This is Severe Weather Awareness Week in Alabama. All week long, the National Weather Service will be highlighting a different severe weather threat that affects our state. Today is devoted to severe thunderstorms. Tuesday will highlight lightning. Wednesday will feature the tornado threat and feature the annual statewide tornado drill. Thursday will spotlight the number one weather killer in the United States...flooding and flash flooding. Finally, Friday will wrap up the week with a focus on NOAA All-Hazards Weatheradio and the Emergency Alert System day.
There are three kinds of thunderstorms. Single cell, multi cell and supercell. Single cell, or pulse thunderstorms frequently occur in the summer months. They develop when unstable air develops into a thunderstorm updraft. They are not organized and generally rain themselves out as they choke on their own downdrafts. They generally do not become severe, which is defined as a storm with winds 58 mph or greater or hail 3/4 of inch or larger (penny size.) But they still can be killers producing deadly lightning and very heavy rainfall that can cause flooding.
Multi cell thunderstorms form when atmospheric wind profiles are conducive to tilting the thunderstorm updraft away from the downdraft and precipitation core. Thunderstorm clusters and squall lines are examples of multi cell thunderstorms. These storms often become severe, frequently producing damaging winds and occasional tornadoes in addition to the usual threats of lightning, hail and very heavy rains.
Supercell thunderstorms are the kings of the sky. They form when instability levels are high and spin in the atmosphere is plentiful. This spin, called helicity can set a thunderstorm to rotating like a top. These storms are most likely to produce long track ,damaging tornadoes, as well as winds over 100 mph, very large hail and the usual complement of deadly lightning and flooding rains. They usually like to be isolated by themselves to reach their destructive potential, but they can be embedded in squall lines or in clusters. Supercells are most common in the primary severe weather seasons of Spring and Fall.
Severe thunderstorm warnings are issued when radar indicates a storm may be severe or actual ground truth reports indicate the criteria has been reached. Severe thunderstorm warnings should always be taken seriously, although many people believe the criteria for severe thunderstorms should be raised. In any case, the best idea is to be in a substantial building or home when a thunderstorm threatens. Stay away from windows and avoid using the telephone and electrical appliances because of lightning. Mobile homes should be vacated for safer structure as strong winds can overturn them easily.
There are three kinds of thunderstorms. Single cell, multi cell and supercell. Single cell, or pulse thunderstorms frequently occur in the summer months. They develop when unstable air develops into a thunderstorm updraft. They are not organized and generally rain themselves out as they choke on their own downdrafts. They generally do not become severe, which is defined as a storm with winds 58 mph or greater or hail 3/4 of inch or larger (penny size.) But they still can be killers producing deadly lightning and very heavy rainfall that can cause flooding.
Multi cell thunderstorms form when atmospheric wind profiles are conducive to tilting the thunderstorm updraft away from the downdraft and precipitation core. Thunderstorm clusters and squall lines are examples of multi cell thunderstorms. These storms often become severe, frequently producing damaging winds and occasional tornadoes in addition to the usual threats of lightning, hail and very heavy rains.
Supercell thunderstorms are the kings of the sky. They form when instability levels are high and spin in the atmosphere is plentiful. This spin, called helicity can set a thunderstorm to rotating like a top. These storms are most likely to produce long track ,damaging tornadoes, as well as winds over 100 mph, very large hail and the usual complement of deadly lightning and flooding rains. They usually like to be isolated by themselves to reach their destructive potential, but they can be embedded in squall lines or in clusters. Supercells are most common in the primary severe weather seasons of Spring and Fall.
Severe thunderstorm warnings are issued when radar indicates a storm may be severe or actual ground truth reports indicate the criteria has been reached. Severe thunderstorm warnings should always be taken seriously, although many people believe the criteria for severe thunderstorms should be raised. In any case, the best idea is to be in a substantial building or home when a thunderstorm threatens. Stay away from windows and avoid using the telephone and electrical appliances because of lightning. Mobile homes should be vacated for safer structure as strong winds can overturn them easily.