How Weather Modeling Gets Better
Dr_Ish writes: Bob Henson over at Weather Underground has posted a fascinating discussion of the recent improvements made to the major weather models that are used to forecast hurricanes and the like. The post also included interesting links that explain more about the models. Quoting: "The latest version of the ECMWF model, introduced in May, has significant changes to model physics and the ways in which observations are brought into and used within the model. The overall improvements include better portrayal of clouds and precipitation, including a more accurate depiction of intense rainfall. The main effect of the model upgrade for tropical cyclones is slightly lower central pressure. During the first 3 days of a forecast, the ECMWF has tended to have a slight weak bias on tropical cyclones; the new version is closer to the mark."
I can understand why they get predictions about the future wrong, that bit is hard. What gets me is when the prediction for right now is at odds with what is actually happening. It seems like there is a significant delay between sensors on the ground taking a reading and the models being updated.
Apart from it being slightly comical when the guy on TV says sun is out but looking through the window I can see rain, it makes short term predictions useless. If they say it will rain this evening when I want to go out but the forecast for right now is wrong, what am I supposed to do with that information?
At best you get a vague prediction of the weather in the next few days, but the exact timing of events tends to vary quite a bit from what they say. It doesn't help that in the UK TV weather forecasts are delivered in the most confusing way possible, but fortunately we have the internet now.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Weather often varies dramatically over small distances. It may be sunny at the studio and raining 1/2 a mile away where you are. Rain predictions are not 50% chance that a given spot will get an inch of rain. The prediction is that 50% of a large area will get a inch of rain. Big difference between those.
My experience has been that the predictions are usually quite accurate about what will happen, but is less precise about when. When they predict a front moving in, you can count on those thunderstorms, but don't always count on the storms starting exactly at 5pm.
The article mostly talks about predicting tropical storms, and for this the modelling of exactly what the path of the storm is going to be is critical. It does see that the predictions of storm tracks is getting better.
http://www.geoffreylandis.com