Heavy Weather

Heavy Weather (ヘビー・ウェザー) is the unleashed and most capable form of Weather Report, belonging to Weather Report.

Unlike the rest of Weather Report's abilities, Heavy Weather is automatic, stemming from Weather's rage against humanity. It is incredibly dangerous and nearly impossible to protect against, and only sealing the ability or killing Weather will stop the chaos it will cause.

Appearance
Heavy Weather only exists as a phenomenon that is located within the atmosphere, and therefore does not exist in a visible body.

Personality
Heavy Weather is the representation of Weather Report's hatred of humanity (prior to getting his memories taken), as it was born from his wrath.

Snail Transformation
In addition to the existing abilities of Weather Report, Heavy Weather generates various rainbows to fill a vicinity. If someone touches them, their body will morph into that of a snail. Only Weather Report is immune to the effect.

The transformation can be either a progressive change into a giant snail hybrid, a breakdown into numerous snails, or an explosion into a cluster of snail eggs that hatch immediately. One can also begin to turn into a snail by physically touching one of the snails created, or an individual already turning into a snail. All animals are affected by the metamorphosis.

A partial transformation alone comes with a number of handicaps such as getting stuck on surfaces, sluggish reactions and speed, and loss of strength because of the softening of the body. Moreover, the victims also become vulnerable to snail-eating predators and contact with salt, which dehydrates the body.

Snails created through Heavy Weather can procreate freely thanks to their ability to change gender. The procreation is very fast and accelerates exponentially, causing a rapid multiplication of the snails. Any person trapped inside a swarmed area is practically doomed to be touched at least once and begin their metamorphosis. If left unchecked, the swarm of snails will endanger whole cities.

It is eventually explained that Heavy Weather subconsciously alters the atmosphere and creates a subtle light projection with the sunlight that, if viewed, causes organisms to all think themselves as snails and forcing the transformation, like an exaggeration of ; it is unknown why it is snails specifically.

As discovered by Enrico Pucci, a blind person is immune to the effect of the Stand, since they can't see the subliminal messages carried through the sun rays. This allowed Pucci to protect himself by having Whitesnake extract his sight. Regardless, once a person starts transforming into a snail, the process is irreversible.