Geostationary Operational Environmental Satellite. A brief, sudden increase in wind speed with a fluctuation greater than 10 knots during a period less than 30 seconds. The boundary between air flowing into a thunderstorm and the precipitation-cooled air flowing out of the storm. A shelf cloud may be seen above its surface position. Frozen precipitation in the form of layered lumps of ice produced by convection within cumulonimbus clouds.
Fine dust particles present in a portion of the atmosphere.
Issued when the Heat Index is expected to exceed 105 during the day and 80 during the night for at least two consecutive days. In general, snowfall is accumulating at the rate of either 4 inches or more in 12 hours or less, or 6 inches or more in 24 hours or less. Large waves breaking on or near the shore resulting from swells spawned by a distant storm. An area of high pressure around which the wind blows clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. Generally the measure of the water vapor content of the air.