Explainer | What does it mean to reach a 4 or 5 on the hurricane scale?
Hurricane intensity is classified within the Saffir-Simpson Wind Scale, which categorizes them from 1 to 5 based on sustained wind speed. Currently, Milton has just dropped from 5 to 4 on the scale. Here’s what can happen in each of the categories, according to the US National Weather Service:
– Category 1: Wind speed 119 and 152 kilometers per hour (74 to 95 miles) which is “very dangerous and causes some damage.” They usually do not damage well-built structures, but can damage wooden houses and wooden buildings. Tree branches fall. There could be power outages for days.
– Category 2: Wind speed 154 and 177 kilometers per hour (96 to 110 miles) which is “extremely dangerous and causes great damage.” Significant damage can be caused to the roofs and wall coverings of your homes. Many trees with shallow roots can fall and block roads. It can cause near total power losses with outages lasting several days and even weeks.
– Category 3: Wind speed 178 and 208 kilometers per hour (111 to 129 miles per hour) doing “catastrophic damage.” They can cause structural damage to houses and small buildings, such as the loss of roofs and gables. Roads are blocked by falling trees. There are outages of power and other services for days or weeks after the storm.
– Category 4: Wind speed 209 and 251 kilometers per hour (130 to 156 miles) doing “catastrophic damage.” Well-built homes can be severely damaged, losing most of the roof structure and/or some exterior walls. Most trees are broken or uprooted and electricity poles fall. Power outages last weeks and even months. Most of the area becomes uninhabited for weeks or months.
– Category 5: sustained winds greater than 252 kilometers per hour (more than 157 miles) which would cause “catastrophic damage” with total collapse of roofs and walls of residential and industrial buildings. Complete destruction of wooden dwellings often occurs. Trees and power poles fall and power outages last for weeks and even months. Most of the area remains uninhabited for weeks or months.