- Education and Science»
- Geography, Nature & Weather
The Dangers of Ice Storms
An ice storm is a type of winter storm caused by freezing rain. The U.S. National Weather Service (NWS) defines an ice storm as “a storm which results in the accumulation of at least 0.25-inch (6.35 mm) of more of ice on exposed surfaces.” Ice storms are the end result of a particular convergence of meteorological factors that form during the colder periods of the year.
When falling rain comes into contact with a freezing surface (32° F/0° C), the rain freezes and turns into ice on contact. The resulting ice then covers most exposed surfaces in varying levels of heavy ice. The additional weight of the ice can break tree branches—or cause entire trees to fall over—and can affect power and telephone lines. What’s more, ice-covered surfaces such as roadways can result in other particularly dangerous traffic hazards.
Ice storms are classified by their structural damage or by the approximate accumulation of 0.25 inches (6.35 millimeters) or more of ice. A minor glaze of ice tends to create hazardous conditions for both traffic and pedestrians. But the actual severity of full-fledged ice storms are seen in full effect by the extensive power outages, halted air and ground transportation, and considerable property damage.
The severity of damage increases with greater accumulations of ice. Accumulations between ¼ and ½ inch (0.625 and 1.25 cm) can cause small branches and weak limbs to break and ½ inch (1.25 cm) or greater of ice can cause large branches to break. And the greater the amounts of ice, the greater the damage—and danger—to affected areas.
Even a thin coating of ice can create multiple levels of havoc for the affected area(s). And the resulting damage often affects areas on various levels.
The weight of the ice can cause tree branches to break, bringing them partially (or fully) down on vehicles and other property. In the most severe cases, even homes can be damaged from fallen tree and branches weighed down by ice. In fact, accumulated ice can increase the weight of tree branches by 30 times, making fallen branches all but a certainty in even the most (relatively) modest of ice storms. The result is often widespread and extended power outages resulting from the accumulation of ice on both trees and electric power lines, brought down by the additional weight. For this reason, damaged trees are the single greatest cause of power outages during ice storms.
Quite often during even moderately ice storms, electrical power lines are the first exposed objects to suffer damage. Downed live power lines, snapped from poles from the weight of ice can create an electrocution hazard for those who may inadvertently touch them. In addition, nearby tree branches made heavy by ice can easily snap, and bring down even more power and utility lines (and create widespread damage as they fall on vehicles and other property). But even without falling trees and tree branches, the weight of the ice itself can easily snap power lines and also break and bring down power lines and any attached utility poles. The same is true electricity pylons with steel frames.
Despite the high construction and maintenance standards of the electrical infrastructure in the U.S., the type of damage an ice storm can inflict on these infrastructures can leave people without power for anywhere from several days to a month. For example, in the U.S., most electrical distribution lines are designed to withstand up to ½ inch (12.7 millimeters) of ice on their surfaces, of ice and 40-mph (63 kph)winds. But according to most meteorologists, just one quarter of an inch (6.35 mm) of ice accumulation can add about 500 pounds (230 kilograms) of weight per line span. Any incurred damage from such a strain on these systems is easily capable of effecting down a large metropolitan area.
Other damage and effects
In the most severe ice storms, resulting power and utility outages can last for weeks as hazardous weather conditions linger—hindering both repairs and recovery for affected areas. Consequently, ice storms can also disrupt communication for extended periods of time should cell phone and/or communications towers become damaged due to excessive ice. But the potential damage and disruptions caused by an impending ice storm can vary—particularly insomuch as attempting to provide the public with accurate warnings about an impending ice storm event.
Another, less well-aware hazard stemming indirectly from the loss of electrical power during ice storms is the danger of suffocation due to the threat of carbon monoxide (CO) poisoning. The relatively high incidence of CO poisoning during ice storms occurs due to the use of alternative methods of heating and cooking during prolonged power outages, which is most common after severe ice storms. Gas generators, charcoal and propane barbecues, and kerosene heaters contribute to CO poisoning when they operate in confined locations. In much the same way, fires can also result from accidental misuse of these alternative heating sources.
Ice storms are a particular hazard to aviation. The accumulation of ice can damage exposed aircraft. Additionally, if freezing rain droplets on the surface of airplane wings are left intact, they could freeze during a plane’s flight at high altitudes, causing ice to accumulate in clouds on the wings. Accumulated ice (or ice-damage) on an airplane’s wings can interfere with the flight dynamics of the aircraft, causing it to crash. It is for this reason that is all major airports have mandatory deicing procedures in cold weather.
