Thunderstorms are atmospheric events characterized by lightning and thunder, often accompanied by precipitation and strong winds. These storms vary significantly in intensity, from mild to severe. Understanding the qualities of a “moderate” thunderstorm is important for recognizing potential impacts and taking appropriate safety measures, as they can still cause disruption.
Defining Moderate Thunderstorms
A moderate thunderstorm typically exhibits conditions that fall below the official criteria for a severe thunderstorm but are still capable of causing minor damage and posing hazards. For a storm to be classified as severe, it generally must produce wind gusts of 58 miles per hour (mph) or greater, hail one inch in diameter or larger, or a tornado. Moderate thunderstorms, therefore, usually feature wind gusts that are strong but remain below 58 mph, often in the range of 35 to 57 mph. These winds can still be strong enough to dislodge loose outdoor items or cause minor tree limb damage.
Hail associated with moderate thunderstorms is typically smaller than the one-inch threshold for severe storms, often described as pea to marble-sized. While not as destructive as larger hail, even small hailstones can accumulate and create slick surfaces. Rainfall intensity during a moderate thunderstorm can be heavy, leading to significant downpours that may reduce visibility and contribute to localized street flooding if prolonged. However, such rainfall is not usually expected to cause widespread or severe flash flooding.
Lightning is an inherent component of all thunderstorms, and moderate storms are no exception. They often produce frequent lightning, indicating a significant electrical presence. While frequency varies, lightning strikes are a consistent danger. Even though these storms are termed “moderate,” they are not “mild” and still carry genuine risks to safety and property.
Staying Safe During Moderate Thunderstorms
Protecting oneself and property during a moderate thunderstorm involves taking practical steps to minimize risks, even though the storm may not be classified as severe. The primary safety guideline is to seek sturdy shelter indoors as soon as thunder is heard, following the adage, “When Thunder Roars, Go Indoors!”. Sheds, tents, and open structures like gazebos do not provide adequate protection from lightning or strong winds. If a sturdy building is unavailable, an enclosed vehicle with windows rolled up can offer a safer alternative than remaining outdoors.
Once inside a safe structure, it is advisable to stay away from windows and doors, as these areas offer less protection from flying debris that strong winds might carry. It is also important to avoid contact with water during a thunderstorm, as lightning can travel through plumbing systems. This means refraining from activities such as showering, bathing, or washing dishes until the storm has passed.
To safeguard electronics from potential power surges caused by lightning, unplug sensitive appliances and devices before the storm arrives. Surge protectors offer some defense, but direct unplugging provides the most reliable protection. Landline phones should not be used during a thunderstorm due to the risk of lightning traveling through the phone lines, though cordless or cellular phones are generally considered safer if not plugged into a charger.
For individuals caught outdoors when a moderate thunderstorm approaches, finding immediate shelter is paramount. Avoid seeking refuge under tall objects like isolated trees, in open fields, or near bodies of water, as these locations increase the risk of a lightning strike. If no substantial shelter is accessible, crouching low to the ground in a ditch or depression, minimizing contact with the earth, can offer a small degree of protection. Monitoring local weather alerts and forecasts allows individuals to anticipate and respond to changing conditions.