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Huricanes & Tropical Storms



What is a Hurricane?

Hurricanes are products of the interaction between the tropical ocean and the atmosphere. They are powered by heat energy from the sea and are steered by the easterly trade winds and the temperate westerlies as well as by their own energy. Around its core, winds grow with great velocity, generating violent seas. Moving ashore, they sweep the ocean inward while spawning tornadoes and producing torrential rains and floods. Each year on average, ten tropical storms (of which six become hurricanes) develop over the Atlantic Ocean, Caribbean Sea or Gulf of Mexico. Many of these remain over the ocean. However, about five hurricanes strike the United States coastline every 3 years. (from the National Weather Service)

Understanding what to look for, and what you should do before, during and after a hurricane will make you more ready to deal with their effects.


Know your Hurricane Risk

What are types of hazards associated with Tropical Storms & Hurricanes?

Storm Surge

Along the coast, storm surge is often the greatest threat to life and property from a hurricane. In the past, large death tolls have resulted from the rise of the ocean associated with many of the major hurricanes that have made landfall. Hurricane Katrina (2005) is a prime example of the damage and devastation that can be caused by surge. At least 1500 persons lost their lives during Katrina and many of those deaths occurred directly, or indirectly, as a result of storm surge.(NOAA)

Power Outage

Power Outages are one of the most common impacts from a Hurricane or Tropical Storm.  When power lines are brought down by strong winds, falling trees or debris, it may take days, weeks, or longer to get power back up and running.  CenterPoint Energy, our region's electric provider works with local communities to identify ways to speed up that time, but residents should be prepared to be without electricity for a bit of time. To view current power outages, visit their Outage Tracker map, and be sure to sign up for their Power Alert Service, which can send you a text message or call you when an outage occurs in your area. 

Rainfall Flooding

Tropical cyclones often produce widespread, torrential rains in excess of 6 inches, which may result in deadly and destructive floods. In fact, flooding is the major threat from tropical cyclones for people living inland. Flash flooding, defined as a rapid rise in water levels, can occur quickly due to intense rainfall. Longer term flooding on rivers and streams can persist for several days after the storm. When approaching water on a roadway, always remember Turn Around Don't Drown. Rainfall amounts are not directly related to the strength of tropical cyclones but rather to the speed and size of the storm, as well as the geography of the area. Slower moving and larger storms produce more rainfall. In addition, mountainous terrain enhances rainfall from a tropical cyclone. (NOAA)

Wind

The Saffir-Simpson Hurricane Wind Scale is a 1 to 5 rating based on a hurricane's sustained wind speed. This scale estimates potential property damage. Hurricanes reaching Category 3 and higher are considered major hurricanes because of their potential for significant loss of life and damage. Category 1 and 2 storms are still dangerous, however, and require preventative measures.

CategorySustained WindsTypes of Damage Due to Hurricane Winds
1 74-95 mph
64-82 kt
119-153 km/h
Very dangerous winds will produce some damage: Well-constructed frame homes could have damage to roof, shingles, vinyl siding and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles likely will result in power outages that could last a few to several days.
2 96-110 mph
83-95 kt
154-177 km/h
Extremely dangerous winds will cause extensive damage: Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected with outages that could last from several days to weeks.
3
(major)
111-129 mph
96-112 kt
178-208 km/h
Devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.
4
(major)
130-156 mph
113-136 kt
209-251 km/h
Catastrophic damage will occur: Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.
5
(major)
157 mph or higher
137 kt or higher
252 km/h or higher
Catastrophic damage will occur: A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Where can I get information on my Risk?

SRC

Houston Storm Risk Calculator

Ahead of a storm, look at what your risk level is due to storm surge, flooding, power outage and wind. When a storm is threatening Houston, see how the characteristics of the storm changes your risk. Knowing your risk ahead of time helps you better plan for what you will do when we're confronted by a tropical system.Visithoustonstormrisk.org



Hurricane Evacuation

During a hurricane evacuation, residents should be aware of the best route out of the city.  The information below will help you and your family develop an evacuation plan when the time becomes necessary.

Hurricane Evacuation Zones


Hurricane evacuations will be ordered based on your Zip Codes.  This helps you easily identify whether or not your area is affected. These evacuations are staggered to allow for a quicker movement of people.  The region has four areas, classified based on their level of threat from storm surge. Download PDF versions of the most recent Hurricane Evacuation Zone and Route Maps:

Link: 2016 Hurricane Evacuation Zone Map (LARGE) (PDF)

Link: 2016 Hurricane Evacuation Zone Map (Small-Printable) PDF
Visit HoustonHideFromTheWind.org or houstontx.gov/emergency to check for the latest status on hurricane evacuations in your area.

