Tropical Clouds on Parade

[Trailspotter]

This ordered cloud pattern was formed yesterday, July 26 over the tropical waters of Atlantic and can be seen on the NASA Worldview. The clouds in average are about 100 miles in diameter and their centres are about 150 miles apart, in a quasi-regular lattice.

The pattern was captured by both Terra and Aqua satellites that passed over the area about three hours apart. In that period of time it remained largely intact, but moved closer to the South America coast:

How common is such a pattern and what atmospheric processes could be responsible for its formation?
Or was it made by the breath of Godzilla that pocked its head and paw out of water at the right hand side of the top image?

 

[Henk001]

HAARP

 

[Mick West]

I think it's just convection cells. The MODIS images just happened to catch them when they were most well defined, but if you look at the the before and after images in the above loop, they are not as interesting as they seem.

Similar scale features seem very common, this is just a very nicely defined one, so it stands out.