Severe Weather Definitions...defined
(including Watches and Warnings)


The National Weather Service uses specific terminology to relay the weather threat to the public. In the summer, there are a variety of watches and warnings you need to understand in order to be prepared:

Tornado Watch: Means that conditions are favorable for tornadoes to develop. It is normally issued for 4 to 6 hours, and includes many counties. If you are in or near the tornado watch area, stay informed via NOAA Weather Radio, commercial radio or television. Keep your eye on the sky, and be prepared to take cover at short notice, as tornadoes can occur with little or no warning.

Tornado Warning: Means that a tornado has been sighted, or a developing tornado is reported by trained spotters or indicated on Doppler radar. A warning is typically issued for a small area for less than an hour. If a tornado warning is issued for your area...take cover immediately!

Severe Thunderstorm Watch: Means that conditions are favorable for thunderstorms to produce wind gusts to 58 mph or stronger or hail to 3/4 inch or larger in the watch area. These watches are issued for 4 to 6 hours at a time and for a number of counties. Stay informed, watch the sky, and take cover if a severe thunderstorm approaches you.

Severe Thunderstorm Warning: Means that a severe thunderstorm has been detected by radar, or by a trained spotter. Take cover if you are near the severe thunderstorm.

Flash Flood Watch: Issued when heavy rain may develop and result in flash flooding in or near the watch area.

Flash Flood Warning: Flash flooding in the warning area has developed or is imminent. Move to higher ground at once!

Urban and Small Stream Flood Advisory: Local flooding of small streams, streets, or low lying areas such as railroad underpasses is occurring or is imminent.

Hazardous  Weather Outlook: A product issued by local Weather Forecast Offices to discuss the significant weather of the day. For spotters and Emergency Managers this product will detail the type of severe weather expected, timing and expected location of the severe weather. The Denver Forecast Office issues this outlook around 6 am and 11 am each day under the header DENHWODEN.

Spotter Network Page Severe Weather Page Denver's Home Page

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