Summer storms can grow to incredible heights. With so much energy available from the heat and humidity, it’s no wonder that storms can grow to over 50,000 feet this time of year.
A storm can only grow so high. After a certain point, the top of the cloud is forced to spread horizontally. The atmosphere puts a cap on just how high the clouds can grow.
Anvils are more easily seen when thunderstorms are far off in the distance. You may notice the big, thick clouds at the heart of the storm rolling upward, then thinner clouds spreading out across the highest portions of the sky. The latter is the anvil.
Many people don’t realize how dangerous the anvil can be. It certainly appears harmless. Since the anvil is made up of ice crystals, the clouds within the anvil are positively charged. Meanwhile, the earth is negatively charged.
As the anvil spreads out over the landscape, the opposing charges between the ground and the anvil may build to such levels that nature feels the need to balance the charges. A lightning strike may then be needed to balance those charges. This is rare, but it does happen.
These strikes can seem to come out of nowhere and are often called “bolts from the blue.” An anvil’s surprise strike makes it dangerous, for sure, but since the strike originated in the anvil and had to travel a great distance to the earth, the strikes carry a much higher charge than strikes that occur directly underneath the storm.
The lightning form anvils can travel tens of miles. This is why being able to hear thunder means you are close enough to be struck, especially if you can see the anvil moving overhead your location. Once again, if thunder roars go indoors!