A nonlinear forecasting method was used to predict the behavior of a cloud
coverage time series several hours in advance. The method is based on the r
econstruction of a chaotic strange attractor using four years of cloud abso
rption data obtained from half-hourly Meteosat infrared images from Northwe
stern Spain. An exhaustive nonlinear analysis of the time series was carrie
d out to reconstruct the phase space of the underlying chaotic attractor. T
he forecast values are used by a non-hydrostatic meteorological model ARPS
for daily weather prediction and their results compared with surface temper
ature measurements from a meteorological station and a vertical sounding. T
he effect of noise in the time series is analyzed in terms of the predictio
n results.