Tropical cyclones consist of three main parts: the eye, the eyewall, and rainbands

Tropical cyclone formation require warm water and limited vertical wind shear

Ocean temperatures above 27 degrees Celsius fuel rising, moist air, which releases energy through heat as water vapor condenses into clouds. Significant changes in wind speed with height can spread out these upflows, preventing the eventual formation of a central column known as the eye.

All hurricanes have a central eye where no extreme weather phenomena take place

When standing in the eye of a hurricane, you're likely to experience sunny, cloudless skies surrounded by a wall of intense winds and thunderstorms. The physics behind this formation is the same as what causes water to spiral around a hollow cone as it goes down a drain.

Tropical cyclones are called hurricanes, typhoons, and cyclones around the world

Tropical cyclones are named differently based on their region of origin due to historical traditions and cultural importance. These storms are called hurricanes in the Atlantic and northeast Pacific oceans, cyclones in the southwest Pacific and Indian oceans, and typhoons in the northwest Pacific Ocean.

How do hurricanes form?

Tropical cyclones, also called hurricanes and typhoons, cause catastrophic damage when they strike land. This four-minute video explores the life cycle of cyclones—how atmospheric conditions, ocean temperatures, and the Earth’s rotation combine to create them, and how they are driven by winds and eventually weaken after moving over land.

Hurricanes can grow by replacing their eyewall

A second outer eyewall can form around the primary eyewall surrounding a hurricane's eye. During an eyewall replacement cycle, the outer wall can weaken, collapse, and replace the inner wall, temporarily weakening the storm before it strengthens and grows.

Bomb cyclones can produce heavy rain, blizzard conditions, and intense winds

Known as "bombogenesis" in meteorology, these systems get their colloquial name from their rapid intensification over a 24-hour period—a phenomenon seen in some tropical cyclones. They occur most commonly along the coasts of the Northeast and Northwest US when there is a severe temperature difference between colliding air masses.

The way hurricanes are categorized may mislead the public to their dangers

The Saffir-Simpson scale categorizes hurricanes based on wind speed, but tropical cyclones' main dangers are storm surges and heavy rainfall. To better communicate risks to the public, a new system that incorporates hurricane size, water content, and other complexities should be developed.

Various types of tornadoes are distinguished by their shape, size, and location

Waterspouts form over water as long, thin columns of mist and air, while elephant trunks are tornadoes that elongate vertically as they become tilted during their formation, resembling the mammal's appendage. Wedge tornadoes are among the most powerful, often spanning a mile or more in width.

Trade winds blow from east to west due to the Coriolis Effect

Warm air rises near the equator while cooler air sinks near the poles, creating circulation patterns that curve due to Earth's rotation. At the equator, doldrums—calm regions of no wind—build warm, moist air, creating storms.

Atmospheric processes amplify the strength of storms by coalescing clouds

Research has shown that turbulent mixing of air at the edges of clouds and other small-scale thermal activity beneath them help clouds group together, intensifying short bursts of rainfall, especially in tropical regions. Simulations reveal this produces more powerful storms than predicted by older models, though they may occur less frequently.

Learn all about different types of extreme weather

Find out in more detail about different types of extreme weather, from flooding to thunderstorms, from tropical cyclones to sandstorms, and more (w/ helpful videos).

The cone of uncertainty predicts where a hurricane's center can potentially travel

A common misconception is that regions beyond the cone are safe, but the spread does not depict the full reach of a cyclone's wind, rain, or storm surges. The cone is not built from real-time storm data but is an average forecast error from the past five years.

In Doppler radar imaging, a 'hook echo' helps identify a tornado-producing thunderstorm

Typically found in the right-rear part of a storm relative to its motion, the "hook" is the hallmark of a mesocyclone—a large, rotating updraft of air—within supercells, the most powerful thunderstorms. While tornadoes are known to develop within mesocyclones, they can also be detected by storm spotters trained to recognize tornado conditions in their communities.

The National Weather Service communicates tornado risks on a three-tier system

During a tornado watch, atmospheric conditions favor the development of a tornado, and residents in an area should be prepared to seek refuge. A tornado warning is issued if a tornado has been detected, while a tornado emergency indicates a violent tornado has touched down in the area, with severe threats to human life and property expected.

Dust from the Sahel and Saharan regions makes northwest Africa a hurricane nursery

NASA’s Convective Processes Experiment—Cabo Verde studied the early stages of hurricane formation, identifying how dust interacts with clouds over the ocean to produce the rainy disturbances that become tropical cyclones.

