RainBalance: Alleviating Dual Imbalance in GNSS-based Precipitation Nowcasting via Continuous Probability Modeling

Yifang Zhang; Shengwu Xiong; Henan Wang; Wenjie Yin; Jiawang Peng; Duan Zhou; Yuqiang Zhang; Chen Zhou; Hua Chen; Qile Zhao; Pengfei Duan

arXiv · 2601.06137

RainBalance: Alleviating Dual Imbalance in GNSS-based Precipitation Nowcasting via Continuous Probability Modeling

Yifang Zhang·Shengwu Xiong·Henan Wang·Wenjie Yin·Jiawang Peng·Duan Zhou·Yuqiang Zhang·Chen Zhou·Hua Chen·Qile Zhao·Pengfei Duan

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Abstract

Global navigation satellite systems (GNSS) station-based Precipitation Nowcasting aims to predict rainfall within the next 0-6 hours by leveraging a GNSS station's historical observations of precipitation, GNSS-PWV, and related meteorological variables, which is crucial for disaster mitigation and real-time decision-making. In recent years, time-series forecasting approaches have been extensively applied to GNSS station-based precipitation nowcasting. However, the highly imbalanced temporal distribution of precipitation, marked not only by the dominance of non-rainfall events but also by the scarcity of extreme precipitation samples, significantly limits model performance in practical applications. To address the dual imbalance problem in precipitation nowcasting, we propose a continuous probability modeling-based framework, RainBalance. This plug-and-play module performs clustering for each input sample to obtain its cluster probability distribution, which is further mapped into a continuous latent space via a variational autoencoder (VAE). By learning in this continuous probabilistic space, the task is reformulated from fitting single and imbalance-prone precipitation labels to modeling continuous probabilistic label distributions, thereby alleviating the imbalance issue. We integrate this module into multiple state-of-the-art models and observe consistent performance gains. Comprehensive statistical analysis and ablation studies further validate the effectiveness of our approach.

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Yifang Zhang, Shengwu Xiong, Henan Wang, Wenjie Yin, Jiawang Peng, Duan Zhou, Yuqiang Zhang, Chen Zhou, Hua Chen, Qile Zhao, Pengfei Duan. 2026-01-05. RainBalance: Alleviating Dual Imbalance in GNSS-based Precipitation Nowcasting via Continuous Probability Modeling. https://arxiv.org/abs/2601.06137

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