Andy Bailey of the National Weather Service Pleasant Hill office said that situational awareness was important for weather whether you are a storm spotter or not. He said that the forecasts might call for 40% chance of showers; however, the next question was, what kind of storms?
The National Weather Service office in Pleasant Hill has 14 meteorologists and millions of equipment at their main office; however, even they cannot see everything from their office. That is because they are not allowed to shoot energy at the horizon, but must shoot it up into the sky. By the time it reaches Worth County, the waves may already be 10,000 to 12,000 high. That is too high for a Doppler Radar to pick up a tornado. That is why they rely on spotters on the ground to spot tornadoes and other damaging storms so that they can confirm what they are seeing on radar.
Sometimes, storms can strike with little or no warning. For instance, the Joplin Tornado had only 20 minutes warning before it touched down. There was no confirmation about the funnel cloud until it was almost through town. The Pleasant Hill office is staffed 24 hours a day, 7 days a week; therefore, if you're up at 3 a.m., they will take reports of hail. Their number is (800) 438-0596.
Storm spotters need to know what kind of clouds to look for. Some clouds look dangerous, but do not have the vertical growth that is necessary to produce damaging thunderstorms. The peak of severe weather is usually mid-April through mid-June. The National Weather Service produces a hazardous weather outlook for the area three times a day at www.weather.gov/kc where it has information about the possibility of severe storms. They have hazardous weather information for the next seven days.
A watch issued by the Weather Service means that conditions are favorable for the development of severe thunderstorms or tornadoes. Normally, the Weather Service has two people on site at Pleasant Hill; however, in the event of a watch or warning, they bring in 8-14 people. If you're in a tornado warning, people should take cover immediately in the lowest level of the building or in a basement or cellar; in the event of a severe thunderstorm warning, people should go indoors immediately and stay away from windows. Bailey said that it was a good idea to have a weather radio to be aware of hazardous weather; however, he admitted that it didn't always work out in his situation since his wife threw a fit every time it went off for a warning on the other side of the county. If driving and caught in a tornado, drivers should attempt to drive away from the tornado if possible. It used to be that drivers were told to get into the ditch; however, the danger of getting struck by lightning or flying debris is too great.
In the next few years, the FCC will have the telecom industry provide warning information over cell phones over the next two years.
Factors that contribute to the formation of severe storms include moisture, instability, and lift as well as updrafts and downdrafts. In the morning, the weather is stable and it is less likely to have severe storms. However, in the afternoon, as the air is warmer, the air is much less stable and severe storm clouds form later in the afternoon. Sometimes, cold and warm fronts are what provide the final push for the warm air to rise to the point where severe weather begins.
Single cell storms are usually short-lived, less than an hour in length. They are seldom severe; an exception is microbursts like the one that hit Maryville a couple of years ago. A multicell cluster has a much better chance of producing rains. It is likely to produce flooding, but rarely turns into severe weather. The most severe of these can form squall lines hundreds of miles in length.
The supercells are the ones which are most likely to form tornadoes and other severe weather. Northwest Missouri usually gets three to four of these a year. Bailey said that the thing to watch for was persistent rotation for several minutes; that is usually the precursor to a tornado and people should take cover. Most people killed in tornadoes are struck by flying debris. Bailey said that the best viewing location for a supercell was three to five miles southeast of the storm path; it is out of the tornado path and in relative safety. He said that spotters should never drive through a supercell because that was when they were likely to get hit by a tornado.
There are several types of clouds that look like tornado clouds but that are not. These include low-hanging clouds, scud clouds, and rain shafts. Bailey said that if the cloud was not rotating, then there was no tornado.
Bailey said that people should report any of the following:
--3/4" or larger sized hail;
--thunderstorm damage;
--winds of 50 miles per hour or more;
--flooding;
--tornadoes;
--heavy snow and ice;
--2" or more of rain.
When measuring the size of hail, one can use a coin. Bailey said that callers should include as much detail as possible. For instance, when reporting a flood, is the road usually flooded over during a storm? A flash flood can wash out a bridge in five minutes or less; even 18 inches of water is enough to float a car. There are more deaths through flash flooding than there are through tornadoes due to drivers trying to drive through flash flooding.
If you can hear thunder, then you can be hit by lightning. Lightning can strike up to 10 miles away from a storm; therefore, it is possible for it to strike even when the sky is clear. There is no need to report lightning to the Weather Service.
For spotters, their personal safety was the top priority. If going out at night, spotters should have at least one person go with them. It is safer now than it was five years ago since there are radar apps that can show you where you are at.
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