Learn Hardcore Norwegian: Vi ser innover mot byen når himmelen blir klar. - We look inward toward the city when the sky becomes clear.

innover = inward, further into an area (focus on depth/direction).
inn = in/inside (general directional adverb, used with verbs like gå inn “go in”).
inn i + place = into (crossing a boundary), e.g., gå inn i byen “go into the city.”

Examples:

Vi ser innover mot byen = We look inward toward the city (directional; not necessarily entering).
Vi går inn i byen = We go into the city (crossing into it).
Vi går innover i skogen = We go further into the forest.

Why are both "innover" and "mot" used together? Isn’t that redundant?

Not redundant. They add different nuances:

innover describes the inward trajectory (deeper from the edge/coast/periphery).
mot sets the target/direction (“toward” a specific point).

Together (innover mot byen), they say you’re directing your gaze inwards, toward the city specifically. Without innover you lose the “inward” nuance; without mot, the target is less explicit.

What’s the difference between "mot byen" and "til byen"?

mot byen = toward the city (direction; you may not reach it). With verbs of seeing/looking, you use mot: se mot.
til byen = to the city (endpoint; you arrive there). With verbs of movement, til is common: gå/kjøre/reise til byen.

Why is it "byen" (definite) and not "by"?

Norwegian marks definiteness with a suffix.

en by = a city (indefinite singular)
byen = the city (definite singular)
byer = cities (indefinite plural)
byene = the cities (definite plural)

Here it’s specific: byen = “the city.”

Can I drop "innover" and just say "Vi ser mot byen"?

Yes. Vi ser mot byen is correct and common. You simply lose the added nuance of “inward(ly)” that innover contributes.

Why is it "når himmelen blir klar" and not "når blir himmelen klar"?

Because når introduces a subordinate (dependent) clause. In Norwegian subordinate clauses, the order is Subject–Verb: når himmelen blir klar.
Når blir himmelen klar? is a direct question (“When will the sky clear?”), which uses inversion.

Should there be a comma before "når"? Why is there none?

In the recommended (asymmetrical) comma style, you don’t put a comma when the subordinate clause comes after the main clause:

Vi ser … når himmelen blir klar. (no comma)

If you front the subordinate clause, you do use a comma:

Når himmelen blir klar, ser vi innover mot byen.

What’s the difference between "blir klar" and "er klar"?

blir klar = becomes clear (a change of state; dynamic).
er klar = is clear (a state).

So your sentence focuses on the moment the sky changes from unclear to clear.

Why is it "klar" and not "klart" or "klare"?

Predicative adjectives after er/blir agree in gender/number:

Masculine/feminine singular: klar (e.g., himmelen is masc. → blir klar)
Neuter singular: klart (e.g., været er klart)
Plural: klare (e.g., skyene er klare)

Definiteness doesn’t add -e in predicative position.

Could I use the verb "klarner" instead of "blir klar"?

Yes: når himmelen klarner = “when the sky clears.”
å klarne is a standard verb for the weather/sky clearing. Blir klar is more general and very common.

Does "når" here refer to the future even though the verb is in the present?

Yes. In time clauses with når, Norwegian often uses the present to talk about the future:

Vi drar når regnet stopper. = “We’ll leave when the rain stops.”

"Ser" vs "ser på" vs "kikker": which one should I use?

se = see / look (neutral). With directions, it takes mot: se mot byen “look toward the city.”
se på = look at, watch (focused viewing): se på byen “look at the city.”
kikke = peek/glance/look (colloquial, lighter): kikke mot byen.

Your sentence uses the directional pattern: se (innover) mot.

Does "himmelen" mean "sky" or "heaven"?

Both, depending on context. In everyday weather/astronomy contexts, himmelen = “the sky.” In religious contexts, it can mean “Heaven.” Here it clearly means “the sky.”

Can I start with the "når"-clause? What happens to word order then?

Yes:

Når himmelen blir klar, ser vi innover mot byen. When a subordinate clause comes first, the finite verb in the following main clause must still be in second position (V2): ser vi, not vi ser.

Are "mot" and "imot" the same here?

Use mot for physical direction: mot byen.
imot exists but is more old-fashioned/dialectal and is common in the sense “against” (å være imot noe). Innover mot byen is the natural choice.

Does "når" mean “when” or “whenever” here?

It can mean either; context decides. Without extra context, når can be:

single future time: “when the sky becomes clear,” or
habitual: “whenever the sky becomes clear.”

If you want to force “whenever,” add hver gang: hver gang himmelen blir klar.