AUSTIN (KXAN) — Forecasting tropical systems can be extremely difficult as hurricanes can quickly steer in a different direction in the matter of a few hours.
Storm systems are primarily moved by steering currents, such as the jet stream and pressure systems.
Weaker storms can often be influenced by prevailing winds, such as trade winds. Trade winds are closer to the surface, and they steer smaller tropical waves westward off the African coast.
In the northern hemisphere, trade winds are located between 30 degrees north latitude and the equator, which is caused by the Coriolis effect.
Stronger tropical systems are often carried by winds higher off the surface, such as the jet stream, which is influenced by troughs and ridges.
This week, Hurricane Erin is being steered out to sea from several high-pressure systems, as well as a trough to the north.
The Bermuda High is one of the main reasons Erin is expected to remain out to sea.