snow既可作名词（不可数）也可做动词。snows是动词“下雪”的一般时态里的第三人称单数形式。snowing是动词“下雪”的正在进行时态形式。

it looks like rain [raining]. 看来要下雨了。

it looks as if it’s going to rain. 像要下雨了。

it’s going to rain. 要下雨了。

it’s beginning to rain. 开始下雨了。

it’s clearing up. 天放晴了。

it’s going to be fine tomorrow. 明天将是个晴天。

it seems to be clearing up. 天似乎要转晴了。

it’s getting warmer (and warmer). 天气越来越暖和了。

Ithink there’ll be a storm soon. 我看很快就会有场暴风雨。

Idon’t think the rain would last long. 我看这雨不会下很久的。

Ithink the rain is going to last all day. 我看这雨会下个整天了。

we’re going to have a snowfall today. 今天会下雪了。

the rain is setting in. 雨下起来了。

I’m so glad it has turned out fine. 我真高兴结果是个好天。

I’m so sorry it has turned out wet. 真遗憾结果是个下雨天。

Ihope it will keep fine. 我希望天会一直晴下去。

Ihope the weather stays this way. 我希望天气总是这么好。

Ihope it won’t rain. 我希望天不会下雨。

the rain has stopped. 雨停了。

lovely day [weather], isn’t it? 天气真好，是吗?

nice and warm today, isn’t it? 今天挺暖和的，是吗?