NWS LIX - Hurricane Wind Threats and Impacts

EXTREME

Potential for wind greater than 110 mph

DEVASTATING TO CATASTROPHIC

 Potential for Extreme Impact: An extreme threat to life and property.

Hurricane winds 110 to 130 mph gusts 140+ mph:  Catastrophic damage expected to man-made and natural structures. Well constructed homes will have substantial damage to roof and walls. Destruction may occur to homes with gabled roofs, with the wind lifting them off.  

* Many industrial buildings will be destroyed; others will have partial roof and wall damage.

* High rise office buildings will sway dangerously. Most windows will be blown out and moderate structural damage is possible.  Airborne debris, including heavy pieces, will cause extensive damage.

* People, pets and livestock exposed to the winds are at great risk for injury or death.

* Electricity and water will be unavailable for days and perhaps weeks after the hurricane passes.

 * Livestock exposed to the winds will be critically injured or killed.

Hurricane winds - 130 to 160 mph gusts 170+ mph:  Devastating damage is expected. Most of the area will be uninhabitable for weeks, perhaps longer.

* At least one half of well constructed homes will have roof and wall failure. All gabled roofs will fail, leaving those homes severely damaged or destroyed.

* The majority of industrial buildings will become non functional.

* Concrete block low rise apartments will sustain major damage, including some wall and roof failure.

* High rise office and apartment buildings will sway dangerously, a few to the point of total collapse. All windows will blow out. Airborne debris will be widespread and may include heavy items such as household appliances and even light vehicles.

* The blown debris will create additional destruction. People, pets and livestock exposed to the winds will face certain death if struck.

* Power outages will last for weeks as most power poles will be down and transformers destroyed.

* Water shortages will make human suffering incredible by modern standards.

* The vast majority of native trees will be snapped or uprooted.

* Few crops will remain. Livestock left exposed to the winds will be killed.

HIGH

Potential for wind 90-110 mph

EXTENSIVE

 Potential Impacts: A critical threat to life and property from strong hurricane force winds.

Hurricane Winds 90 to 110 mph gusts 115 to 135 mph: Extremely dangerous winds will cause extensive damage and all mobile homes will be destroyed.  Houses of poor to average construction will be severely damaged or destroyed.

*Moderate to major damage will occur to well constructed homes. Many gabled roofs will fail along with some exterior walls.

* Aluminum and light steel roofs will be torn off buildings at industrial parks.

* Most windows in high rise office buildings will be blown out, with minor to moderate damage possible due to swaying. Airborne debris will cause additional major damage as well as injuries and a few fatalities.

* Near total power loss is expected with numerous lines and power poles knocked down. The availability of potable water will be diminished as filtration systems begin to fail

MODERATE

Potential for wind 60-90 mph

SIGNIFICANT

   Potential  Impacts:  A significant threat to life and property; hurricane force winds are likely

Tropical Storm winds 60 to 73 mph gusts to 95 mph:  Poorly constructed or unsecured mobile homes will be destroyed and others will have substantial damage. Houses of poor to average construction will have partial wall and roof failure as well as blown out windows.

* Unsecured light to moderate weight outdoor items will become projectiles, causing additional damage and perhaps injury.

* Many areas will have power outages with numerous downed wires and some power poles pulled down

Hurricane winds 74 to 90 mph gusts to 110 mph:  Very dangerous winds will produce widespread damage and destruction of mobile homes is likely.

* Houses of poor to average construction will have major damage, including partial wall collapse and roofs being lifted off. Well constructed houses will incur minor damage to shingles, siding and gutters as well as blown out windows. Up to one quarter of gabled roofs will fail.

* Partial roof failure is expected at industrial parks, especially to those buildings with light weight steel and aluminum coverings.

* Some glass in high rise office buildings will be blown out. Airborne debris will cause damage, injury and possible fatalities.

* Some trees will be uprooted or snapped. Nearly all large branches will snap. 

ELEVATED

Potential for wind 39-60 mph

LIMITED

  Potential  Impacts: An elevated threat to life and property; tropical storm force winds are likely.

Tropical Depression winds 30 to 38 mph gusts to 50 mph:   Minor damage may occur in older mobile home parks

Tropical Storm winds 39 to 50 mph gusts to 65 mph:  Minor damage will occur to many mobile homes. A few homes may receive mostly minor damage to roof shingles and siding.

* Unsecured lightweight items may become projectiles, causing additional damage.

* Some electrical wires will be blown down and local power outages are likely. Some weaker small trees and large branches may snap and bring down electrical lines resulting in power outages.

Tropical Storm winds 50 to 60 mph gusts to 80 mph:  Most mobile homes will experience moderate to substantial damage.

* Houses of poor to average construction will have damage to shingles, siding and gutters.

* Some windows will be blown out.

* Unfastened home items of light to moderate weight will become airborne, causing additional damage and possible injury.

* Power outages will affect entire neighborhoods, especially in areas with numerous downed trees and power lines.

LITTLE TO NONE 

Wind less than 39 mph

LITTLE TO NONE

Potential Impacts

* Wind damage not expected.   No threat to life and property.

* Winds remain below tropical storm force, but windy conditions may still be present.