Meteorological Spring began March 1st and with it comes a heightened emphasis on severe weather safety and preparation. 2016 has seen an increased number of tornadoes and other severe weather events over the past few years. Is that a predictor of spring weather? One answer is…it only takes one.
It only takes one tornado or severe storm to change lives forever. It only takes one to cause millions of dollars of damage. It only takes one to impact the economy of a community. It only takes one to destroy infrastructure, schools, churches, parks, public buildings, etc.
As we remind ourselves of safety precautions, we recognize that being prepared can impact survivability reducing deaths and injuries. Damage to property can be mitigated by employing proper construction techniques.
Many states observe Severe Weather Preparedness Weeks in the spring. The National Oceanic and Atmospheric Administration’s (NOAA) Weather Ready Nation efforts consolidate information on best practices.
Beyond that information, now is a good time to review threats that are specific to a given location. Is the area prone to flooding, especially flash floods? Are outdoor sports venues equipped with lightning detectors? Are evacuation and sheltering policies in place?
Another important piece of information is local protocols for operation of outdoor warning sirens. In general, these sirens are NOT necessarily intended to be heard inside homes and businesses. Some communities sound an all clear. In others, a second activation of the sirens means the threat is continuing for an additional period of time. Some locations employ sirens for flash flooding, nuclear power plant issues, tsunamis and other threats. Be aware of local policies. Always have an alternate way of receiving severe weather information…the All-Hazards Weather Radio System, warning apps, web-based warning systems.
Personal preparedness is everyone’s responsibility. Review shelter areas at home and at work. Create appropriate “Go Kits” for each location plus vehicles. Devise a communications plan to aid in reunification of families and co-workers. Be aware of those in the neighborhood or workplace with special needs who may need your assistance. And, always, be extra vigilant when severe weather is a possibility. A community can only be as prepared as its residents.
Early this week, on July 13, a possible derecho, or at least what the National Weather Service is currently calling “a Derecho-like event,” raced across the middle of the country. It began in Minnesota and swept mostly southward through Wisconsin, Illinois, parts of Indiana and into Kentucky.
The Weather Service describes a derecho as “a widespread, long-lived storm. Derechos are associated with bands of rapidly moving showers or thunderstorms variously known as bow echoes, squall lines or quasi-linear convective systems.”
The “bow echo” refers to the characteristic appearance of a linear storm on weather radar when that storm bows out due to high wind. Storms represented by bow echoes are not always derechos unless they last for a long time which is rarely the case. In fact, large derechos are relatively unusual. Generally there are only one or two a year in most of the country.
Derechos can be extremely damaging. By definition a derecho must travel 240 miles and include wind gusts of at least 58mph along much of its length and several gusts of over 75mph. Many are much stronger. A derecho that crossed Illinois from northwest to southeast in the late 1990’s included winds measured at over 100mph at the Clinton nuclear power plant and caused extensive damage to a marina at the associated cooling lake.
Effects can be long lasting. On July 4th and 5th in 1999 a derecho crossed the Boundary Waters Canoe area in northern Minnesota/southern Ontario. It devastated a forest there. Wildfires in more recent years have been fueled by the debris from that storm.
Because of their length and the intensity of the straight line winds, derechos can be an extremely costly event. Casualties are rare, but do occur, usually caused by falling trees or other debris and occasionally by watercraft caught by the rapidly moving storms.
We’ll keep things short this week as your author needs to hit the road for visits to our Chicago-area Extension offices.
In some parts of the country, this is Lightning Safety Awareness Week. The following passage is from the Peoria Journal Star on Monday, June 22, 2015: … the motorcyclists were traveling side-by-side when lightning hit a taxi van and then the motorcyclists. The driver of the van was injured, but survived, after going into a ditch, but the motorcyclists, who were burnt and suffered heart attacks, died at the scene. This freak accident occurred in Decatur, Illinois and points to just how unpredictable and dangerous lightning can be.
Severe storms are forecast in a large part of the Great Lakes region and points east early in the week, so I’d like to share a National Weather Service link that tells you just about everything you need to know about lightning safety.