Assisted Evacuation

If you live in a mandatory evacuation area, and are unable to evacuate yourself, please register for the State of Texas Emergency Assistance Registry (STEAR). This confidential registry allows local emergency responders to locate you and provide you with emergency assistance during disasters such as hurricanes. For more information, call 211 (or 877-541-7905), or visit the STEAR page on our website.

Hurricane Evacuation Routes

Vehicles in Hurricane Rita Evacuation

Once you have determined whether you live in a hurricane evacuation zone, and which route you and your family should take to leave town, become familiar with the Hurricane Evacuation Contraflow.  During hurricane evacuations, at the discretion of the county Judge - inbound lanes of local freeways can be reversed to allow vehicles moving outbound to do so faster. Some lanes normally closed to regular freeway traffic are also opened to help speed evacuations, these "evaculanes" are designated with a blue circular shield on the roadway  Click the highway shield for your evacuation route to read more about the Contraflow for your chosen route. (Information provided by the Texas Department of Transportation)

Interstate 10 ShieldI-10 Between Houston and San Antonio (Evaculane)

Interstate 45 ShieldI-45 Between Houston and Dallas

US - 59 Shield US-59 Between Houston and Nacogdoches

US - 290 Shield US-290 Between Houston and Austin (Evaculane)

Have a Plan

Before a Hurricane

Stay advised of the current status of hurricanes forming in the Atlantic Ocean and the Gulf of Mexico.  You can do this by visiting the website of the National Hurricane Center or staying tuned to your local media.  As a storm approaches, be aware of hurricane evacuation procedures and orders by paying attention to local media.  When a hurricane impact is imminent, the National Weather Service for Houston/Galveston will issue warnings and watches.

  • A Hurricane Watch is issued by the National Weather Service about 48 hours prior to hurricane conditions (tropical storm force sustained winds of 38-73 mph) threatening the coastal area.  When a hurricane watch is issued for your area, you should:
    • Continue to monitor local TV or radio station for instructions
    • Check supplies, especially water (at least one gallon per person/per day for 5-7 days)
    • Fuel your vehicles and generators
    • Cover windows with plywood
    • Bring in all outdoor furniture, toys and tools
    • Moor any boats securely or move boats to a safe place.
  • A Hurricane Warning is issued by the National Weather Service when a tropical storm force sustained winds of 39-73mpg and higher, or dangerously high water and rough seas are expected within 36 hours. When a hurricane warning is issued for your area you should:
    • Monitor local Television and Radio Stations, as well as houstontx.gov/emergency for instructions
    • Move out of evacuation zones early if requested by officials
    • Check tie-downs if living in a mobile home. Leave for substantial shelter
    • If not in the evacuation zones: review and verify your emergency plan checklist(s) are complete.
    • Fill bathtubs and all available containers with extra water
    • Turn off utilities if requested
    • Stay away from windows, doors and openings
  • A Storm Surge Watch is issued by the National Weather Service when the possibility exists for life-threatening coastal flooding from a tropical storm, hurricane or post-tropical cyclone from rising water moving inland from the shoreline into an area is expected within 48 hours.
    • The watch may be issued earlier when other conditions, such as the onset of tropical-storm-force winds, are expected to limit the time available to take protective actions for surge (e.g., evacuations).
    • The watch may also be issued for locations not expected to receive life-threatening inundation, but which could potentially be isolated by inundation in adjacent areas.
  • A Storm Surge Warning by the National Weather Service when the possibility exists for life-threatening coastal flooding from a tropical storm, hurricane or post-tropical cyclone from rising water moving inland from the shoreline into an area is expected within 36 hours. 
    • The warning may be issued earlier when other conditions, such as the onset of tropical-storm-force winds, are expected to limit the time available to take protective actions for surge (e.g., evacuations).
    • The warning may also be issued for locations not expected to receive life-threatening inundation, but which could potentially be isolated by inundation in adjacent areas.

Do I Need to Evacuate?

Most people in the City of Houston do not need to evacuate during a hurricane.  The City encourages those who live in storm surge areas, require electricity for medical purposes, or live in mobile homes to evacuate ahead of a storm. Evacuation orders will be issued for storm surge areas by ZIP Code.  Find out if you live in an evacuation zone, and get real-time information on evacuation from the Houston Hide From the Wind website.

Remember, that after a hurricane or tropical storm, especially one that generates a lot of rain, it may be necessary to evacuate areas around streams, creeks, rivers and bayous.  Be prepared to evacuate and to shelter in place, depending on the situation.  Stay tuned to local information sources (such as Radio and TV), including houstontx.gov/emergency to find out about evacuation orders in your neighborhood.


If you are ordered to evacuate, do so as quickly as possible.

