What are Hurricanes and how do they form?published at 10:10 British Summer Time
Hurricanes are powerful storms that develop in warm tropical ocean waters. They are also known as cyclones or typhoons in other parts of the world, collectively these storms are referred to as “tropical cyclones”.
Very high wind speeds, heavy rainfall and storm surges are all typical characteristics of a tropical cyclone and hurricanes can be categorised by their peak sustained windspeed.
Major hurricanes are rated category three and above. Hurricane Milton is currently category four having reduced from a category five storm in the last few hours.
Hurricanes form as warm, moist air rises from the ocean surface and winds in the storm cloud begin to spin. The process is linked to how the Earth’s rotation affects winds in tropical regions just away from the equator.
For a hurricane to develop and keep spinning, the sea surface generally needs to be at least 27C to provide enough energy to sustain it and the winds need to not vary much with height.
If all these factors come together, an intense hurricane can form – although the exact causes of individual storms are complex.