Criteria for High Wind Warning
A High Wind Warning is sustained surface winds exceeding 40 mph (≥35 kts) for at least 1 hour; or any gusts exceeding 58 mph (≥50 kts) , predicted or occurring for an unspecified period of time.…
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Criteria for High Wind Advisory
A High Wind Advisory is sustained surface winds 31-39 mph (27-34 kts) for at least 1 hour; or any gusts to 46-57 mph (40-49 kts), predicted or occurring for an unspecified period of time. More Weather Glossary…
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What is the Beaufort Wind Scale?
The Beaufort Wind Scale (BEW-fert scale) or sometimes called The Wind Intensity Scale: is used to estimate wind speeds based on observation of objects in relationship to the wind. This method of measuring wind speed was…
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What is a Tropical Cyclone?
A Tropical Cyclone - generically describes a low pressure system that typically forms in the tropics. A collection of strong thunderstorms makeup a cyclone, and in the Northern Hemisphere, surface winds rotate counterclockwise. In the North…
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iAlert.com Newsletters
This page keeps track of iAlert.com newsletters. Newsletters are sent 4-5 times per year to inform iAlert members of feature/functionality updates and/or to communicate important service information. June 2014 Premium Service Update 2014 Supporting iAlert.com Campaign…
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Local Storm Reports on iAlert.com
A Local Storm Report (LSR) is an event driven storm damage and observational report issued by the National Weather Service (NWS). These reports are submitted to the local NWS office by trained storm spotters, amateur radio…
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What is a Derecho?
A Derecho (deh REY cho), or sometimes called a "Bow Echo" due to the bent curve of the radar signature, is a wide spread, long-lived, line or cluster of strong thunderstorms, that rapidly moves east or…
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