Meteorology Monday (6-9-25): The Cap
We know that air usually gets colder with height, and we know that heat rises. When the sun heats up the surface during the day, updrafts of warm air rise and the cooler, surrounding air sinks. As long as the surrounding air remains cooler with height, updrafts continue to rise. This process feeds into the water cycle and is how clouds form in the sky.
Sometimes, there is a layer of air in the atmosphere that is warm, and we call this layer an inversion, or a capping inversion. This is because when the updraft reaches this layer, it is no longer warmer than the surrounding air, and the warmer layer limits, or caps, clouds from growing much taller into the towering cumulus clouds that form thunderstorms.
If the updraft is warm enough, or more moisture is filtered in, or even if the cap is thin or weak in some areas, the updrafts can 'break the cap' and rapidly develop into a strong or severe thunderstorm.
Once the thunderstorm happens, your 18 Storm Team and local NWS offices will be all over keeping you safe and informed, so you're next steps will be to seek shelter and stay weather aware.
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