The National Weather Service has issued tornado watch that remains in effect until 10 pm this evening for western and southern Connecticut, including Litchfield, Fairfield, and New Haven Counties, as well as neighboring Westchester and Putnam Counties in New York.

This watch is issued by the National Weather Service when conditions are favorable for the development of tornadoes in and close to the watch area. Their size can vary depending on the weather situation.

They are usually issued for a duration of 4 to 8 hours. They normally are issued well in advance of the actual occurrence of severe weather.

During the watch, people should review tornado safety rules and be prepared to move to a place of safety if threatening weather approaches.

Ready.gov advises residents to take the following preventative measures during a tornado watch:

Turn on your TV/radio - You’ll get the latest weather updates and emergency instructions.

Avoid unnecessary car trips - You don’t want to be caught outside if a tornado comes.

Bring in outdoor furniture and other items that could blow away - These may become a safety hazard.

Watch out for dark, rotating clouds - If you see one, take shelter immediately.