There are several condition to form a Tropical Storm :

1. At least, having 26.5 celcius sea surface temperature on the depth of 60 m or more.

This condition would support a low-pressure area growth that on the first step would be signed as "Tropical Disturbance". Tropical Disturbance having only a slight circulation with no closed isobars around an area of low pressure. (Yes you can see a lot of Cumulonimbus and other strong convective!).

This condition would make moist Atmosphere because a lot of Evaporation and Latent heat release on the atmosphere. These latent heat would be an Energy Resource to drive the growth of Tropical Storm! These latent heat release, would make a Low-pressure areas above the Atmosphere, and yes, it will drive the wind to form the rotation wind and support the growth of Convective cloud especially Cumulonimbus.






2. At least, having 5 degree distance from the Equator. 

Have you heard Coriolis Effect? Yes, it's literally related with that! Coriolis will support the rotation of Tropical Storm. And this condition, is one of Benefit in Indonesia. Yes, Almost every region on Indonesia would be safe from these Tropical Storm possibilities. 

In physics, the Coriolis effect is a deflection of moving objects when the motion is described relative to a rotating reference frame. (en.wikipedia.com)
Coriolis Effect is pseudo-force, the only reason it appears is just the Earth Rotation. But still, although this force is Pseudo, you can't leave it, and you should calculate it, literally. And this is one of Reason why on Tropical Country, it's really hard to predict the Weather. Imagine on 0 lat, There is no Coriolis Effect, right? .... Is it ? Really? Literally zero? (A question that need to be answered)


 (http://oceanexplorer.noaa.gov)


 And this would cause :

Got it?

3. Having stable wind against altitude that will support the Growth of Thunderstorm (Thanks to the first requirment that will support this Atmosphere condition!). The more Heat on the ocean, the more stable the winds above it ! 

So, there is one Question : If Hurricanes moves north, Should it be more faster? 
Answer : Logically, yes. But still, the most important thing is SST. If hurricane moves north, it means it would loss more Energy, because the SST would be getting Colder. And it means, the Hurricanes would die soon, if it gets into the colder ones. Hurricanes would die soon, if it moves to the Continent. Why? Once again, it needs Energy that came from the Ocean. From the latent heat release, right? Of course it would die soon on continent ....

Kak (Bro).... Why did you say that Hurricanes is A Mechanism to Balance the Earth?
Dek (Sist).... Have you realized? If there's no Hurricanes, the equator would be getting warmer and warmer, while on the North, the SST are much colder. To balance it, earth needs mechanism, and Hurricane is one of the Answer! ONE OF, which means, there are a lot of phenomenon that's a part of Earth's mechanism. 

So, if the Climate Change/Global warming is real, Earth would often use these Mechanism to balance it, which means, more Hurricanes, more anomalies, and yes, More Disasters for us! So? Let's save the Earth !

Climate Change

So, what about climate change? Will this make it worst? Well, yes ! Imagine if world being warmer (which prefer to Global warming), and change the Sea Surface Temperature, which will drive more Hurricane on Tropical region. This is why we need to change our behavior for creating a better world ! Ganbatte !

So guys, maybe that's all I could explain. If you have any question and further information, you can mail me on rafi_hariri@students.itb.ac.id :) Thank you !

- Proud to be Meteorologist! -