今天似乎要下雨用英语怎么说

"It looks like it's going to rain today" 是表示今天要下雨的常用说法。
"It looks like" 是 "看起来" 的意思，"going to" 是将来时的标志词，表示将要发生的事情，"rain" 是 "下雨" 的意思。
例句及翻译:
"It looks like it's going to rain today, so I'll bring an umbrella." (今天看起来要下雨，所以我会带把伞)
"I heard the forecast and it looks like it's going to rain all week." (我听到天气预报了，看起来一整周都要下雨)
"I hope it doesn't rain today, but it looks like it's going to." (我希望今天不下雨，但看起来要下)