Translation of "Timely" in Spanish

If you respond in a timely fashion,

si contestan de forma oportuna:

And say a timely, polite, "No, thanks. Can't make it."

y digan un oportuno y educado: "No, gracias. No podré ir".

And we can deliver this back in a relevant timely manner for parents,

y podemos devolverle esto de forma oportuna a los padres

- A year of snow is a year of prosperity.
- A timely snow promises a good harvest.

Año de nieves, año de bienes.