fire risk, have a Google search
Last year, when it got to 39C here, the dewpoint was 10C, which works out as around 19% humidity. That was enough for several grass fires to break out, and it badly affected some trees, too: the leaves shrivelled and curled up on the neighbour's cherry tree, for example, and it didn't recover last year - thankfully this year it's sprouting new leaves. Similarly the hazel lost a lot of its leaves due to the stress.
What we're seeing forecast for Seville is even more severe than that, and it literally turns the environment into a tinderbox.