Severe Thunderstorm Watch – Conditions are favorable for the development of severe thunderstorms in and close to the watch area. A severe thunderstorm contains large damaging hail of 1 inch diameter or larger, and/or damaging winds greater than 58 mph
Severe Thunderstorm Warning – A severe thunderstorm is indicated by Doppler weather radar or sighted by Skywarn spotters or other persons, such as local law enforcement. A severe thunderstorm contains large damaging hail of 1 inch in diameter or larger and/or damaging winds of 58 mph or greater.
Significant Weather Advisory – A strong thunderstorm is indicated by Doppler weather radar, containing small hail below 1 inch diameter, and/or strong winds of 39–57 miles per hour
Tornado Watch ― A tornado watch is issued when weather conditions are favorable for the development of severe thunderstorms that are capable of producing tornadoes. A tornado watch therefore implies that it is also a severe thunderstorm watch.
Tornado Warning ― A tornado warning is an alert issued by national weather forecasting agencies to warn the public that severe thunderstorms with tornadoes are imminent or occurring. The issuance of a tornado warning indicates that residents should take immediate safety precautions.
Flash Flood Watch – Conditions are favorable for flash flooding in and close to the watch area. These watches are issued by the Weather Forecast Office and are usually issued six to 24 hours in advance of expected flood potential.
Flash Flood Warning – Flash flooding is occurring, imminent, or highly likely. A flash flood is a flood that occurs within six hours of excessive rainfall and that poses a threat to life and/or property. Ice jams and dam failures can also cause flash floods. These warnings are issued on a county by county basis by the local Weather Forecast Office and are generally in effect for two to six hours, although particularly during tropical cyclones a warning may last for a longer period of time, and occasionally last shorter than two hours
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