An overview of Earth's atmospheric cells and how they distribute Earth's uneven heating

The Hadley, Ferrel, and Polar cells are circulation patterns that act like gears, moving warmer air from the equator to the poles. The rising and falling of air currents within these patterns creates semi-persistent regions of low and high pressure, which contribute to the formation of regional climates, such as tropical zones.

Hurricanes, which rely on air consistently spinning in the same direction, cannot cross the equator because air curves in opposite directions north and south of it.

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

Rivers in the sky

A short introduction to atmospheric rivers, including a handy illustration on the science behind them, the phenomena that help transport water vapor from the tropics across the globe.

View the ten basic cloud types, categorized by height and composition

Among the features of these types, cirrus clouds can display various colors at sunrise and sunset, while altocumulus clouds can produce a corona phenomenon around the sun or moon. Nimbostratus clouds are thick enough to block out the sun entirely.

From evaporation to precipitation: An overview of the water cycle

The water cycle is a natural process that continuously circulates water throughout Earth's systems. View this diagram from NASA to understand how the water cycle incorporates evaporation, condensation, precipitation, and more. First, the sun's heat...

All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.

View a gallery of the best images of Jupiter from the Juno mission

Using the JunoCam, scientists have observed several of Jupiter's features, including cyclones, the Great Red Spot, and cloud bands and zones. The mission's effectiveness has resulted in its extension from July 2021 to September 2025.

Rain-catching tubes provide new hydropower source for tropical regions

An experiment in Singapore showed that charge separation could be established by rainwater flowing through narrow tubes. The separation, which creates a voltage, could be scaled up in regions of high rainfall to provide a clean energy source.

Dirty lightning is a thunderstorm created from friction between rising and falling flows of ash and smoke during volcanic eruptions.

View the three types of coral reefs, categorized by where they form

Fringing reefs—the most common type—are built from coral depositing calcium carbonate onto the seafloor closest to the shoreline. Barrier reefs grow further from and parallel to the shore, while atolls are the result of mid-ocean volcanoes or seamounts eroding away and leaving a lagoon surrounded by reefs.

Chaos theory—informally known as the butterfly effect—is the reason why weather forecasts are presented with probabilities rather than certainties.

The four types of seismic waves are categorized as body or surface waves

Primary (P) and secondary (S) waves are compression and shear waves, respectively, and travel through Earth’s interior, though secondary waves only move through solids. These waves’ energy is converted into rolling Rayleigh or horizontal Love waves at the surface.

Cyclotrons move particles in spiral paths of increasing radius

After particles are injected into the center of the device, an alternating electric field and a constant magnetic field energize the particles as they spiral outward toward a target. Cyclotrons are common in hospitals that perform molecular imaging, which relies on radioactive components that decay within hours.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

View the ten deadliest tornadoes in US history.

Explore the known asteroids, comets, and spacecraft involved in asteroid studies within our solar system with 'Eyes on Asteroids,' a 3D visualization from NASA.

Corals are themselves not coral reefs—the term refers to the tiny marine invertebrates that build the rigid reef.

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

Three Ebola species are responsible for most large outbreaks of the disease, yet the only approved Ebola vaccine is known to work against just one of them.

Objects can be 3D printed with light by projecting 2D computerized tomography (CT) scans onto rotating cylinders of resin, which solidify upon exposure.

How Amazon operates a 'flywheel' business model, a self-reinforcing cycle that drives continuous growth

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Iran's Revolutionary Guard Corps is independent of Iran's regular army and is one of the most powerful and influential military-political organizations in the Middle East.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

Waves off the coast of Nazaré, Portugal, can reach over 100 feet and are caused by the area's deep underwater canyon geography

Crows are believed to have intelligence on par with a seven-year-old child and demonstrate complex behaviors, from problem-solving with tools to recognizing human faces.

A small portion of The Winstons' 'Amen, Brother,' an obscure '60s gospel record, is the basis for thousands of hip-hop tracks, making it one of the most sampled records ever that's informally known as 'the Amen break.'

Double world record holder Hunter Ewen helped conquer his fear of balloons, called globophobia, by training to win Guinness World Record titles for balloon inflation.

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

The 19th-century painters of the Hudson River School were among the first American romantics, with portraits that displayed the natural beauty of the young country.