ Weather: {weather}")
    print(f"🌡️ Temperature: {temperature}°C")
    print(f"💧 Humidity: {humidity}%")
    print(f"🌬️ Wind Speed: {wind_speed} m/s")

# Run the app
city_name = input("Enter city name: ")
get_weather(city_name)

🧪 Step 4: Test the App

Open your terminal or command prompt
Run:

bash
python weather_app.py

Enter a city name (e.g., Delhi, London)
See the current weather data appear in your console!

⚙️ How It Works

We use the requests library to send a GET request to OpenWeather's API.
The response is in JSON format. We extract specific data like temperature, weather condition, humidity, etc.
The app then prints that information in a user-friendly way.

🚀 Bonus: Add More Features

Convert it into a GUI using Tkinter or PyQt
Add weather forecast for 5 days
Log data to a file
Show icons for weather conditions

🔒 Don't Forget

✅ Replace "YOUR_API_KEY" with your actual OpenWeather API key
✅ Handle API errors and invalid city inputs properly

✅ Final Thoughts

This Weather App is a great introduction to APIs, Python requests, and JSON. It’s lightweight, beginner-friendly, and helps you build a project you can be proud of.

💬 Want a GUI
version with Tkinter? Or want to deploy it on the web using Flask? Comment below and I’ll help you build it!