This is the 612th most frequent Spanish word.
fuertes
"Fuertes" means "strong" in English.
In this sentence, 'fuertes' is used as an adjective to describe the intensity or strength of 'vientos' (winds).
Los vientos en la costa son muy fuertes hoy.
The winds on the coast are very strong today.
Here, 'fuertes' is applied metaphorically as an adjective to describe the compelling and persuasive nature of 'argumentos' (arguments).
Los argumentos presentados por el abogado son fuertes y convincentes.
The arguments presented by the lawyer are strong and convincing.
In this context, 'fuertes' is an adjective describing the physical sturdiness necessary for 'pilares' (pillars).