I see that probably in Ras Laffan area is where the cloud particles develop earlier. Precipitation distribution depends on where the clouds condensing making it heavy so the water droplets fall back to the ground. "Precipitation forms when cloud droplets (or ice particles) in clouds grow and combine to become so large that the updrafts in the clouds can no longer support them, and they fall to the ground. The more water vapor there is below the cloud, and the stronger the updrafts that cause this water vapor to condense into cloud water or ice particles, the more likely it is that precipitation will form within the cloud."

http://www.weatherquestions.com/What_causes_precipitation.htm