April showers bring May…spring weather hazards
- Spring weather hazards are caused by warm southern air pushing up into cold northern air.
- This atmospheric phenomenon can cause tornadoes, thunderstorms, floods, hail, gusty wind, wildly fluctuating temperatures – and even more winter storms.
- Learn how to protect yourself and your family from each of these often-unpredictable weather events.
Weather this time of year is often unpredictable, bringing multiple spring weather hazards. When severe weather hits unexpectedly, the risk of injury and weather-related death increases. So it’s best to prepare now for storms, floods and tornadoes, as if you know in advance they’re headed your way – because in the spring, they very likely will.
Nationwide, March, April and May can see 20-90° days, a blizzard that dumps a foot of snow, a tornado that destroys everything in its path for miles, or thunderstorms with enough rain to cause severe flooding.
Sometimes extreme weather changes can occur even within the same day. Mark Twain once said, “In the spring I have counted one hundred and thirty-six kinds of weather inside of four and twenty hours.”
Thunderstorms typically cause most of the severe spring weather hazards, bringing lightning, tornadoes, and flooding. Whenever warm, moist air collides with cool, dry air, thunderstorms can occur. This usually happens in spring and summer.
Related: Flood preparedness and recovery for homeowners
Because spring weather is so unpredictable, you may be unprepared when severe weather hits—particularly if you live in a region that doesn’t often experience thunderstorms, tornadoes or flooding. When severe weather hits unexpectedly, the risk of injury and death increases, so planning ahead makes sense. Prepare for storms, floods, and tornadoes as if you know in advance they are coming, because in the spring, they very likely will, says the CDC in their weather article.
Tornado threats peak in spring
Violently rotating columns of air with wind speeds over 200 mph, tornadoes extend from a thunderstorm to the ground. At anytime and anywhere, they can destroy buildings, flip cars and create deadly flying debris.
March is the least-active spring month for twisters to form, with an average of about 92, says Fox Weather. That number skyrockets in April, with an average of 212 tornadoes, and increases even further in May, with an average of 294 twisters. May is historically the most active tornado month in the U.S.
Where do tornadoes typically form?
Typically, tornadoes form anywhere from North Dakota down to Texas, and all states east.
Tornado outbreaks are most common when a strong southward dip in the jet stream punches into the Plains or Midwest, and warm, humid air from the Gulf of Mexico surges northward out ahead of it at the surface, says Fox.
That strong jet stream fuels severe weather, adding the twisting and energy needed to develop and intensify thunderstorms, potentially developing them into supercell storms that might produce tornadoes.
Related: 8 tornado safety tips for homeowners and business owners
In spring, the jet stream migrates northward to hover over the Plains and Midwest (aka Tornado Alley) and then moves farther north toward the Canadian border for the summer.
Tornado preparation steps
If you are under a tornado or severe weather warning, Ready.gov recommends that you:
- Go to NOAA Weather Radio and your local news or official social media accounts for updated emergency information. Follow the instructions of state, local and tribal officials.
- Go to a safe shelter immediately, such as a safe room, basement, storm cellar or a small interior room on the lowest level of a sturdy building.
- Stay away from windows, doors and outside walls.
- Do not try to outrun a tornado in a vehicle. If you are in a car or outdoors and cannot get to a building, cover your head and neck with your arms and cover your body with a coat or blanket, if possible.
- Do not go under an overpass or bridge. You’re safer in a low, flat location.
- Watch out for flying debris that can cause injury or death.
- Use your arms to protect your head and neck.
- If you can’t stay at home, make plans to go to a public shelter.
- Once the all-clear has sounded, stay clear of fallen power lines or broken utility lines.
Tornado survivors say having a plan on where to take cover saved their life. Tornadoes can occur with almost no warning. Where will you take cover? Learn more about staying safe during a tornado at https://www.ready.gov/tornadoes.
Thunderstorms bring lighting and hail
U.S. hailstorms cause an average of $15 billion in damage to homes, cars and crops each year. The largest hailstones captured in the U.S. were back in 2010 and measured 8” in diameter, 18.5” in circumference, and weighed just shy of two pounds. Hail can cause untold damage, so keep vehicles covered when possible and provide shelter for all outside animals.
Every year there are about 25 million cloud-to-ground lightning flashes in the U.S. Lightning can strike up to 10 miles from a thunderstorm – about the distance that you can hear thunder from a storm. That means if you can hear thunder, you’re likely within striking distance.
Each one of those flashes is a potential killer. If the sky looks threatening, don’t wait for that first flash of lightning or thunder rumble. That first flash can be just as deadly as any other flash in the storm.
Learn lightning safety tips from our earlier blogpost on How to prevent lightning injuries and damage at your home and business .
Major winter storms may occur
Although the calendar says it’s spring, it’s not necessarily the end of winter weather in many areas just yet.
Major winter storms, including blizzards, are possible in many areas of the U.S. during the spring. The regions that face the most significant winter/spring weather hazards include the Rockies and the adjacent Front Range eastward into the Plains and Upper Midwest.
