I feel like for the last 20 years I’ve felt like tomorrow’s forecast is very accurate, 2 days from now is an educated guess (if it says it’s raining, it’ll rain, but not sure what time of day) and 3+ days is unknown.
What advancements have we made in meteorology and what are the current limitations for weather forecasting?
I’ve definitely seen my phone be very accurate in forecasts for the current day like “in 16 mins, it’ll rain for 22 mins and then stop for an hour”
In: Planetary Science
[Here’s a plot showing how forecast accuracy has improved from the 1980s to today](https://ourworldindata.org/images/published/improved-weather-forecasting_1350.png). So yes, there have been advancements made. And that’s mostly because of the rapid progress in computing technology.
What makes weather prediction difficult is that it is a chaotic system, which means that very small changes in initial conditions can lead to wildly different outcomes over time. This is an issue because no simulation is perfect – we cannot measure exactly how fast the wind is blowing on every square millimeter of the Earth’s surface, and even if we could we don’t have enough computing power to simulate it with that resolution.
But the nature of chaotic systems is that the errors grow exponentially with time, so if you want to predict further into the future you need *exponentially* more accurate initial data, and exponentially more computing power, in order to have a linear increase in how far ahead you can predict. That’s why, despite *massively* more sophisticated models, and computing power that would have been unthinkable 40 years ago, today’s 7-day forecast is still worse than a 3-day forecast from the 80s.
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