What data and patterns do meteorologists use to measure the intensity and predict the impact of catastrophic events such as flooding hurricanes and tornadoes?

Answer 1

Different factors are used for each of them, though they do share some in common.

Floods:

Their intensity may be measured either as the rate of water discharge in a stream or height of the surface above flood stage. Discharge rate is used to calculate the expected recurrence rate of a flood. Potential floods are predicted by analyzing how much precipitable moisture (moisture that can fall as rain or snow) is in the atmosphere, and whether the right conditions (e.g. a front) to trigger rain or snowmelt. Analyzing topography is used to predict what areas are at the greatest risk of flooding.

Hurricanes:

Hurricanes are rated into categories based on their sustained wind speeds, which can be used to estimated damage potential. Scientists keep an eye on a number of factors that can either help or hinder a hurricane. They form and strengthen best over very warm ocean water in moist air with little to no wind shear, so the main factors in intensity forecasts for hurricanes are seas surface temperature, humidity, and wind shear. Tracking large scale wind currents and high and low pressure systems allow scientists tor predict the likely path of a hurricane. The behavior of past hurricanes is factored into these predictions. Combined forecast of intensity and path show where a hurricane is likely to hit and how strong it may become.

Tornadoes:

Tornadoes are rated based on wind speed estimates derived from the damage they cause. Like hurricanes and floods, tornadoes and the storms that produce them depend a lot on moisture and temperature. They form best when a cool, dry in mass pushes into a warm, moist one. Wind shear is also important; unlike hurricanes, tornadoes actually need strong wind shear in order to form. Another factor is a layer of stable air called and inversion cap, which can cut both ways; it holds storms back and can prevent them from developing, but when storms do manage to punch through it they be stronger and more likely to produce tornadoes. Short term prediction is also important. The main factor for tornadoes is rotation within a thunderstorm; strong rotation means a very high potential that a tornado will form or has already formed.