The purpose of this study is to present a wavelet interactive filtering and reconstruction technique and apply this to the solar wind magnetic field components detected at the L1 Lagrange point ~ 0.01 AU upstream of the Earth. This filtered interplanetary magnetic field (IMF) data is fed into a model to calculate a time series which we call AE*. This model was adjusted assuming that magnetic reconnection associated with southward directed IMF Bz is the main mechanism transferring energy into the magnetosphere. The calculated AE* was compared to the observed AE index using cross correlation analysis. The results show correlations as high as 0.90. Empirical removal of the high-frequency, short-wavelength Alfvénic component in the IMF by wavelet decomposition is shown to dramatically improve the correlation between AE* and the observed AE index. It is envisioned that this AE* can be used as the main input for a model to forecast relativistic electrons in the Earth's outer radiation belts, which are delayed by ~ 1 to 2 days from intense AE events.