The surfaces of roadways can become nearly impossible to travel across during ice storms. Indeed, driving during and immediately after an ice storm is extremely hazardous due to the lack of traction that ice-coated streets creates. This can cause vehicles to skid out of control, leading to devastating single or even multi-vehicle crashes—that could prove fatal. During freezing rain or ice storms, bridges and overpasses have a tendency to freeze before other types of surfaces, and thus increasing the risk for those forced to travel during ice storms. Because the majority of ice storm deaths are due to accidents
Finally, building infrastructures are vulnerable to ice storms as well. Pipes can freeze and burst in poorly-insulated and/or constructed dwellings. Roofs and other vulnerable sections of homes can be damaged if struck by ice-weighted trees or tree branches. The same is true for parked automobiles. Insured property losses from ice storm damage in the U.S. averages at least 300 million dollars annually.
Private property (along with aspects of public infrastructure) is most vulnerable to damage resulting from ice storms. What’s more, this damage can occur in several different ways—and property owners need to be aware of the different ways that ice can damage property. As such, there are several options property owners have at their disposal to help minimize the amount of potential ice storm damage. But many of these require preparations prior to the start of colder, ice-storm producing weather setting in.
Trees pose several direct and indirect ice storms hazards. Problems arise when icy precipitation accumulates on the surfaces of trees. When this precipitation accumulates and freezes, it adds additional weight to trees, weighing down their branches and often causing them to crack and fall. In worst-case scenarios, ice-damaged tree limbs can fall on buildings (including homes) and automobiles, causing extensive damage. They can also become entangled in power and utility lines as they fall, bringing them down as well with their added weight. And the trees themselves are often damaged, sometimes to the point where they are weakened—causing them eventually topple-over, immediately or over a varying period of time afterwards.
For this reason, trees that grow closest to homes or other types of dwellings should be trimmed. Branches that hang directly over homes should be cut. Focus should be given to pruning out not only limbs that have grown directly over property, but also dead limbs that are usually the first to snap off (dead, rotted, and brittle wood has little strength, and thus, is usually the first to break off under the additional weight of ice).
Valued plants should be protected from possible ice damage when the weather forecast calls for an imminent ice storm. And one of the most effective methods for protecting small plants and shrubs is to cover them with a waterproof tarp (most commercially-sold waterproof tarps are made up polyethylene materials).
Take precautions to minimize freezing of walkways around property. It’s a good idea to dispense salt, sand, or deicing pellets on and around walkways to prevent ice from forming on their surfaces and becoming an injury hazard.
Take care to make provisions for any pets, as they are just as vulnerable to the hazards of cold weather as humans. Those with family pets might—in all likelihood—opt to keep them indoors before and during an ice storm. However, that same option may not be available for all domesticated animals. For those with farms, livestock and other animals should be promptly moved into a sheltered area such as a barn. In lieu of this, a partially-sheltered area stocked with ample amounts of hay (for both food and warmth) or some other form of bedding.
There is always a chance that power and (as a result) heat can be disrupted during an ice storm, particularly during an intense one. For this reason, it is advantageous to prepare ahead of time for this and other related possibilities.
First and foremost, for anyone living in an area prone to natural disasters like ice storms, creating an “Emergency Disaster Kit” is a vital part of preparing for severe ice storms. An emergency disaster kit is a disaster supplies kit is simply a collection of anticipated basic items that may be needed in the event of a natural disaster or other type emergency. A basic emergency supply kit could include the following recommended (or similarly so) items:
- Water, one gallon of water per person per day for at least three days, for drinking and sanitation.
- Non-perishable food items, such as energy bars, crackers, canned foods, or other types of food that require little to no preparation (i.e., heating and/or cooking).
- Food, at least a 3-day supply of non-perishable food.
- Battery-powered and/or hand crank radio and a NOAA Weather Radio with tone alert and extra batteries for both.
- Flashlight and extra batteries.
- A basic first aid kit.
- Moist towelettes, garbage bags and plastic ties for personal sanitation.
- Wrench or pliers to turn off utilities.
- A manually-operated can opener for food.
- Local maps.
- A spare cell phone with chargers, inverter, or solar charger
These items should be assembled prior to the beginning of ice storm “season,” well in advance of a possible emergency. These items should be stored in a central location in a home or other structure—such as a utility closet or cellar—where it can be easily accessed in the event of an emergency. It also a good point to remember to replace food, water and other time-sensitive items contained in the kit about twice a year. One rule of thumb is to remember to replenish and/or restock kits when the clocks are reset in spring and fall. Finally, pre-assembled disaster kits can also be purchased either on the internet, or locally should there be an anticipated need for more than one emergency kit.
During An Ice Storm (Event)
A heavy accumulation of ice will cause serious problems. In fact, the most intense ice storms can make driving impossible, disrupt electrical power out for extended periods, and bring entire regions to a standstill. As a result of the particular types of damages and disruptions that can result, ice storms can often produce many different types of hazards for those affected by them. For this reason, both preparation and knowing what to what to do—as well as what not to do—is the best way to cope with disruptions and risk of injury (or worse).
