Cat suddenly being aggressive? ?

[Girliefriendlikesflowers]

My mums 3yo black male cat has attacked her without warning twice recently. Generally he is fairly easy going although has gone for her ankles at times in the past.

He is neutered.

Both attacks he sank his teeth in and scratched, entirely unprovoked. Is there any reason why a cat would suddenly start doing this?

If the weather is anything like here (London-ish) he could just be too hot and pissed off.

I would say because it's so hot. Cats can't regulate their temperature like us . Wait until this weather has finished and then see if he calms down and keep out of his way until then

Yeah I wondered if the hot weather would be to blame, being black he must be feeling it! !