Each year, Iowa sees hundreds of severe and non-severe thunderstorms. Thunderstorms can be extremely dangerous storms which may bring deadly tornadoes and lightning, damaging high winds and hail and can lead to flash flooding. Understanding the dangers and being prepared for what to do during a Severe Thunderstorm may keep you and your family safe.
Warning Products from the National Weather Service (NWS)
A Thunderstorm Watch means the NWS meteorologists have determined that severe thunderstorms are likely to occur in the warned area. Watch the sky and stay tuned for warnings that may be issued.
A Thunderstorm Warning means the NWS meteorologists have determined a severe thunderstorm is occurring or likely to occur in the warned area. Warnings indicate imminent danger to life and property to those in the path of the storm.
Warnings will be issued for thunderstorms that are producing, or are capable of producing winds in excess of 58mph and hail 1 inch or greater in diameter. Oftentimes thunderstorms may be much stronger than the minimum criteria.
Lightning, straight-line winds, and hail are significant risks during a severe thunderstorm. If you are outside for school, family events, or at your favorite vacation spot watch the skies for darkening clouds and stay tuned to your portable NOAA All-Hazards weather radio or smart phone for weather updates. If you are away from your home county, know where you are to ensure you receive weather watches and warnings for that location.
Past windstorms in Story County have demonstrated the dangerous and destructive nature of severe thunderstorms and associated high winds. In order to help protect citizens that may be outside during severe storms, the Story County Emergency Management Commission adopted guidance to activate outdoor warning sirens when very high winds or large hail are observed or anticipated. Your actions if outdoor warning sirens are activated are the same for high winds, hail, and tornadoes; seek shelter in a basement or other underground shelter. Try to get under a heavy workbench or the stairs. If you do not have a basement, stay on the first floor and put as many walls between yourself and the outdoors as possible. A closet or bathroom on an inside wall, or hallway on the lowest level of the house and away from windows is recommended if you don’t have a basement. Do not call 911 to find out why the sirens have been activated, you will be hampering the ability of first responders to provide emergency services!
What you can do?
We have outlined some steps you can take to prepare before the storm. Preparing yourself and understanding what can happen during a storm may keep you and your family safe when the time comes.
Before the storm:
• Know the county in which you live or travel to on a regular basis and the major cities in those counties.
• Check the weather forecast before leaving for outdoor activities.
• Watch for signs of approaching storms.
• Have a NOAA Weather radios with a warning alarm tone and battery back-up to receive warnings.
• Postpone outdoor activities if thunderstorms are imminent.
When Storms Approach:
• Move to a sturdy building or car. Do not take shelter in small sheds, under trees or in a convertible car.
• If lightning is occurring and sturdy shelter is not available, get inside a hard top automobile and keep the windows up.
• Get out of boats, swimming pools and lakes or ponds and away from the water.
• Telephone lines and metal pipes conduct electricity. Unplug appliances not necessary for obtaining weather information and avoid using the telephone or any electrical appliances.
• Do not take a bath or shower.
If caught outdoors with no shelter:
• Find a low spot away from trees, fences and poles. Make sure the place you pick is not subject to flooding.
• Stay away from metal conductors such as wires or fences. Metal does not attract lightning, but lightning can travel long distances through it.
• If you are boating or swimming, get to land and find shelter immediately.
Information on severe weather safety can be located on the Story County Emergency Management website at http://www.storycountyiowa.gov/index.aspx?nid=99 under Disaster & Emergency Preparedness. Story County Emergency Management can also be followed through Facebook at http://www.facebook.com/storycountyema which is being used for public education and Emergency Management activities.