Learn Hardcore Portuguese (Brazil): Mesmo com chuva, meu vizinho quer fazer a reunião ao ar livre. - Even with rain, my neighbor wants to hold the meeting outdoors.

The phrase mesmo com literally means “even with.” Here, mesmo serves as an adverb meaning “even” (or “still”), and com is the preposition “with.” Together they introduce a condition that doesn’t stop the action: “even with rain.”

What’s the difference between mesmo com chuva and apesar da chuva?

Both express “despite the rain,” but there are subtle style and structure differences:

mesmo com chuva is a noun-phrase construction (“even with rain”) and often sounds more conversational.
apesar da chuva uses the conjunction apesar de
- definite article + noun (“despite the rain”) and is slightly more formal.
  In most contexts you can use either without changing the basic meaning.

Why isn’t there an article before chuva, as in com a chuva?

When you talk about weather phenomena in a general sense, Portuguese usually drops the article. You say “com chuva” (with rain), “com sol” (with sun), “com vento” (with wind). Adding an article (“com a chuva”) would make it feel like you’re referring to a specific rain event, which is less common in everyday speech.

Why not use mesmo que chova here instead of mesmo com chuva?

mesmo que chova is a full subordinate clause introduced by mesmo que (“even if”), which requires the subjunctive verb chova (from chover). It emphasizes a hypothetical or uncertain action: “even if it rains.”
mesmo com chuva is a noun phrase focusing on the current fact of rain (“even with rain”).
Both are grammatically correct, but the original choice highlights the existing condition rather than a hypothetical one.

In quer fazer a reunião, why do we use fazer a reunião and not marcar a reunião or ter a reunião?

fazer a reunião literally means “to make/hold the meeting,” and it’s an idiomatic way to say “to conduct a meeting.”
marcar a reunião means “to schedule/arrange the meeting,” focusing on setting a time.
ter a reunião could mean “to have the meeting,” but it’s less common in Portuguese; you’ll hear ter reunião without an article in casual speech or corporate slang.
So fazer a reunião is the most natural choice when you mean “to carry out the meeting.”

What does ao ar livre literally mean and how does the contraction ao work?

ar livre means “open air.”
ao is the contraction of the preposition a (“to”/“at”) + the masculine definite article o (“the”).
Together ao ar livre literally means “to the open air,” and idiomatically “outdoors.”

Could we rephrase ao ar livre with another phrase like fora de casa or na rua, and would it be the same?

You can, but the nuance changes:

fora de casa (“outside the house”) stresses being outside your home—not necessarily outdoors in a park or garden.
na rua (“on the street”) implies a public street setting.
ao ar livre is the general, idiomatic way to say “in the open air” without specifying street, house, etc.
Choose based on the exact setting you want to describe.