Утром я открыла шторы и увидела, что во дворе идёт снег.

Утром is the instrumental singular form of утро.

In Russian, some time expressions are commonly used in the instrumental case to mean during / in that part of the day:

• утром = in the morning
• днём = in the daytime
• вечером = in the evening

So Утром here simply means in the morning.
Using в утро would not sound natural in this everyday meaning.

Because the speaker/narrator is female.

In the Russian past tense, verbs agree with the subject in gender and number:

• masculine: открыл, увидел
• feminine: открыла, увидела
• plural: открыли, увидели

So я открыла and я увидела tell you that я refers to a woman or girl.

A useful thing to remember: Russian past tense does not show person the way present tense does. The form tells you gender/number, not I / you / he.

This is very normal in Russian.

Russian does not backshift tenses as much as English does. After a past verb like увидела, Russian can still use the present tense in the subordinate clause to describe what was happening at that moment:

• увидела, что идёт снег = saw that it was snowing

So идёт is present in form, but in English the natural translation is often was snowing.

This present tense makes the scene feel immediate, as if you are seeing it through the speaker’s eyes at that moment.

They describe two completed events:

1. she opened the curtains
2. she saw/noticed that it was snowing

Perfective verbs are often used for single, completed actions in a sequence.

Here:

• открыла = completed the act of opening
• увидела = had the moment of noticing/seeing

But идёт is different: snowing is an ongoing process, not a completed event. That is why the sentence mixes completed actions with an ongoing situation.

Шторы is the accusative plural here, because it is the direct object of открыла:

• открыла что? → шторы

The dictionary form is also шторы because the noun is normally used in the plural.

Since шторы is an inanimate noun, its accusative plural looks the same as its nominative plural. So the form does not change:

• nominative plural: шторы
• accusative plural: шторы

There is no comma before и because открыла and увидела are two coordinated verbs with the same subject я:

• я открыла шторы и увидела...

That is a simple coordination, so no comma is needed there.

But что introduces a subordinate clause:

• увидела, что во дворе идёт снег

In Russian, a subordinate clause is normally separated by a comma, so the comma before что is required.

There are two things going on here:

1. Case:
After в / во meaning in for location, Russian uses the prepositional case:

• двор → во дворе

So в двор would be wrong here, because that would suggest motion into the yard and would normally require the accusative.

2. Preposition form:
Russian often uses во instead of в before awkward consonant clusters for easier pronunciation.

Since двор begins with дв-, во дворе sounds natural and standard.

So:

• во дворе = in the yard / in the courtyard

Двор usually means a yard, courtyard, or the outdoor area around a building.

So во дворе suggests the speaker is looking out and seeing the snow in the area outside the building, not just somewhere abstractly outside.

Depending on context, English might translate it as:

• in the yard
• in the courtyard
• outside in the yard

That is just a standard Russian weather expression.

Russian often says:

• идёт дождь = it is raining
• идёт снег = it is snowing

So although идти literally means to go, in weather expressions it means something like to be falling / to be coming down.

Also, Russian does not need a dummy subject like English it. English says it is snowing, but Russian simply says идёт снег.

Yes, both are possible, but the emphasis changes.

• идёт снег is a very natural way to present the scene: it’s snowing
• снег идёт puts a little more emphasis on snow

Russian word order is flexible, and it often reflects emphasis or what the speaker wants to foreground.

In this sentence, во дворе идёт снег sounds smooth and natural after увидела, что...

Yes, absolutely.

Russian commonly says открыть шторы for opening / pulling back curtains. English may also say open the curtains, draw the curtains, or pull the curtains open, depending on context.

So открыла шторы is perfectly normal Russian.

If you wanted to be more specific about physically moving them apart, Russian could also use verbs like раздвинуть, but открыть шторы is standard and natural.

Quite flexible, but this version is very natural.

• Утром comes first to set the time frame.
• я follows in a neutral way.
• Then the completed actions come in sequence: открыла... и увидела...
• In the subordinate clause, во дворе comes early to set the scene.

You could also say:

• Я утром открыла шторы и увидела, что во дворе идёт снег.

That is also correct. The difference is mostly about emphasis and flow, not basic meaning.

So the word order here is not random; it is a natural, neutral way to tell the story.