In the backyard meteorology series, this is the second writing that involves instability. Storm and cloud observations are a popular reason to do backyard weather observing. Instability release involves strong convective vertical motions that develop into thunderstorms. Towering cumulus and storms can make for some of the most amazing photography. While instability is difficult to see physical, instability release is easy to see as evidenced by the towering thunderstorm clouds. The storm is made visible by cloud droplets, rain, hail, ice particles, lightning and sunlight. These can combine together to produce amazing colors and threatening skies. When instability release occurs it is known that the cap is broken. Once one storm forms it can lead the way for more storms to develop since the first storm can provide outflow lifting mechanisms that can aid in the development of more storms. Several storms can sometimes be witnessed, some closer and some in the distance. The top of the storm will show an anvil of frozen ice particles that has a wispy appearance at high elevations above and downwind from the storm. These anvils seen in the distance are evidence that a storm has developed. When observing in the backyard, thoughts will occur if the storm will hit your location or not and if you will get the worst of the storm. Once the storm develops, observe the cloud movements and storm motion to get an idea if it will move to your location. The first experience as a storm approaches will often be a gust front of cooling wind. As the storm gets closer the rain curtain will be seen getting closer and closer to being over head. As the rain curtain moves over then heavy rain can quickly begin. If the storm is severe then severe wind, hail or a tornado will be associated with the storm. Two other dangers from storms are flooding rain and lightning. If a storm is slow moving and overhead it can dump a large volume of rain on one location. Any thunderstorm is capable of producing dangerous lightning thus it is recommended to stay inside during the storm. Once the storm is close or overhead then thunder will be crashing close by. Thunder travels about a mile for every 5 seconds from when the lightning is seen. Thus for example, when lightning is seen and thunder is heard 10 seconds later then the strike was about 2 miles away. |