Re:Weather forecasts have become much more accurate
by amarcheschi on Tuesday March 12, 2024 @02:07PM
(#39682776)
Yup, a few days ago I made a python script to help me choose whether to get to uni by bike or by moped when it rains (given two coordinates I calculate the angle(bearing?) and checks whether it rains, and the angle from which the wind blows to see if I'll get all wet in the face) and I had a bit of a hard time figuring out why two different providers, windy and openweathermap, gave me 2 different wind results. Eventually, I found out they were using a different model, it took a bit of time tho, because windy only has increments of hours, while the other one was more granular
Windy.com lets you compare different models for a specific location, it also includes the size of the area per model: https://www.windy.com/?49.339,5.054,5
GFS is area is 22km, ECMWF 9km, ICON-D2 2.2Km, Arome 1.3Km, and UKV is 2Km. Even in a 1.3x1.3Km area it may not rain everywhere at the same time.
And then there's also the time element, so it's 1.3Kmx1.3Kmx1Hrs (or 3Hrs). So lot's of variation possible.