The answer that fits this sentence could be hay una tormenta
Hoy llevo mi impermeable porque está lloviendo o hay una tormenta
Whose translation is:
Today, I'm wearing my raincoat because it's raining or there's a storm
The word llevo comes out from the verb llevar (to wear) and it is a conjugation of this verb in the simple present. The simple present tense (el presente or el presente de indicativo) is used to talk about habitual actions or routines. Lloviendo comes out from the gerund. The verb estar + gerund forms the progressive tense.