Chiayi County received torrential rain throughout the night on May 21, resulting in falling rocks along the main access road for Alishan Township's Dabang Village. Traffic was disrupted at one point and repairs were undertaken on the morning of May 22. As of noon, all of the fallen rocks had been removed. Chiayi County's Dongshih Township also received a lot of rain on the morning of May 22 and floodwater levels reached a half-tire height. Three elementary schools suspended all classes after 12:30 p.m.
A night of pouring rain caused a shower of rocks along the main access road to Alishan Township's Dabang Township. Workers cleared Chiayi Route 169 of debris on the morning of the 22nd. Roads in the Alishan area are open right now, but there have been reports of falling rocks here and there due to heavy rain in mountainous parts. Falling rocks also disrupted traffic in the villages of Shanmei and Laiji. The Alishan Forest Railway and Alishan National Forest Recreation Area's branch lines were shut down preemptively on the 22nd. Due to unstable weather all over the area and road safety considerations, we decided to shut everything down preemptively. Over in Dongshih Township's Yongtun Village, the water level in low-lying areas reached half a tire high after an hour of rain. They finished pumping pond water and drainage water around 2 a.m. With further torrential rains expected, water pumps are being sent to Chiayi. 嘉義阿里山區，下游溪水暴漲水流湍急，經過一夜暴雨，阿里山鄉"達邦村"，對外主要道路"嘉169線"，邊坡零星落石，交通一度中斷，一怎工作人員開著機具清除落石加速搶通。 嘉義縣阿里山鄉公所課長 吳秀豐表示：「目前我們阿里山這邊，阿里山鄉這邊的道路，目前都是通的，但是因為山區，目前因雨量下的比較多，就是會有零星的落石。」 另外，山美村、來吉村也發生落石阻斷道路事件。阿里山鄉長表示，從21號晚上10點多，就陸續傳出災情。就怕雨勢不斷，阿里山森鐵本線，及阿里山國家森林遊樂區支線，各班次列車，22號也實施預警性停駛。 阿里山林業鐵路及文化資產管理處鐵路服務科長 洪淑霞表示：「那我們也考慮到說，因為整個山區的一個氣候，這樣的不穩定豪雨的話，可能會造成路線的安全的一個疑慮，所以我們就是等於這個預警性的停駛啦。」 不僅，嘉義山區傳災情，嘉縣東石鄉永屯村，從凌晨零時過後，下起了約1小時的強降雨，一度造成部分低潌地區，水淹半個輪胎高。 嘉義縣東石鄉公所建設課長 李冠昱表示：「他們大概(凌晨)兩點多，就把池子裡面的水，還有引水道裡面的水，都已經抽到最低水位了這樣子。」 受到滯留鋒面及西南氣流影響，雨還會繼續下，嘉義地區低窪處，目前進駐大型抽水機， 預防豪大雨淹水情況。