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Answer: The jet stream can indeed be an important feature in marking the the evolution of upper level pressure patterns and can act as a steering feature for lower-level air masses and pressure systems, in addition to channeling smaller "jet streaks" that produce vertical motions that can cause clouds and precipitation to form or dissipate. The intensity, location and organization of the jet stream itself is influenced by the distribution of temperature, humidity and density of air at and below jet stream altitudes, which are in turn influenced by the temperature of land and water surfaces. The distribution and gradients of these temperatures, humidities and densities can also be affected by short-term, small to medium scale heating and cooling associated with condensation and evaporation of water in clouds and precipitation, and to large scale, slow-changing factors like the El Nino-Southern Oscillation. As you can see, it all sets up an interconnected, chicken and egg-like scenario (referred to in science as a "non-linear" system) in which the jet stream influences the movement and behavior of air masses and traveling storm systems, and is in turn itself influenced by that movement and behavior.
Oct. 31, 2009 | Tags: fronts & airmasses, general meteorology

Answer: A ridge in the atmosphere is an elongated area having barometric pressure greater than the pressure at the same elevation in most directions away from the ridge axis. On a weather map, ridges can be identified by a series of sharply curved isobars, with the isobars "pointing" toward areas of lower pressure, or by an area in which isobars stretch between two or more high pressure centers. The appearance of isobars on a weather map in these cases is analogous to the appearance of ridges in topography on a contour map of ground elevations.
Oct. 19, 2009 | Tags: fronts & airmasses, general meteorology

Answer: As is often the case in meteorology, there are notable exceptions to a broad generalization like this, but typically a surface high pressure center is associated with gently sinking air, which tends to result in fair skies, fairly low humidity and little or no precipitation. Low pressure centers, on the other hand, are usually regions in which air is forced upward, leading to the development of clouds and sometimes precipitation.
Oct. 14, 2009 | Tags: fronts & airmasses, general meteorology

Answer: It's more likely you're noticing the coincidental influence of some other weather features, namely a marine airmass boundary and/or a weak line of low pressure called the "Piedmont Trough" that are not influenced by the highway, but happen to align themselves in its vicinity with some frequency at certain times of the year. Both of these features are products of North Carolina's topography, its soil types, and the orientation of its coastline relative to the Atlantic Ocean.
Aug. 14, 2009 | Tags: fronts & airmasses, thunderstorms

Answer: That is an unusually large drop, but one idea is that the large black cloud may have marked an outflow boundary from a nearby thunderstorm, in which an evaporation-cooled downdraft spreads outward as something akin to a small scale cold front. This, together with the loss of solar radiation associated with the thick cloud moving overhead, can bring a sudden and significant temperature fall. It's also possible that water temperatures offshore were much cooler than land temperatures, and a wind shift advected water-chilled air into your location.
Jun. 16, 2009 | Tags: cold, fronts & airmasses