During an ice storm, stay indoors and off the roads! In the U.S., the overwhelming majority (70%) of injuries and deaths that occur as a result of ice storms are the result of traffic accidents that occur as people attempt to drive on ice-covered roadways. What’s more, the chances of being stranded if caught in an ice storm increases dramatically.
Keep a large cache of flashlights, glow sticks, and/or candles at the ready, as there is a high likelihood that lights (along with electrical power) may be disrupted. Also, keep additional batteries nearby for flashlights, as well as other battery-powered electronics such as radios and portable televisions (to keep informed about changing weather conditions).
Keep a supply of nonperishable food that requires no cooking ready. Again, there is an increased likelihood that electrical power may be disrupted—for a usually indeterminate amount of time. In the worse-case situation, it is best to be prepared for an extended period of time without being able to cook and prepare food under normal conditions. Also, make sure that a manual can opener is available.
In addition, there are other recommended courses of actions individuals can take to lessen the chances of injury and keep disruption of daily life to a minimum. These include:
- Stay inside and dress in warm, layered clothing. In addition, it helps to engage in physical activities such as some games, or even calisthenics in an effort to spur blood circulation and help stay warm.
- Close off unneeded and/or unused rooms in the home. Also, consider stuffing towels and rags underneath doors to keep out cold drafts and keep in heat.
- When using an alternative heat sources such as kerosene heaters of fireplaces, follow operating instructions, and use fire safeguards. It is also vital that areas where these alternative heat sources are used are properly ventilated.
- Cover windows at night with an unused blanket or body towel.
- Only those who have received proper instruction—of have a demonstrated history of experience—should attempt to operate a generator if you know how to operate.
The loss of electrical power is a real possibility during an ice storm. For those who can afford to make the purchase, it is a good idea to have a backup power supply in case the power goes out, such as a portable electric generator. Portable space heaters can then be used operate from the power that the generator provides.
For dwellings that use a fireplace, it is a smart policy to have an ample supply of extra firewood, cut and available ahead of the cold weather season. This will help prevent risky attempts to retrieve firewood during dangerous weather conditions as they are occurring.
A final note on the issue of staying warm during a power loss; be careful. During the colder periods of the year, the risk for carbon monoxide poisoning increases.
Carbon monoxide is an odorless, invisible gas produced when gasoline, propane, kerosene, and other fuels are not completely burned during use. Many of these fuels are the same types used in alternative heat sources such as kerosene-fueled heaters, in optional cooking equipment like propane-powered grills, and in gasoline-powered electric generators. When these items are used in well-ventilated areas (such as outdoors), they present no undue hazards. However, when they are used in indoor (and ill-advised) areas, the combustion caused by their burning fuels can result in the buildup of dangerous levels of carbon monoxide.
This accumulation of carbon monoxide can—and often does when it occurs—result in a type of poisoning that causes dangerous levels of the gas to build up in the blood of those exposed (this buildup of carbon monoxide then replaces the oxygen in the blood). Those suffering from carbon monoxide will begin to experience a variety of symptoms that include headaches, nausea, sleepiness, dizziness, weakness, and confusion. The longer someone is exposed, the worse the symptoms become. In the more extreme stages, carbon monoxide poisoning can result in coma, asphyxiation (the inability to breathe), and eventually death.
After An Ice Storm
Wait until after the ice has melted before going outside. However, if venturing outside cannot be avoided, look out for broken and/or dangling tree branches. Falling branches are an obvious injury-risk for those standing and/or walking under them. They could also disrupt electrical power if they should happen to strike or become entangled in power lines as they fall to the ground. In worst-case situations, dangling and/or falling branches that bring down power lines can indirectly cause an electrocution hazard; stepping on a live power line on a wet, cold ground can severely injure or even kill anyone coming in contact with it. For this reason, it is prudent that anyone walking among any debris on the ground left in the wake of a freezing rain event watch where they step.
In most cases, thorough planning, before-hand preparations, and vigilance afterwards can tremendously lower the likelihood of most anticipated disruptions before, during, and after an ice storm. While there is the rare instance of a storm that may cause catastrophic damage beyond planning, using both common sense and prudence can keep most people safe in the wake of ice storms and the dangers they create.
For more in-depth information about winter storms, check out our publication, "The No-Nonsense Guide To Blizzard Safety (Enhanced Edition)," by Jeffery D. Sims (available at most online retailers).
- The No-Nonsense Guide To Blizzard Safety (Enhanced Edition) by Jeffery Sims, Paperback | Barnes &
This book could save your life! The No-Nonsense Guide To Blizzard Safety (Enhanced Edition) is a very-useful resource and reference guide to everything relayed to blizzard safety.
If you've liked what you read here, please feel free to donate to help offset the costs of future publications.