הלוואי שירד שלג רק בערב, כשכבר נהיה בבית.

הלוואי is a wish word: if only, I wish, or sometimes hopefully, depending on context.

In this sentence, it introduces a wish about the future: the speaker wants the snow to come only later, in the evening.

The ש־ means that and introduces the clause that expresses the wish.

So הלוואי שירד שלג is literally something like if only that snow would fall.

You may also hear הלוואי ו... in Hebrew. Both patterns exist, but הלוואי ש... is completely natural.

Here it is understood as future: that it will snow / that snow will fall.

Unpointed Hebrew can hide this distinction. The spelling שירד could represent:

• שיָרַד = that fell
• שיֵרֵד = that will fall

In this sentence, because of הלוואי and the rest of the context, the intended reading is the future one: שיֵרֵד.

Hebrew commonly uses the verb ירד (to go down / fall) for rain and snow.

So ירד שלג is literally snow will fall / snow will come down, but in natural English we usually translate it as it will snow.

Unlike English, Hebrew does not need a dummy subject like it here.

Because Hebrew often allows, and sometimes prefers, verb–subject order, especially in sentences like this.

So שירד שלג is a very natural way to say that snow will fall.

You could also build a sentence with the subject first, but that would sound more marked or would put extra emphasis on the snow.

רק means only, and בערב means in the evening.

So רק בערב means only in the evening. The idea is: not earlier in the day, but specifically later, when it is already evening.

That is a very common difference between English and Hebrew.

In Hebrew, after time words like כש (when), future situations are usually expressed with the future tense:

• כשנגיע = when we arrive
• כשתראה = when you see
• כשנהיה בבית = when we’re home / when we will be at home

So even though English uses the present here, Hebrew normally uses the future.

כבר means already, and here it adds the idea of by that time.

So:

• כשנהיה בבית = when we’re home
• כשכבר נהיה בבית = when we’re already home

The version with כבר emphasizes that the speaker wants the snow to start only after they have already made it home.

Because בבית describes a location: at home / in the house.

By contrast, הביתה means homeward / to home and describes movement toward home.

So:

• נהיה בבית = we’ll be at home
• נלך הביתה = we’ll go home

Here the idea is being already there, so בבית is the correct choice.

Literally, it can mean in the house, but very often it is used idiomatically to mean at home.

In this sentence, at home is the best natural translation.

A natural pronunciation would be:

halvái sheyéred shéleg rak baérev, kshekvár nihyé babáyit

A more word-by-word guide:

• הלוואי = halvái
• שירד = sheyéred
• שלג = shéleg
• רק בערב = rak baérev
• כשכבר = kshekvár
• נהיה = nihyé
• בבית = babáyit