The weight of the column of air that extends from the ground (or water's surface) to the top of the atmosphere. It is also called air pressure. Barometric pressure is very low in a hurricane.

The patterns of wind flow that work together to create conditions in which severe weather can form.

A closed, rotating wind. Cyclones rotate counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

A radar that compares in frequency, up or down from the original signal, echoes returned from weather systems to create highly-accurate measurements of the weather system's velocity.

A storm that forms outside the tropics, sometimes as a tropical storm or hurricane changes.

The low pressure center of a hurricane. Winds are normally calm and sometimes the sky clears.

The ring of thunderstorms that surrounds a storm's eye. The heaviest rain, strongest winds and worst turbulence are normally in the eye wall.

Flash flooding conditions could pose a threat. You should decide which valuables you may need to move and how your family can escape the area

Flash flooding conditions are imminent. Immediate action should be taken to protect your family and property.

Sustained surface winds between 39 mph and 54 mph are reported or predicted.