ELMIRA, N.Y (WETM)- As Hurricane Ian made landfall in Florida today as a strong Category 4 Hurricane, it was just 2 miles per hour away from being classified a Category 5, the highest rating. But how are hurricanes rated?

Hurricanes are rated by using the maximum sustained wind speeds. This is derived from the Saffir Simpson Hurricane Wind Scale which rates the from categories 1-5. The scale is as follows:

Category 1: 74 to 95 miles per hour

Category 2: 96 to 110 miles per hour

Category 3: 111 to 129 miles per hour

Category 4: 130 to 156 miles per hour

Category 5: 157+ miles per hour

Something you also hear mention is storm surge when dealing with hurricanes. Some areas on the Florida coast have the possibility of seeing up to 12-18 feet of storm surge, but what is it?

Storm Surge is defined by the National Hurricane Center (NHC) as the abnormal rise in the seawater levels during a tropical storm. It is measured as the height of the water over and above the levels predicted by the astronomical tide. But the NHC also notes since it is the difference between water levels it does not have a standard reference level.

Now we can talk about what causes storm surge. Storm surge is caused by the winds of the storm pushing water onto the shore. The level of storm surge depends on many factors such as the orientation of the storm to land, the strength, rating, size, and speed of the storm. But overall, the general rule of thumb is the highest surge occurs with the strongest hurricane winds.

It is considered dangerous because it can rise rapidly. It can rise several feet in just several minutes. The storm surge also typically moves at the speed of the storm and the storm surge is very powerful and heavy in weight as well. Debris is typically in the water as well and the storm surge can contain floating debris that can cause damage if you are caught in the surge.