أصبح الطقس باردا.

أصبح is a verb meaning to become or to turn into. In this sentence, it links the subject الطقس with its new state باردا.

So the structure is:

• أصبح = became
• الطقس = the weather
• باردا = cold

A very important grammar point: verbs like أصبح belong to a group that often take:

• a subject (اسم أصبح) → here: الطقس
• a predicate or resulting state (خبر أصبح) → here: باردا

So the sentence is describing a change of state: the weather became cold.

Because باردا is in the accusative case.

After أصبح, the subject stays in the nominative case, but the predicate of أصبح is usually in the accusative case.

So:

• الطقسُ = nominative subject
• باردًا = accusative predicate

In fully vowelled Arabic, you would write:

أصبحَ الطقسُ باردًا

In everyday unvowelled writing, the final case ending is often not written, so you may just see باردا.

الـ is the Arabic definite article, equivalent to the in English.

So:

• طقس = weather / a weather condition
• الطقس = the weather

In this sentence, Arabic uses the definite form because it is talking about the weather in a general or specific sense, just as English does.

Arabic often does not need a separate subject pronoun when the noun itself is stated.

In English, you might say:

• The weather became cold

You do not need it there because the weather is already the subject.

Arabic works the same way here:

• الطقس is the subject
• so no extra pronoun is needed

Arabic also often builds complete sentences without words that English requires, especially in simple descriptive sentences.

Yes, that is possible.

Both of these are correct:

• أصبح الطقس باردا
• الطقس أصبح باردا

The difference is mainly one of style, emphasis, and sentence type:

• أصبح الطقس باردا starts with the verb, so it is a verbal sentence
• الطقس أصبح باردا starts with the noun, so it feels more like a nominal-style sentence with a verb following

In MSA, starting with the verb is very common and natural.

It is pronounced approximately aṣbaḥa.

A rough breakdown:

• أَ = a
• ص = an emphatic s
• بَ = ba
• حَ = a breathy ḥa, pronounced deep in the throat

So: aṣ-ba-ḥa

Two sounds may be unfamiliar:

• ص is not the same as plain س; it is heavier or darker
• ح is not the English h; it is a stronger voiceless throat sound

Here باردا is not just a simple adjective modifying a noun inside a noun phrase. It is functioning as the predicate of the sentence.

Compare:

• الطقس البارد = the cold weather
  Here البارد is an adjective directly describing الطقس

But in your sentence:

• أصبح الطقس باردا = The weather became cold

Here باردا tells us the state that the subject came to be in after the action of أصبح.

So grammatically, it is better to think of it as a predicate adjective.

Because predicate adjectives in Arabic usually do not take الـ in this kind of sentence.

Compare:

1. Adjective inside a noun phrase

   • الطقس البارد = the cold weather
   • both words are definite

2. Predicate after a subject

   • الطقس بارد = the weather is cold
   • بارد does not take الـ

Your sentence follows the second pattern, except it uses أصبح:

• أصبح الطقس باردا

So باردا is indefinite in form, even though it refers to the state of a definite noun.

In full formal vocalization, the sentence is:

أصبحَ الطقسُ باردًا

The endings are:

• أصبحَ → final fatḥa on the past-tense verb
• الطقسُ → ḍamma, because it is the subject of أصبح
• باردًا → fatḥa + tanwīn, because it is the predicate of أصبح and therefore accusative

Learners often see Arabic without these endings written, but understanding them helps a lot with grammar.

Not always.

Historically and in some contexts, أصبح can relate to morning or mean to enter the morning. But in very common modern usage, it also means to become.

So depending on context, أصبح can mean:

• he entered the morning / was in the morning
• he became

In your sentence, it clearly means became, because it is followed by a subject and a predicate describing a new state:

• أصبح الطقس باردا = the weather became cold

Yes. صار is another very common verb meaning became.

So this would also be correct:

• صار الطقس باردا

Both أصبح and صار can express change of state, though there can be small differences in tone or usage depending on context and style. For many learners, both are worth recognizing as verbs that often behave similarly in grammar:

• subject in the nominative
• predicate in the accusative

So:

• أصبحَ الطقسُ باردًا
• صارَ الطقسُ باردًا

Both are grammatically natural.