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Tornado Watch:
Conditions are conducive to the development of tornadoes in and close to the watch area.

Tornado Warning:
A tornado has actually 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 actually been observed by spotters or indicated on radar, and is occurring or imminent in the warning area.

Flood Watch:
High flow or overflow of water from a river is possible in the given time period. It can also apply to heavy runoff or drainage of water into low-lying areas. These watches are generally issued for flooding that is expected to occur at least 6 hours after heavy rains have ended.

Flood Warning:
Flooding conditions are actually occurring or are imminent in the warning area.

Flash Flood Watch:
Flash flooding is possible in or close to the watch area. Flash Flood Watches are generally issued for flooding that is expected to occur within 6 hours after heavy rains have ended.

Flash Flood Warning:
Flash flooding is actually occurring or imminent in the warning area. It can be issued as a result of torrential rains, a dam failure, or ice jam.

Winter Storm Watch:
Severe winter conditions, such as heavy snow or ice, are possible within the next day or two. Prepare now! 

Winter Storm Warning:
Severe winter conditions have begun or are about to begin in your area. Seek shelter!

Blizzard Warning:
Snow and strong winds will combine to produce a blinding snow (near zero visibility), deep drifts, and life-threatening wind chill. Seek refuge immediately! 

Winter Weather Advisory: 
Winter weather conditions are expected and may be hazardous, especially for motorists. 

Frost/Freeze Warning:
Below freezing temperatures are expected and may cause significant damage to plants, crops, or fruit trees. In areas unaccustomed to freezing temperatures, people who have homes without heat need to take added precautions.