Question : In Brasilia during the raining season it often starts sunny and hot in the morning, but begins changing at around mid-day. The wind picks up. Clouds appear as if from no-where. The weather turns cold. And suddenly it's raining heavily.
Right now, in London, we're seeing the same thing. Gloriously sunny mornings ... that suddenly turn. Cool breeze, clouds out of nowhere ... maybe rain. At mid-day.
My question : Brasilia is almost 1000km from the sea. And further from the Amazon basin where a lot of the water comes from. London is only thirty or so miles from the sea. Presumably water that evaporates from the sea (or Amazon) takes a very different amount of time to form into clouds and find its way to London or Brasilia.
So why the similarity of this pattern? Is it coincidence? Is it that the clouds are not "pre-formed" water carriers, but actually spontaneously form over Brasilia and London for the same reasons in response to the same conditions at around mid-day?