Cut-Off Low Creates an Awesome Pinwheel of Dry Air Over the Southeast

A large low pressure system sitting over the southeastern United States is creating quite the sight on satellite imagery this afternoon as it wraps dry air into its core. This is a water vapor image from the GOES satellite, showing the moisture in the atmosphere around 10,000 feet up. Warmer colors indicate drier air, and cooler colors indicate moist air.

This same system is responsible for producing 6+ inches of rain over parts of Alabama and Georgia yesterday as it slowly passed through to the east. Light to moderate rainfall is spreading over most of North Carolina this afternoon, making for one miserable Saturday for millions of people.

Cut-Off Low Creates an Awesome Pinwheel of Dry Air Over the Southeast

This weather system is known as a "cut-off low." During the day yesterday, the low pressure system got cut off from the jet stream, leaving it spinning all alone in the southeastern United States with very little steering to move it out and no mechanism to help it strengthen.

Since there's nothing there to strengthen it, the low is essentially spinning to a slow death — it'll slowly move east out into the Atlantic and dissipate by Monday.

[Images via NASA and TwisterData]