Tornado in the context of "Landspout"

A natural phenomenon is an observable event which is not man-made. Examples include: sunrise, weather, fog, thunder, tornadoes; biological processes, decomposition, germination; physical processes, wave propagation, erosion; tidal flow, and natural disasters such as electromagnetic pulses, volcanic eruptions, hurricanes and earthquakes.

A natural disaster is the very harmful impact on a society or community brought by natural phenomenon or hazard. Some examples of natural hazards include avalanches, droughts, earthquakes, floods, heat waves, landslides - including submarine landslides, tropical cyclones, volcanic activity and wildfires. Additional natural hazards include blizzards, dust storms, firestorms, hails, ice storms, sinkholes, thunderstorms, tornadoes and tsunamis.

A natural disaster can cause loss of life or damage property. It typically causes economic damage. How bad the damage is depends on how well people are prepared for disasters and how strong the buildings, roads, and other structures are.

Extreme weather includes unexpected, unusual, severe, or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. Extreme events are based on a location's recorded weather history. The main types of extreme weather include heat waves, cold waves, droughts, and heavy precipitation or storm events, such as tropical cyclones. Extreme weather can have various effects, from natural hazards such as floods and landslides to social costs on human health and the economy. Severe weather is a particular type of extreme weather which poses risks to life and property.

Weather patterns in a given region vary with time, and so extreme weather can be attributed, at least in part, to the natural climate variability that exists on Earth. For example, the El Niño-Southern Oscillation (ENSO) or the North Atlantic oscillation (NAO) are climate phenomena that impact weather patterns worldwide. Generally speaking, one event in extreme weather cannot be attributed to any one single cause. However, certain system wide changes to global weather systems can lead to increased frequency or intensity of extreme weather events.

In fluid dynamics, a vortex (pl.: vortices or vortexes) is a region in a fluid in which the flow revolves around an axis line, which may be straight or curved. Vortices form in stirred fluids and may be observed in smoke rings, whirlpools in the wake of a boat, and in the winds surrounding a tropical cyclone, tornado, or dust devil.

Vortices are a major component of turbulent flow. The distribution of velocity, vorticity (the curl of the flow velocity), as well as the concept of circulation are used to characterize vortices. In most vortices, the fluid flow velocity is greatest next to its axis and decreases in inverse proportion to the distance from the axis.

A weather god or goddess, also frequently known as a storm god or goddess, is a deity in mythology associated with weather phenomena such as thunder, snow, lightning, rain, wind, storms, tornadoes, and hurricanes. Should they only be in charge of one feature of a storm, they will be called after that attribute, such as a rain god or a lightning/thunder god. This singular attribute might then be emphasized more than the generic, all-encompassing term "storm god", though with thunder/lightning gods, the two terms seem interchangeable. They feature commonly in polytheistic religions, especially in Proto-Indo-European ones.

Storm gods are most often conceived of as wielding thunder and/or lightning (some lightning gods' names actually mean "thunder", but since one cannot have thunder without lightning, they presumably wielded both). The ancients didn't seem to differentiate between the two, which is presumably why both the words "lightning bolt" and "thunderbolt" exist despite being synonyms. Of the examples currently listed storm themed deities are more frequently depicted as male, but both male and female storm or other rain, wind, or weather deities are described.

Tornado Alley, also known as Tornado Valley, is a loosely defined location of the central United States where tornadoes are most frequent. The term was first used in 1952 as the title of a research project to study severe weather in areas of Texas, Louisiana, Oklahoma, Kansas, South Dakota, Iowa and Nebraska. Tornado climatologists distinguish peaks in activity in certain areas and storm chasers have long recognized the Great Plains tornado belt.

As a colloquial term there are no definitively set boundaries of Tornado Alley, but the area common to most definitions extends from Texas, through Oklahoma, Kansas, Nebraska, South Dakota, Iowa, Minnesota, Wisconsin, Illinois, Indiana, Missouri, Arkansas, North Dakota, Montana, Ohio, and eastern portions of Colorado, New Mexico and Wyoming. Research suggests that the main alley may be shifting eastward away from the Great Plains, and that tornadoes are also becoming more frequent in the northern and eastern parts of Tornado Alley where it reaches the Canadian Prairies, Ohio, Michigan, and Southern Ontario.