Kad je nebo bez oblaka, pogled na more je ljepši.

Yes. Kad means when in this sentence.

Here it introduces a time clause:

• Kad je nebo bez oblaka = When the sky is cloudless / When there are no clouds in the sky

A very common longer form is kada, and both are normal:

• Kad je nebo bez oblaka...
• Kada je nebo bez oblaka...

In everyday speech, kad is especially common.

Because there are really two clauses, and each one needs the verb to be:

1. Kad je nebo bez oblaka
   = When the sky is without clouds

2. pogled na more je ljepši
   = the view of the sea is more beautiful

So the first je belongs to the time clause, and the second je belongs to the main clause.

After the preposition bez (without), Croatian uses the genitive case.

So:

• oblak = cloud (dictionary form, nominative singular)
• bez oblaka = without a cloud / without clouds

This is why you do not say bez oblak.

A learner should remember this pattern:

• bez + genitive

Some similar examples:

• bez šećera = without sugar
• bez vode = without water
• bez problema = without problems

It can function idiomatically as cloudless or without clouds.

Literally, bez oblaka is without clouds / without a cloud, but in natural English you would often translate the whole part as:

• When the sky is cloudless

Croatian often uses this kind of structure where English may prefer an adjective.

Because pogled na more means a view toward the sea / a view of the sea, and here na expresses direction or orientation toward something, which takes the accusative.

So:

• more = accusative singular
• na more = toward the sea / of the sea in this expression

Compare:

• pogled na more = a view of the sea
• biti na moru = to be at the seaside / on the sea, where na moru is locative

So this is not about physical location here, but about what the view is directed at.

Pogled literally means view, look, or glance, depending on context.

In this sentence, it means view:

• pogled na more = the view of the sea

This is a very common expression. It refers to what you can see, especially from a place like a window, terrace, hill, or hotel room.

Yes. Ljepši is the comparative of lijep (beautiful, nice).

• lijep = beautiful
• ljepši = more beautiful / nicer

So:

• pogled na more je ljepši = the view of the sea is more beautiful / nicer

The stem changes a little:

• lijep → ljepši

That kind of change is normal in Croatian comparatives.

That is normal. Croatian, like English, can leave the comparison implicit.

So je ljepši means:

• is nicer
• is more beautiful

The full comparison is understood from context, for example:

• nicer than when the sky is cloudy
• nicer than usual
• nicer than under other conditions

Croatian often does not need to spell that out if it is obvious.

Because ljepši agrees with pogled, and pogled is a masculine singular noun.

So:

• pogled = masculine singular
• therefore the predicate adjective is ljepši

Compare:

• Pogled je ljepši. = The view is nicer.
• More je ljepše. = The sea is nicer / more beautiful.

Here more is neuter, so it would take ljepše, but pogled is masculine, so we use ljepši.

Here are the genders:

• nebo = neuter
• oblak = masculine
• pogled = masculine
• more = neuter

This matters because adjectives and some other words agree with the noun:

• nebo is neuter
• pogled is masculine, so ljepši is masculine singular

Croatian word order is more flexible than English word order, but there are still strong patterns.

In this clause:

• Kad je nebo bez oblaka

the verb je comes very early because Croatian clitics like je tend to appear in the second position of the clause.

That is why learners often see sentences like:

• Kad je vrijeme lijepo...
• Ako je moguće...
• On je ovdje.

So although Croatian word order is flexible, je often appears near the beginning for grammatical reasons.

Because the sentence begins with a subordinate clause:

• Kad je nebo bez oblaka, ... = When the sky is cloudless, ...

Croatian normally uses a comma to separate that introductory dependent clause from the main clause.

So the structure is:

• subordinate clause: Kad je nebo bez oblaka
• main clause: pogled na more je ljepši

This is similar to English punctuation in sentences like:

• When the sky is cloudless, the view of the sea is nicer.

Yes, in many contexts that would work.

• vedro nebo = clear sky
• Kad je nebo vedro = When the sky is clear

That is a more directly adjectival way to express a similar idea.

But bez oblaka is also very natural and specifically emphasizes the absence of clouds:

• Kad je nebo bez oblaka = When the sky is without clouds / cloudless

So the two are similar, but bez oblaka is a bit more literal and image-based.

Yes, it is natural and correct.

It has a very normal structure:

• Kad... for a time condition
• bez + genitive
• pogled na more
• comparative adjective ljepši

A Croatian speaker might also phrase the idea in slightly different ways, such as:

• Kad nema oblaka, pogled na more je ljepši.
• Kad je nebo vedro, pogled na more je ljepši.

But the original sentence is perfectly natural.