Watches and Warnings
National Weather Service (NWS) Products
Not sure when certain National Weather Service (NWS) products are issued? Look below...
 
When NWS Products are Issued
 

Severe Thunderstorm Warning: Issued when severe weather has been identified on Doppler Weather Radar or reported by someone in or near the storm(s)...such as a trained storm spotter. With a warning in effect, penny size hail or larger and/or damaging winds (58 mph or greater) are expected.

Tornado Warning: Issued when a tornado has been identified on Doppler Weather Radar or reported by someone in or near the storm(s)...such as a trained storm spotter. With a warning in effect, a tornado is expected and may be accompanied by other severe weather such as dime size hail or larger and/or damaging winds (58 mph or greater).

>>>Note<<<

Severe Thunderstorm Warnings and Tornado Warnings should not be confused with Severe Thunderstorm Watches or Tornado Watches. The Watches imply that severe weather is possible but not imminent...and are posted to give people time to prepare for severe weather should it materialize. The Warnings take matters one step further, and imply that severe weather is imminent.

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Flash Flood Watch: Issued when conditions are favorable for flash flooding...with excessive rain possible but not imminent. By excessive, it is meant that rainfall rates exceed what the ground can hold...with water running from the ground into creeks and streams and across roads.

Flash Flood Warning: Issued when excessive rain has occurred...with flash flooding imminent. With a warning in effect, people are urged to leave areas near rapidly rising creeks and streams...and are advised not to cross roads covered by water.

Flash Flood Statement: Issued to update conditions when a Flash Flood Watch and/or Warning is in effect...or when mainly urban flooding (i.e. street flooding) is expected or is occurring (issued as an "Urban and Small Stream Flood Advisory"). A Flash Flood Statement is also issued to cancel all or part of a Flash Flood Warning.

Hazardous Weather Outlooks: Issued at least once a day (around 5 am), and advises people of possible hazardous conditions in the next 7 days. Hazards include severe thunderstorms, winter weather, non-precipitation events (i.e. strong winds, excessive heat, dense fog, etc.), extremely dry conditions (i.e. leading to fires) and flooding.

Special Weather Statements: Issued mainly as a "Significant Weather Alert" for storms that are below severe limits (less than penny size hail/wind gusts under 58 mph). This product is also used to inform people of a significant weather event expected to affect the region in the near future.

Severe Weather Statements: Issued to help people monitor severe weather trends when a Severe Thunderstorm or Tornado Warning is in effect, with descriptions of storm location and what the storm has produced (i.e. large hail, damaging winds, etc). The Severe Weather Statement is also used to cancel warnings when storms have weakened.

Watch County Notification Message: Issued to indicate what counties are affected by a Severe Thunderstorm or Tornado Watch. This product is also used to clear counties once severe weather has passed.

Winter Weather Message: Issued when hazardous Winter weather is possible (i.e. Winter Storm Watch) or imminent. When hazardous Winter weather is imminent, the message may cover a variety of conditions depending on what is expected. Warnings usually imply that heavy snow (at least 4 inches in 12 hours/6 inches in 24 hours) and/or ice (significant accumulations) are expected, with travel not recommended. Advisories imply that lesser snow and/or ice are expected, with perhaps some travel delays resulting.

Non-precipitation Message (Weather Message): Issued when significant non-precipitation events are expected, such as dense fog (or freezing fog), high winds, extreme wind chills/heat index values, and freezes during the growing season. 

 

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