Scattered strong to severe storms, excessive rainfall, and flooding are expected across parts of the Mid-Atlantic into the Northeast today. Flood Watches are in effect. Heat will continue to impact the West today. Heat advisories are in effect for portions of the Intermountain West; and Extreme Heat Warnings are in effect for portions of Arizona and southeast California. Read More >
Other Domains: Baxter S.P. | Marine/Coast | Northern/Eastern Maine
Wet Bulb Globe Temperature (WBGT) is a measure of the heat stress in direct sunlight, which takes into account: temperature, humidity, wind speed, sun angle and cloud cover (solar radiation). This differs from the heat index, which takes into consideration temperature and humidity and is calculated for shady areas. For more background info on WBGT, click here.
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Risk Level
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Definition
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None
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No lightning risk
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Limited
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Thunderstorms expected to be isolated in coverage.
Atmospheric conditions support cloud to ground lightning strikes in and near thunderstorms. Be aware for thunderstorms in your area. |
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Elevated
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Thunderstorms expected to be scattered in coverage.
Atmospheric conditions support cloud to ground lightning strikes in and near thunderstorms. Be prepared to take immediate shelter from thunderstorms and lightning. |
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Significant
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Numerous thunderstorms are expected.
Atmospheric conditions support cloud to ground lightning strikes in and near thunderstorms. Plan to take immediate shelter from thunderstorms and lightning. |
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Extreme
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Widespread thunderstorms are expected.
Atmospheric conditions support cloud to ground lightning strikes in and near thunderstorms. Plan to take immediate shelter from thunderstorms and lightning. |