According to Weather.com:
Tornado watch — Conditions are conducive to the development of tornadoes in and close to the watch area.
Tornado warning — A tornado has been sighted by spotters or indicated on radar and is occurring or imminent in the warning area.
Severe thunderstorm watch — Conditions are conducive to the development of severe thunderstorms in and close to the watch area.
Severe thunderstorm warning — A severe thunderstorm has been observed by spotters or indicated on radar, and is occurring or imminent in the warning area.
Severe thunderstorms can produce tornadoes or cause damage from their strong wind gusts and/or hail.
Click on this link to find out more about what to do in case of a big storm/tornado
Emergency Information
Visit http://www.fairfaxcounty.gov/emergency/ for tips from that will help you keep safe and able to respond to changing events. In the event of an emergency, their emergency blog will be updated with breaking news and information.
- To sign up for the The Community Emergency Alert Network (Fairfax County Alert) click here. The Community Emergency Alert Network (CEAN) delivers important emergency alerts, notifications and updates during a major crisis or emergency, in addition to day-to-day notices about weather and traffic.
- To sign up for the Loudoun County alert system click here
Photo: Jimmy Baikovicius