We hear terms like “a Category 3 hurricane” or “a level 2 severe weather alert,” but what do these terms mean? Here is a simple guide to staying safe by understanding these hurricane and severe weather ratings.
The Storm Prediction Center (SPC), a division of the National Weather Service (NWS), assesses the risk of severe weather and places them into 5 different category ratings from 1 to 5, from low to high.
Level 1 (Marginal Risk): Isolated severe storms. Heavy rain, winds and hail her main threats. Limited in duration, coverage and intensity.
Level 2 (Slight Risk): Scattered severe storms. Damaging winds, 1″-2″ hail, 1-2 tornadoes. Not widespread, isolated intense storms, short-lived.
Level 3 (Enhanced Risk): Numerous severe storms. Likely wind damage, 1″-2″ hail, several tornadoes, widespread, a few intense storms, more persistent.
Level 4 (Moderate Risk): Widespread severe storms. Widespread wind damage, destructive hail, strong tornadoes, widespread severe storms and long-lived intense storms.
Level 5 (High-Risk): Widespread and long-lived destructive storms, catastrophic hail, tornado outbreak or derecho, widespread, long-lived destructive storms.
Hurricane category numbers are based on the Saffir-Simpson Hurricane Wind Scale, which gives a 1 to 5 rating based on a hurricane’s maximum sustained wind speed, according to the NOAA. Keep in mind that this scale only looks at the wind and potential property damage. This scale does not consider the further damage that could be incurred from hazards such as storm surge, rainfall, flooding, and tornadoes.
Category 1: Winds between 74-95 MPH. Very dangerous winds that will produce some damage. Well-constructed homes could have roof and siding damage. Shallow rooted trees could be toppled. Extensive damage to power lines and poles.
Category 2: Winds between 96-110 MPH. Extremely dangerous winds that will cause extensive damage. Well-constructed homes could have major roof and siding damage. Many trees could be toppled. Near-total power loss with outages from several days to weeks.
Category 3 (major): Winds between 111-129 MPH. Devastating damage will occur. Well-constructed homes could sustain severe damage. Many trees downed, roads blocked. Electricity and water unavailable for days to weeks.
Category 4 (major): Winds between 130-156 MPH. Catastrophic damage will occur. Well-constructed homes could have major damage. Most trees could be toppled. Power outages from weeks to months. Most of the area uninhabitable for weeks or months.
Category 5 (major): Winds between 157 MPH or higher. Catastrophic damage will occur. High percentage of homes could be destroyed. Trees and power poles toppled isolating residential areas. Power outages from weeks to months. Most of the area uninhabitable for weeks or months.