Originally Posted By OregonMouse
Another article today, pointing out the complete failure to forecast snow in Seattle Saturday evening.
Originally Posted By Cliff Mass
On Thursday, Portland was hit hard even though the forecast a day before called for a 20% chance of snow showers.


The things that stuck out at me when reading Cliff's blog was this:

Originally Posted By Cliff Mass
Why do weather forecast models fail?

There are at least three reasons:

The description of the atmosphere, the starting point of the simulation called the initialization, is flawed.

The physics of the model, how basic processes like radiation, clouds and precipitation are described, are flawed.

The forecasting problem is not possible considering the inherent uncertainties of atmospheric flows and the tendency for errors to grow in time.


And this:

Originally Posted By Cliff Mass
These disturbances were small in scale, fast moving, and developing offshore where data was sparse.


I do like the way Cliff describes the tools used and how they all work together. He does a great job of explaining how much we don't know about how the weather works, whereas too much of what we hear is how awesome the advanced technology they have is. As consumers of the products these weathermen create we like to think that all that techie stuff they use produces perfect output.

I'll offer that there was not really a "complete failure to forecast snow in Seattle" and instead that it was "not possible" to forecast the weather in Seattle. The two are not exactly the same if you consider that there were certainly not many meteorologist that were unaware of the lack of ability to produce an accurate forecast.

Originally Posted By Donald Rumsfeld
"Now what is the message there? The message is that there are no "knowns." There are things we know that we know. There are known unknowns. That is to say there are things that we now know we don't know. But there are also unknown unknowns. There are things we do not know we don't know. "


Well, something like that anyway grin
_________________________
--

"You want to go where?"