Tornadoes typically accompany severe thunderstorms that develop in warm, moist, unstable air, often along or ahead of cold fronts. These thunderstorms can also produce large hail and damaging winds
. The key atmospheric conditions leading to tornado formation include instability (warm, moist air near the ground with cooler, dry air aloft) and wind shear (a change in wind speed and/or direction with height), which promotes strong updrafts and rotation within the storm
. The most common type of storm producing tornadoes is the supercell thunderstorm, a long-lived and severe thunderstorm with a rotating updraft called a mesocyclone. Tornadoes form from this rotation extending downward to the ground
. In summary, the weather accompanying tornadoes is characterized by:
- Severe thunderstorms with heavy rain
- Large hail
- Strong, damaging winds
- Warm, moist, unstable air masses
- Presence of wind shear promoting storm rotation
These conditions often occur during spring and summer but can happen any time of the year when the atmospheric ingredients align