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In this work, we are analyzing incoherent scatter radar (ISR) data for H+, He+, and O+ ion fractions from the Arecibo Observatory for the period of June solstice (May, June, July, and August) for 1998 and 2000 with respect to solar flux and geomagnetic variations. Due to the strait dependence of the response of the ion fractions with the mentioned forcing, we isolated the real contribution of these parameters by local time and altitude as variation rates. Our results demonstrate that within the altitude range of this work (350 to 1250km) a positive (negative) response of the ion O+ (H+) with the variation of solar flux while the dependence of He+ rates presented three different behaviors dependents of time and altitude. Additionally, we found evidence of a small layer formation of He+ soon after the local midnight in altitudes around 875km with increased geomagnetic activity. A strong dependence with the variation of geomagnetic activity was detected for the ions of H+ and O+ post-midnight, which generated two layers. However, these layers were located in different altitudes, far from each other for about 340km.