本文使用台電公司全閃電偵測系統(total lightning detection system, TLDS)的雲中(intra-cloud, IC)閃電 資料，針對全臺850個雨量站為中心的72 x 72 km2正方形分析區，以分析區內至少1個雨量站出現10 mm (10 mm)-1以上雨量為對流性降雨事件之定義，探討2015年5至10月午後時段各區達到IC躍升 (jump)數量門檻值的閃電活動，與該分析區對流性降雨事件之關聯程度。診斷結果顯示在5個5分鐘時 段1C數量的時間滑動平均之下，IC數量平均值加2倍標準差為最佳之IC jump門檻；全臺之後符(post agreement)命中率平均值超過0.61、最大值接近0.87 ,顯示IC jump對於臺灣對流性降雨有預警應用價 值。比對後符與前估(prefigurance)兩種結果顯示臺北盆地與其周圍山區、部分宜蘭縣，及南投與中部縣 市交界一帶，適用IC jump預警對流性降雨；臺灣西南部應用IC jump預警對流性降雨有參考價值，但 需進一步了解IC定位不確定性的影響及當地對流之雲物理結構特徵。

Based on the inter- and intra-cloud (IC) lightning data of Taipower's total lightning detection system (TLDS), this study analyzed the relationship between the lightning activity reaching the IC jump activation and the occurrence of convective rainfall event during 04:00〜12:50 UTC from May to October 2015. Total 850 analysis areas, covering 72 x 72 km2, are centered on raingauge stations. The convective rainfall event in each analysis area is defined as the presence of at least one station with rainfall amount greater and equal to 10 mm (10 min)-1. By a five 5-min intervals moving average, the results show that (1) the average IC number plus two times the standard deviation is the best option for IC jump calculation in this study; (2) the mean and maximum post-agreement are about 0.61 and 0.87, respectively, indicating that IC jump can be applied to nowcast convective rainfall in Taiwan. The results of comparing the prefigurance to the post-agreement also suggest that (1) it is well suited to apply the IC jump to the convective rainfall nowcasting in the vicinity of the Taipei Basin and its surrounding mountainous area, part of Yilan County, and the border of Nantou and central counties; (2) the application of IC jump to convective rainfall nowcasting is of great potential in the southwestern Taiwan, but it is necessary for further investigations on the cloud microphysical properties and the IC position uncertainty.