Editor's Note: Chaos theory predicts that
weather forcasting becomes exponentially difficult as the
forcasting time is extended. There is a strong economic incentive
to push that limit far, if not too far.
Excerpts: Competing for companies and consumers
seeking reliable weather information, commercial forecasters are
sharply expanding the boundaries of their predictions.
Not long ago, five, six or seven days was considered the
practical limit for accurately forecasting temperature and
precipitation in a particular place at a particular time.
Last fall, Weather.com pushed its ZIP-code-by-ZIP- code
predictions out from 7 days to 10. (…) These forecasts are
the foundation on which the commercial products are built.
Last spring, Accuweather.com countered by offering detailed
forecasts up to 15 days ahead.