In fact, March through mid-May are often the snowiest months of the year in parts of the Rockies, High Plains and northeast into upper New England. Sometimes these storms even produce blizzard conditions. Typically May dumps the heaviest snow of the year in the Front Range of Colorado where this author lives.
Spring weather hazards include flooding
Flooding, a temporary overflow of water onto land that’s normally dry, is the most common natural disaster in the U.S. Failing to evacuate flooded areas or entering flood waters can lead to injury or death.
The worst flooding happens when bouts of heavy rain move across an area where the ground is already saturated from winter snowmelt or rain. Since the ground cannot absorb any of the rain, serious flooding can occur and potentially inundate city streets and even homes.
Related: Business tips during and after a flood
River flooding can also become a serious concern in the spring, especially from the Plains to the Midwest and portions of New England. The threat of flash floods also increases as thunderstorms become more frequent due to spring’s warmer, more humid air. Thunderstorms can produce rainfall rates of an inch or more than an inch per hour. Major flash flooding can occur with no warning if that heavy rain persists for several hours in a particular area. It can cause outages, disrupt transportation, damage buildings and create landslides.
If you are under a flood warning, take these precautions:
- Learn what to do before, during & after a flood by visiting https://www.ready.gov/floods.
- Evacuate immediately, if told to evacuate. Never drive around barricades. Local responders use them to safely direct traffic out of flooded areas.
- Contact your healthcare provider If you are sick and need medical attention. Wait for further care instructions and shelter in place, if possible. If you are experiencing a medical emergency, call 9-1-1.
- Listen to EAS, NOAA Weather Radio or local alerting systems for current emergency information and instructions regarding flooding.
- Do not walk, swim or drive through flood waters. Turn around. Don’t drown!
- Stay off bridges over fast-moving water. Fast-moving water can wash bridges away without warning.
- Stay inside your car if it is trapped in rapidly moving water. Get on the roof if water is rising inside the car.
- Get to the highest level if trapped in a building. Only get on the roof if necessary and once there signal for help. Do not climb into a closed attic to avoid getting trapped by rising floodwater.
Spring brings heavy winds
March and April are the windiest months for many cities nationwide. That’s because strong wind gusts are often ushered in by storm systems that track across the U.S. Gusty winds often accompany potent spring storms before, during and after their passage through the Lower 48. Sometimes those winds can contribute to blowing dust in the Southwest and Plains states.
Wild temperature swings cause spring weather hazards
Spring is also known for its up and down changing temperatures. Warm air typically surges into a region out ahead of an area of low pressure or a cold front and provides a taste of spring warmth, but temperatures can drop rapidly behind the storm system as colder air rushes back in from the north and northwest in its wake.
It’s particularly true in March and April when strong low-pressure systems moving through the central and eastern states draw warm air ahead of them into the northern tier of the country. Residents can enjoy couple of warm, refreshing days. But an inevitable cold plunge typically arrives after the storm departs removing those nice warm spring temperatures.
More prolonged warm weather becomes common later in the spring and the atmosphere becomes less prone to wild temperature swings as cold air retreats back to Canada when summer approaches.
Prepare for spring weather hazards
Advance planning for thunderstorms, lightning, tornadoes and floods requires specific safety precautions. You can follow many of the same steps for all extreme weather events, says the CDC. They recommend you keep an emergency kit on hand with these items:
- A battery-operated flashlight, a battery-operated NOAA Weather Radio, and extra batteries for both
- An emergency evacuation or shelter plan, including a map of your home and, for every type of severe weather emergency, routes to safety from each room
- A list of important personal information, including:
- telephone numbers of neighbors, family, and friends
- insurance and property information
- telephone numbers of utility companies
- medical information
- The American Red Cross a first aid kit recommends including:
- non-latex gloves
- an assortment of adhesive bandages
- antibiotic ointment
- sterile gauze pads in assorted sizes
- absorbent compress dressings
- tweezers
- scissors
- adhesive cloth tape
- aspirin packets (81 mg each)
- a first aid instruction booklet (NOTE: Customize your first aid kit to meet your individual and family needs.)
- A 3- to 5-day supply of bottled water and nonperishable food
- Personal hygiene items
- Blankets or sleeping bags
- An emergency kit in your car
The CDC recommends that you prepare your family members for the possibility of severe weather. Tell them where to seek appropriate shelter as soon as they are aware of an approaching storm. Practice your emergency plan for every type of severe weather. Show family members where the emergency supplies are stored, and make sure they know how to turn off the water, gas, and electricity in your home.
Advance planning for thunderstorms, lightning, tornadoes, and floods requires specific safety precautions. Often by the time we are aware of an approaching storm, we have little if any time to prepare for it. CDC suggests you take the surprise factor out of severe weather and prepare yourself, your family and your home. Then, if thunderstorms, tornadoes or floods do occur, you’ll be ready for them.