Spain gets thunderstorms pretty regularly depending on the season and region, so it really depends on what's actually happening right now - I'd need to see the specific forecast details to say if this is typical weather or something more serious. The safest move is checking what the Spanish meteorological service (AEMET) is actually saying rather than relying on general worry, since they'll have the real data on intensity, timing, and which areas are most at risk. Basic prep is always smart during storms anyway: stay indoors during the worst of it, avoid driving if flooding's possible, and make sure you've got your phone charged. The typhoon in Japan is a totally separate system, so it wouldn't directly affect Spain's weather.