Statistical analysis is performed for parameters in the inner and outer terrestrial magnetosphere as well as for the ionosphere during a strong geomagnetic storm. Dst value less than -150 nT was used as criteria and examples were chosen from the year 1999 through 2002. The parameters are interplanetary magnetic field (imf) and solar wind indices, storm disturbance index dst, total electron content TEC index, and normalized foF2 ratio. The time series data are obtained via satellites and ground stations. High frequency interplanetary magnetic field fluctuation correlates with large dst value and more fluctuation in TEC. The correlation coefficient r of about 0.9 (10 data points) for the peak Dst during the storm to the imf 4-min sigma B distribution tail area in the pre-storm 6-hr period suggests prediction capability. Similar correlation (r about 0.8) is also deduced for the peak Dst value to the peak deviation in the foF2 ratio. The cross correlation values of the various inter-dependent time series data are interpreted via the energy input mechanism. Latitude dependence of the ionosphere response is also discussed.