The Northeastern Argentine (NEA) region is one of the most productive and vulnerable to climate risk due to frequent extreme precipitation events (EPE). The present study aims to identify and explain the spatiotemporal distribution of precipitation in the NEA region to assess its heterogeneity. A cluster analysis from Ward’s hierarchical method was applied using observational precipitation collected at meteorological stations during 1959–2018. The elbow method and a nonhierarchical analysis of K-means were also useful to define the correct number of clusters. The three groups obtained responded to an east-west precipitation gradient that generated a zonal atmospheric circulation, and the positive anomalies mostly coincided with El Niño-Southern Oscillation (ENSO) events. Although they had similar seasonal rainfall and annual amplitudes, each subregion presented its specific variability at different temporal scales. Positive anomalies were more significant in the east of the NEA region, which is reflected in the displacement of isohyets in the last decades. Our results suggest that almost the entire NEA region is highly vulnerable to EPE, but with higher intensity and frequency in the center and east. Due to the agricultural and ecological importance of this region and the socioeconomic effects of EPE, studies with more detailed scales than the regional ones are necessary.

由于频繁的极端降水事件 (EPE)，阿根廷东北部 (NEA) 地区是生产力最高且易受气候风险影响的地区之一。本研究旨在识别和解释 NEA 地区降水的时空分布，以评估其异质性。使用 1959 年至 2018 年期间在气象站收集的观测降水，应用了沃德分层方法的聚类分析。肘部方法和 K 均值的非分层分析对于定义正确的聚类数也很有用。获得的三组响应产生了纬向大气环流的东西降水梯度，并且正异常大多与厄尔尼诺 - 南方涛动（ENSO）事件重合。虽然它们有相似的季节性降雨量和年振幅，每个次区域在不同的时间尺度上表现出其特定的可变性。正异常在 NEA 地区东部更为显着，这反映在过去几十年等距线的位移上。我们的结果表明，几乎整个 NEA 地区都非常容易受到 EPE 的影响，但在中部和东部的强度和频率更高。由于该地区在农业和生态方面的重要性以及 EPE 的社会经济影响，因此有必要进行比区域范围更详细的研究。但在中部和东部有更高的强度和频率。由于该地区在农业和生态方面的重要性以及 EPE 的社会经济影响，因此有必要进行比区域范围更详细的研究。但在中部和东部有更高的强度和频率。由于该地区在农业和生态方面的重要性以及 EPE 的社会经济影响，因此有必要进行比区域范围更详细的研究。