There are countless weather websites and apps in the world, but somehow none of them ever felt exactly right for me. They either showed too much information or too little, included ads, or presented the forecast in a way that didn’t match how I wanted to use it.
About ten years ago, I made my first attempt to create my own weather app named SimpelWeer (Dutch for “simple weather”). As an experienced UX designer, designing the interface was relatively easy. But the coding proved too complicated for my limited programming skills, so after a few days I gave up.
ChatGPT 3.5
Then AI entered the picture.
For me – like for most people – the new AI era really started with the launch of ChatGPT in November 2022. I was amazed by what suddenly seemed possible with this new generation of chatbot.
A few months later, in March 2023, I did a small experiment. I asked ChatGPT 3.5 to make a website showing the weather forecast for Amsterdam. With the prompt “Create a website in HTML, CSS and JavaScript that shows the weather forecast for Amsterdam, The Netherlands” and an API key, it created a working weather site for me in about five minutes (see video below). I hadn’t written any code myself. I was stunned.
ChatGPT o3
I hadn’t taken the last version any further, but two years later, in May 2025, I picked up my original idea again: making my perfect weather app. This time I used ChatGPT o3 (one of the first reasoning models) and spent a few days prompting, testing, and checking the AI’s output.
The result was a site I named MyMeteo. It partly did what I wanted: it showed temperature, wind, weather icons, and included a location selector. But then I got stuck on the rain radar. For some reason, the AI wasn’t able to create an animated rain radar map showing the conditions for the next few hours. After a while, I gave up again.
That version is still online here: https://onlinecaveman.com/rest/mymeteo1
ChatGPT 5.5
Last week, I decided to give it another try. This time I used ChatGPT 5.5 in Codex, OpenAI’s agentic desktop app. Clearly, AI coding had made another leap forward. After only a day and a half of work, I had a working weather website that finally behaved the way I wanted.
The AI’s coding ability was impressive, but that was not the only thing that surprised me. It also produced pretty good designs, suggested useful new functionality, and helped me avoid the endless loop of prompting and broken code that I had run into before.
You can try the last version of MyMeteo here: https://onlinecaveman.com/rest/mymeteo2
The app is far from perfect yet. For instance, I haven’t managed to get more than three hours of rain radar data for the Netherlands, and with more time I could certainly improve both the design and functionality. But considering the relatively small amount of time I spent on it, I’m happy with the result.
Inadvertently, my weather app had become my personal AI coding benchmark. And today, AI coding capabilities are genuinely impressive. We are getting very close to a point where almost anyone can create a website or app without a technical background.
I’m very curious to see what other people will create next.
*** Update 24 May 2026 ***
After May 5, 2026, I continued to work on MyMeteo a bit. For instance, I added 8 hour rain radar data for the Netherlands, designed clearer weather icons and added hourly forecasts inside the 5-day forecast. I even got the app its own URL: https://mymeteo.nl
Other AI-related posts
- Vibecoding a Snake game in a few hours (23 Apr 2026)
- AI is sprinting while most of us are still tying our shoes (6 Jun 2025)
- The Adventures of Little Man Max (31 Mar 2017)
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