Завтра вечером ожидается сильный ветер.

the evening

Breakdown of Завтра вечером ожидается сильный ветер.

• завтра: tomorrow
• сильный: strong
• ветер: the wind

Questions & Answers about Завтра вечером ожидается сильный ветер.

Why is вечером in the instrumental case, with no preposition?

Вечером is the instrumental singular form of вечер. In Russian, parts of the day are very often used in the instrumental without a preposition to mean in the morning / in the evening / at night, etc.

So:

• утром = in the morning
• днём = in the daytime
• вечером = in the evening
• ночью = at night

That is why завтра вечером naturally means tomorrow evening.

What is завтра grammatically here?

Here завтра is an adverb of time, meaning tomorrow. It does not change form for case, number, or gender in this use.

So in завтра вечером, you have two time expressions together:

• завтра = tomorrow
• вечером = in the evening

Together they give a more specific time: tomorrow evening.

What exactly is ожидается, and why does it end in -ся?