Welcome to the forum! Vaguada: trough, an elongated region of relatively low atmospheric pressure, often associated with a front.
(Thanks, Wikipedia)
I've heard "trough" in this context tons of times.
Other translations of "trough":
(container — for water) abrevadero m, bebedero m;
(— for feed) comedero m
(on land, seabed) hoya f, depresión f
(Meteo): a ~ of low pressure una depresión, una zona de bajas presiones
You're welcome!
But you can't close a post with "greetings." It's not like "saludos" but like "hello" -- an opening remark, a greeting. I suggest "regards." In England they say "cheers."
I know this is an old thread but I wonder whether there is really that much difference between a trough, a low pressure system or simply a depression.
Look at this taken from today's mountain forecast from aemet.es
"SITUACION GENERAL:
NIVELES MEDIOS Y ALTOS: BAJA AL OESTE DE IRLANDA CON UNA VAGUADA
ROZANDO EL NOROESTE PENINSULAR. LA BAJA ESTA BLOQUEADA POR UNA
DORSAL SOBRE EUROPA QUE SE EXTIENDE DESDE AFRICA Y BALEARES."
In other words there's a low to the west of Ireland. Would front be a good translation for the vaguada sweeping the NW of Spain?