[slosp]

Normally I see thunderstorms to have an updraft and a downdraught.

Here is my question, do the storms in the afternoon on a warm humid day need a downdraught or dose the whole cloud rain?

[Perito]

Thunderstorms always have updrafts and downdrafts. Those on warm, humid days are almost always of the thunderhead type. Simple rain storms don't have to have updrafts.

[FlyYakker]

You might find this Wiki input of interest. Microburst - Wikipedia, the free encyclopedia

It appears that the rain can be causal for the downdrafts.

I suspect that there is still much not understood about thunderstorms, however.

[alexweather19]

Well, initially the storms only have updrafts and no downdrafts, when they're developing. However when the storms have reached full maturity, they have both updrafts and downdrafts.