Fa fred, així que porto una jaqueta.

In Catalan, fa fred is the normal way to say it is cold about the weather.

Here fer is used in an impersonal weather expression:

• fa fred = it’s cold
• fa calor = it’s hot
• fa vent = it’s windy

By contrast, és fred usually describes something or someone as cold by nature or quality:

• L’aigua és freda = The water is cold
• És una persona freda = He/She is a cold person

So for general weather, fa fred is the natural choice.

You would normally say tinc fred.

That is an important difference:

• Fa fred = It’s cold
• Tinc fred = I’m cold

Catalan often uses tenir for physical sensations:

• tinc gana = I’m hungry
• tinc set = I’m thirsty
• tinc son = I’m sleepy

So fa fred talks about the weather, while tinc fred talks about how you feel.

Catalan usually drops subject pronouns when they are not needed, because the verb ending already shows who the subject is.

• porto = I wear / I’m wearing / I carry
• portes = you wear / you’re wearing / you carry
• porta = he/she wears

So porto una jaqueta already clearly means I’m wearing/carrying a jacket.

You can add jo for emphasis:

• Jo porto una jaqueta = I’m the one wearing a jacket

But in a neutral sentence, leaving out jo is more natural.

Because portar and posar-se do not mean exactly the same thing.

• porto una jaqueta = I’m wearing a jacket / I have a jacket on
• em poso una jaqueta = I’m putting on a jacket

So:

• porto focuses on the state/result: the jacket is on me
• em poso focuses on the action of putting it on

In this sentence, the idea is that because it’s cold, the speaker is wearing a jacket, so porto fits well.

Not always. Portar can mean both to wear and to carry.

So porto una jaqueta could mean:

• I’m wearing a jacket
• I’m carrying a jacket

Usually the context makes it clear. In a sentence about cold weather, most people will understand I’m wearing a jacket.

If you want to be extra clear, Catalan can specify:

• porto posada una jaqueta = I’m wearing a jacket
• porto una jaqueta a la mà = I’m carrying a jacket in my hand

Així que means so, therefore, or so then.

It links the two ideas:

• Fa fred = It’s cold
• així que porto una jaqueta = so I’m wearing a jacket

It introduces a result or consequence.

Other possible connectors are:

• per això = because of that / that’s why
• per tant = therefore
• doncs = so / then / well

But així que is a very natural, common choice here.

Catalan often uses the simple present where English uses a continuous form.

So:

• porto una jaqueta can mean I wear a jacket or I’m wearing a jacket

In this sentence, Catalan does not need a special progressive form to express the current situation.

A form like estic portant exists grammatically, but here it sounds unnatural. Portar in the sense of wearing is usually expressed with the simple present:

• Avui porto una jaqueta = Today I’m wearing a jacket

So porto is the normal choice.

The comma separates two clauses:

• Fa fred
• així que porto una jaqueta

This is similar to English punctuation in sentences like:

• It’s cold, so I’m wearing a jacket.

With connectors such as així que, a comma is very common and helps readability. In short, the comma marks a pause and shows that the second part is the consequence of the first.

Because jaqueta is a singular countable noun, and Catalan normally needs an article or determiner with nouns like this.

So:

• porto una jaqueta = I’m wearing a jacket

Without una, the sentence would usually sound incomplete or unnatural in standard Catalan.

This is similar to English, where you normally say a jacket, not just I’m wearing jacket.

Yes. A very common alternative is:

• Porto una jaqueta perquè fa fred.

That means I’m wearing a jacket because it’s cold.

The difference is mainly in how the relationship is presented:

• Fa fred, així que porto una jaqueta = It’s cold, so I’m wearing a jacket
• Porto una jaqueta perquè fa fred = I’m wearing a jacket because it’s cold

Both are natural. One presents the cause first, and the other presents the result first.

Another common option is:

• Com que fa fred, porto una jaqueta. = Since it’s cold, I’m wearing a jacket.

Així is pronounced roughly like eye-SHEE or uh-SHEE, depending on the dialect.

A couple of useful points:

• the x here sounds like sh
• the accent on í shows that the stress falls on that syllable

So the important thing is that the word ends with a stressed -í sound.

You do not need to reproduce every regional pronunciation perfectly at first; the key is recognizing that així que is a common expression meaning so / therefore.