Learn Spanish (Latin America): Necesitamos la lluvia para que el clima mejore. - We need the rain so that the weather improves.

The phrase para que (so that) introduces a purpose or goal. Because the goal hasn't happened yet and isn't a guaranteed fact, Spanish always requires the subjunctive mood after para que. So, we use mejore instead of the indicative mejora.

Why can't we just use the infinitive and say para el clima mejorar?

You use para + infinitive only when the subject stays the same for both actions. But here, the subject changes from "we" (necesitamos) to "the weather" (el clima). Whenever the subject changes, you must use para que followed by a conjugated verb in the subjunctive.

Why is it el clima when the word ends in an "a"?

Words ending in -ma are often exceptions to the feminine rule because many of them come from Greek, where they were masculine. Other common masculine exceptions you have probably seen are el problema, el sistema, and el idioma.

Does para que always trigger the subjunctive?

Yes! Unlike some other Spanish connectors that can take either the indicative or the subjunctive depending on the context, para que always takes the subjunctive. This is because a purpose or goal is always an intention, never an already established fact.