Introduction

Harmattan is a weather experience built around Nigerian cities.

The product began with a straightforward need: show weather clearly. It became more interesting when the interface stopped pretending location was merely a coordinate.

A contemporary weather product can be technically correct and still feel detached from the people using it. Harmattan takes the opposite approach. The city set, writing voice, condition labels, harmattan treatment, ambient sound, and companion game are shaped around a Nigerian context.

What Harmattan does

The application currently provides:

• live current weather;
• a multi-day forecast;
• Nigerian city search and quick city selection;
• Celsius and Fahrenheit;
• dark and light themes;
• contextual weather copy;
• dynamic condition visuals;
• ambient weather audio;
• persisted city, unit, theme, and sound preferences;
• a weather-powered companion game called 9jaRun.

Technical character

Harmattan is built without a frontend framework. The principal files are:

index.html
style.css
main.js
weather-data.js
audio.js
game.html
game.css
game.js

Live weather data comes from the Open-Meteo Forecast API. No weather API key is embedded in the project.

This guide documents what the repository actually implements. It does not invent an authentication layer, backend, database, push-notification system, or analytics service that is not present in the source.