Categorizing Hurricanes

Areas of low pressure mixing with a warm body of water create a recipe for tropical development and can produce episodes of thunder, wind, and rain. Sometimes isolated storm patterns meet, mix, and organize. When these storm systems display little to no recognizable patterns of wind flow, they are categorized as tropical waves.

Should the system continue to organize and create a centralized, circular wind flow pattern, the system is upgraded to a tropical depression. Once maximum sustained winds within the depression register at speeds greater than 39 mph, the system is upgraded to a tropical storm and given a name.

Tropical storms achieve hurricane status when maximum sustained wind patterns reach 74 mph. According to the Saffir-Simpson Hurricane Wind Scale, hurricanes fall into one of five categories:

• Category 1 (minimal): sustained winds between 74-95 mph
• Category 2 (moderate): 96-110 mph
• Category 3 (extensive): 111-130 mph
• Category 4 (extreme): 131-155 mph
• Category 5 (catastrophic): 156+