Air Masses

There is a large maritime polar air mass sweeping from the Atlantic ocean that directly affects Madagascar. The inter tropical convergence zone during the summer shifts from being located over northern Madagascar to the southern region.
This map shows all of the airmasses worldwide. You can see the Maritime Polar mass that moves up towards Madagascar

Source: Earthmyspace.com
This photo shows you the Inter Tropical Convergence Zone (ITCZ)over Madagascar

Source: web.idrc.ca
The steep topography of southern Madagascar causes cool moist air masses to rise and produce rainfall. Ranohira is not that steep however i still receives a fair amount of precipitation.
Here is a map that illustrates the variety of topography in Madagascar

Source: Mapsof.net
From my previous blog post you can compare the elevation of Ranohira with other parts of Madagascar.
During the winter mid-lattitude storms pass through southern Madagascar. Cyclones form over the Indian ocean and move inland towards the south and west. Here is a map tracking the patterns of these cyclones. This map doesn't track any of the cyclones heading south towards Ranohira, however, depending on environmental factors these storms could affect Ranohira and cause great damage.

Source: scienceblogs.com
This is a picture i found interesting. Its and arial view taken by a Nasa earth observatory of a cyclone moving towards Madagascar.

Source:earthobservatory.nasa.gov

ALSO! Sorry for all of my photos being so gigantic, i couldn't figure out how to shrink them.