¡Está granizando!
Es-TAH gra-nee-SAN-doh
It is hailing!
Simple
Está granizando fuerte, mejor no sacar el coche.
Es-TAH gra-nee-SAN-doh FWER-teh, meh-HOR no sa-KAR el KO-cheh
It is hailing hard, better not to take the car out.
Practical advice, natural sentence
¡Menuda granizada, el granizo es enorme, va a abollar todos los coches!
meh-NOO-dah gra-nee-SAH-dah, el gra-NEE-so es eh-NOR-meh, vah ah ah-bo-YAR TOH-dos los KO-ches
What a hailstorm, the hail is enormous, it's going to dent all the cars!
menuda = what a (exclamation); abollar = to dent
More Spanish Weather Phrases