Si llueve más, me pondré el chubasquero azul para ir al mercado.

In Spanish, after si meaning if for a real future possibility, you normally use the present indicative, not the future tense.

So:

• Si llueve más, me pondré... = If it rains more, I’ll put on...

Not:

• Si lloverá más... ❌

This is a very common pattern in Spanish:

• Si tengo tiempo, iré. = If I have time, I’ll go.
• Si hace frío, me quedaré en casa. = If it’s cold, I’ll stay home.

The future idea is already expressed in me pondré.

Here más means more.

So Si llueve más means something like:

• If it rains more
• If it keeps raining more
• If it rains any harder / any more

It suggests that it is already raining, or that more rain is possible than expected. In everyday English, the most natural translation might be If it rains any more.

Ponerse means to put on when talking about clothes.

• poner = to put, place
• ponerse = to put on oneself

So:

• Me pondré el chubasquero = I’ll put on the raincoat

The me is important because it shows the action is being done to oneself.

Compare:

• Pondré el libro en la mesa. = I’ll put the book on the table.
• Me pondré el chubasquero. = I’ll put on the raincoat.

That me is the reflexive pronoun from ponerse.

Spanish often uses reflexive forms where English does not. With clothes, Spanish usually says:

• me pongo
• te pones
• se pone
• etc.

So:

• Me pondré = I will put on

Even though English does not say I will put on myself, Spanish includes the reflexive pronoun.

The verb poner is irregular in the future tense. Instead of using the full infinitive poner-, it uses the stem pondr-.

Future forms of poner:

• yo pondré
• tú pondrás
• él/ella pondrá
• nosotros pondremos
• vosotros pondréis
• ellos/ellas pondrán

This same pattern happens with some other common verbs:

• tener → tendré
• salir → saldré
• venir → vendré
• hacer → haré
• decir → diré

So me pondré is completely standard.

In Spain, chubasquero usually means a raincoat or waterproof jacket.

It is a very natural word in Peninsular Spanish. Depending on region and context, you might also hear:

• impermeable = waterproof coat / raincoat
• chaqueta impermeable = waterproof jacket

For Spanish from Spain, chubasquero sounds especially natural in an everyday sentence like this.

In Spanish, most descriptive adjectives normally come after the noun.

So:

• el chubasquero azul = the blue raincoat

This is the usual, neutral order.

Putting an adjective before the noun is possible in some cases, but it often sounds more literary, emphatic, or changes the nuance. For a simple color description, noun + color adjective is the normal pattern.

Because azul is one of the adjectives that has the same form for masculine and feminine singular.

So you get:

• el chubasquero azul
• la chaqueta azul

But in the plural it does change:

• los chubasqueros azules
• las chaquetas azules

So azul only shows number clearly in the plural, not gender in the singular.

Para often means in order to or for the purpose of. After para, Spanish commonly uses an infinitive when the subject is the same.

So:

• para ir al mercado = to go to the market / in order to go to the market

This works because the person who will put on the raincoat is also the person who will go to the market.

Compare:

• Me pondré el chubasquero para ir al mercado.
  I’ll put on the raincoat to go to the market.

But if the subject changes, Spanish often uses para que + subjunctive:

• Te doy dinero para que vayas al mercado.
  I’m giving you money so that you can go to the market.

Because a + el contracts to al in Spanish.

So:

• a + el mercado = al mercado

This is a standard contraction and you must use it.

The only common exception is when el is part of a proper name:

• Voy a El Escorial.
  Not al Escorial if you are treating El Escorial as the full place name.

But in normal cases like mercado, you use al.

Yes, but the meaning changes slightly.

• Si llueve más = If it rains more / if it rains any more
• Si llueve mucho = If it rains a lot

Más compares with an implied amount of rain already happening or expected.
Mucho just says the amount of rain is large.

So in this sentence, más suggests:

• maybe it is already raining a bit
• and if the rain increases, I’ll put on the blue raincoat

Yes. Spanish is flexible here.

You can say:

• Si llueve más, me pondré el chubasquero azul para ir al mercado.
• Me pondré el chubasquero azul para ir al mercado si llueve más.

Both are correct.

The version with Si llueve más first gives the condition first, which is very natural. It also explains why there is a comma in the original sentence.

Yes, when the conditional clause comes first, Spanish normally writes a comma before the main clause:

• Si llueve más, me pondré...

If the main clause comes first, you usually do not use a comma:

• Me pondré el chubasquero azul para ir al mercado si llueve más.

So the comma is there because the si clause is placed at the beginning.

Spanish often uses the definite article more than English does.

So ir al mercado is the normal way to say to go to the market.

In English, depending on context, you might say:

• go to the market
• go to market (less common in modern everyday speech)

In Spanish, al mercado sounds natural and complete here.

Yes, in many contexts you could say:

• Si llueve más, voy a ponerme el chubasquero azul para ir al mercado.

That uses the ir a + infinitive future, which is also very common in spoken Spanish.

The difference is mainly one of style and nuance:

• me pondré = simple future; slightly more neutral, concise, sometimes a bit more formal or definite
• voy a ponerme = near future; very common in conversation

In this sentence, me pondré is perfectly natural.