During a Hurricane

  • Remain indoors in an interior hallway, bathroom or closet on the lowest level of your home well away from windows
  • Cover yourself and family members with a mattress or seek shelter under something sturdy, such as a well constructed dining room table, which could protect your from possible debris.

After a Hurricane

  • Beware of unsafe food and/or water.  Boil tap water before drinking unless you are told it is unnecessary.
  • Utilities could be cut off. Treat all downed lines as live wires and don't approach or touch them. If you smell gas, leave the area immediately and notify the proper authorities from a safe area
  • Make temporary repairs, without taking unnecessary risk, to protect your property from further damage
  • Inform your insurance agent of any damage, and leave word where you can be reached. Take pictures of damage.

Have a Hurricane Kit

Having basic supplies ahead of time will give you peace of mind and help make sure your family has what it needs if a quick-onset storm happens. The City of Houston recommends people have to kinds of emergency kits:  a Go-Kit and Stay-At-Home kit.

Go-Kit

Your go-kit should be used for emergencies where you might have to quickly evacuate or shelter in place.  Supplies in a go-kit are intended to help people survive the first 24-72 hours in an evacuation or shelter-in-place situation.

Your go-kit should contain:

  • Copies of your important papers in a waterproof bag.
  • Extra set of car and house keys.
  • Extra mobile phone charger.
  • Bottled water and snacks such as energy or granola bars.
  • First-aid supplies, flashlight, and whistle.
  • Battery-powered or hand-crank radio (with extra batteries, if needed).
  • A list of the medications each member of your family needs and at least a 14-day supply of each medication.
  • Toothpaste, toothbrushes, wet cleansing wipes, and so on.
  • Contact and meeting place information for your family and a map of your local area.
  • A stuffed animal or toy for your child and something to help occupy their time, like books or coloring books. If this includes a hand-held video game, make sure you have extra batteries.
  • Rain ponchos.
  • External mobile phone battery pack or solar charger. Some hand-crank flashlights will also include a phone charger

Special Considerations

  • Always to remember that no two families are alike.  If you have infants or very young children, or if you are elderly or disabled, you may have additional items that you need everyday that should be in your go kit.

Stay-at-Home Kit

There may be situations where you need to stay in your home for a period of time.  This includes riding out a hurricane.

Special Considerations

  • Water (one gallon per person per day, for drinking and sanitation—up to a 7-day supply).
  • Non-perishable food (up to a 7-day supply per person).
  • Battery-powered radio (with extra batteries) or hand-crank radio.
  • Weather radio with tone alert and extra batteries.
  • Flashlight and extra batteries.
  • First-aid supplies.
  • Whistle to signal for help.
  • Filter mask or cotton t-shirt, to help filter the air.
  • Moist towelettes, garbage bags, soap, disinfectant, and plastic ties for personal sanitation.
  • Wrench or pliers to turn off utilities (water and electric).
    • Manual can opener if your kit contains canned food.
    • Plastic sheeting and duct tape to shelter-in-place (see pages 26-27).
    • Plastic tarps for emergency roof repair.
    • Items for unique family needs, such as daily prescription medications, infant formula, or diapers.
    • Mess kits, paper cups, plates, and plastic utensils.
    • Cash and change.
    • Paper towels.
    • Fire extinguisher.
    • Matches in a waterproof container.
    • Rain gear, sturdy shoes, long pants, and gloves.
    • Important family documents such as copies of insurance policies, identification, birth certificates, passports, and bank account records in a waterproof, portable container.
    • A stuffed animal or toy for your child and something to help occupy their time, like books or coloring books. If this includes a hand-held video game, make sure you have extra batteries.

Staying Informed

Radio, TV, Internet

Look for information on local Radio and Television stations. The City of Houston and regional response agencies work closely with local media on a year-round basis to ensure that information quickly flows to Houstonians through local media.  Also, be sure to visit official internet sites for information to make sure you are getting the most accurate information from local officials. Suggestions include:

Social Media

Be sure to follow official social media channels when hurricanes are threatening our area.

Emergency Notification Systems

AlertHouston
AlertHouston is the City's official emergency notification system.  Opt-in at houstontx.gov/emergency to receive email messages about ongoing threats, as well as information about changing conditions and recommendations to stay safe.  You can also follow AlertHouston on Twitter (@AlertHouston) and Facebook to stay up to date. 

Greater Harris County 911 Emergency Notification System (ENS)
In addition to the City's AlertHouston service, the Greater Harris County 911 Emergency Communication Network provides reverse 911 service to people living in Harris and Fort Bend Counties, including Houston residents.  This system is used for neighborhood-level emergencies such as hazardous chemical releases, missing children, evacuations and shelter-in-place orders.  Register online at 911.org.

Wireless Emergency Alerts (WEA)