Perhaps I can help. After 17 years chasing the wind
Hang Gliding and 5 years soaring I have identified
one absolute rule in weather forecasting. I don't know
why it works but trust me it does.

'ONLY THE BAD FORECASTS ARE ALWAYS RIGHT'

At 18:12 04 July 2004, Jonathan Gere wrote:
Good weather on the 12 hour forecast became bad weather
on the 9 hour
forecast. Even worse in the cockpit. See the forecast
maps.

http://www.geocities.com/jgere34/12hrforecast.doc (167kB)

It's enough to make me wish for validation statistics
on soaring
forecasts of various durations.