The low-latitudinal cyclones (LLCs, originating between 5°N–10°N) constitute ≈40% of tropical cyclones (TCs) formed in the Bay of Bengal (BoB). We investigate the interannual variability of post-monsoonal (October to December) BoB LLCs and their teleconnection with El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD). It is found that the years with the fewer number of BoB LLCs are associated with anomalous equatorial easterlies that are largely connected with the El Niño and positive IOD. Likewise, equatorial westerly phases, often associated with the La Niña and negative IOD years, favour the LLC formation by providing the initial spin-up required for cyclogenesis. This teleconnection between ENSO/IOD and BoB TC frequency is confined in the low-latitudinal region with little influence for cyclogenesis north of 10°N during ENSO and IOD except during negative IOD. These results may help extend the lead time and improve the seasonal prediction of BoB TCs.

低纬度气旋（LLC，起源于 5°N–10°N）构成了在孟加拉湾 (BoB) 形成的热带气旋 (TC) 的约 40%。我们研究了季风后（10 月至 12 月）BoB LLC 的年际变化及其与厄尔尼诺南方涛动 (ENSO) 和印度洋偶极子 (IOD) 的遥相关。研究发现，BoB LLC 数量较少的年份与赤道东风异常有关，该异常主要与厄尔尼诺现象和正 IOD 相关。同样，通常与拉尼娜和负 IOD 年相关的赤道西风阶段通过提供气旋发生所需的初始旋转来促进 LLC 的形成。ENSO/IOD 和 BoB TC 频率之间的这种遥相关仅限于低纬度地区，除了负 IOD 期间，ENSO 和 IOD 期间对 10°N 以北的气旋生成影响不大。这些结果可能有助于延长交货时间并改善对 BoB TC 的季节性预测。