Thunderstorms

Question 1

How does a thunderstorm form?

Answer 1

There needs to be unstable atmospheric conditions, a lifting force, and high moisture levels.

Generally the lifting force leading to a thunderstorm is caused by rising air due to terrain, rising air due to unequal warming of the earth’s surface and rising air due to warm or cold fronts.

Question 2

What are the three types of thunderstorms?

Answer 2

Air mass, steady-state, and non-frontal.

Question 3

Air Mass Thunderstorm

Answer 3

An air mass thunderstorm is not associated with a front or colliding of two air masses but rather a single, unstable air mass.
They usually develop locally during the afternoon or late in the day in response to insolation through convective heating from the surface.
Typically they only last an hour or two and dissipate after sunset.

Question 4

Steady-state Thunderstorm

Answer 4

A steady-state thunderstorm is usually associated with colliding of air masses (fronts), winds, and pressure systems.
In a steady-state storm, precipitation falls outside the updraft allowing the updraft to continue unabated. Thus, the mature stage updrafts become stronger and last much longer than in air mass thunderstorms.
A steady-state thunderstorm may persist for hours.
Steady-state thunderstorms often develop into squall lines.

Question 5

Non-frontal Thunderstorm (Squall Line)

Answer 5

Sometimes, thunderstorm cells can become organized within a long line that precedes a cold front. This is known as a squall line.
A squall line is a non-frontal, narrow band of active thunderstorms that often develop ahead of a cold front.
They are accompanied by “squalls” of high wind, heavy rain and possible hail. They can extend over 100 miles and move quickly, up to 60 mph.

Question 6

What are the 3 stages of a thunderstorm?

Answer 6

1. Cumulus or Developing Stage
2. Mature Stage
3. Dissipating Stage

Question 7

Cumulus or Developing Stage

Answer 7

The continuous updraft or lifting of air into the upper atmosphere which cools the air and condenses the water vapor within the air into water droplets or ice crystals forming towering, cumulus clouds.
High winds and occasional lightning.

Question 8

Mature Stage

Answer 8

Precipitation falling marks the start of the mature stage.
Thunderstorm is at its greatest intensity.
Very turbulent conditions
High winds
Frequent lightning

Question 9

Dissipating Stage

Answer 9

Characterized by downdrafts as energy is released from the storm causing it to weaken.
Lightning is common in this stage as well.