<p>The variability of receiver code biases during geomagnetic storms is considered to negatively impact the performance of precise point positioning (PPP) and the accuracy of ionospheric total electron content (TEC) estimation, particularly at low-latitude regions. To mitigate the deviations of the receiver observation-specific biases (ROSB) biases caused by anomalous weather environments, this study systematically investigates the latitudinal characteristics of BDS-3 quad-frequency ROSB during geomagnetic storms. A piecewise correction model based on absolute differenced OSB (AdOSB) is proposed to compensate for ROSB deviations in abnormal weather environments through the advanced investigation of the ROSB time series. Meanwhile, the impact of model-corrected ROSB on the re-estimation of satellite OSB products and vertical TEC (VTEC) parameters through integrated network are evaluated with emphasis. The experimental results indicated that there were significant anomalies and latitudinal characteristics for ROSB at low-latitude regions during geomagnetic storms, with larger standard deviation (STD) compared to quiet days. After model correction, the time series of ROSB were more stable and mean absolute error (MAE) calculated with quiet days was improved by 54.50%. In addition, the code/phase OSB products at satellite-end had also gained promotion, the average STD for code OSB was improved by 11.02%, and the percentage within ± 0.15/0.25 cycles of ambiguity residuals for phase OSB had slight improvement. Meanwhile, the estimated VTEC was closer to reference values, and the retrieval consistency was improved by 35.04% on average, which was more pronounced at low-latitude stations. These conclusions further invalidated the validity of the proposed correction model and its impact on re-estimation parameters during geomagnetic storms.</p>