What is the auxiliary verb does or is of weather?

There is no substantive verb in what is the weather, so there is no need for the auxiliary verb does, so use the be verb and the be verb. Adjectives or nouns are added after them, using the simple present tense.

The specific difference between is and does lies in:

1 has different meanings: is and does have different meanings when they are corresponding verbs.

Is interpretation: v. can be understood as yes (the third person singular of be is usually the present tense)

Does interpretation: V. Auxiliary verbs with no practical meaning (third person singular form of verb do)

Second, the usage is different: there are differences in sentence collocation

Is usage: is is a be verb, which is used with v-ing to form the present continuous tense and with v-ed to form the passive voice. When used as an auxiliary verb, it can be used with the present participle of the verb to form the progressive tense, and it can also be used with the past participle of the transitive verb to form the passive structure.

The weather is very good today. The weather is very good today.

Does usage: used to form the interrogative or negative forms of the simple present tense and the simple past tense, followed by the prototype verb (entity verb). In question? Do has no specific meaning, but it is grammatically necessary.

He doesn't like the smell. He doesn't like the smell.

Extended data

The role of English auxiliary verbs in assisting the completion of active words;

He is singing. He is singing. He's married. He's married.

He was sent to England. He was sent to England.

Form a question, such as: Do you like college life? Do you like college life?

I don't like him. I don't like him.

Be sure to come to the party tomorrow night. Be sure to come to the party tomorrow night.

References:

Baidu encyclopedia-English auxiliary verbs