QNH
#21
As for the high at the equator, while the LARGE (Global) scale weather pattern depicts an average lower pressure at the surface (due to the ITCZ), the equator still gets highs and lows, warm and cold fronts, and other synoptic and local scale weather events so high pressure areas can occur at the equator however the most prominent pressure system at the equator is a low pressure due to heating, convergence, and the resultant lifting action. Earth's rotation and the thickness of the atmosphere at the equator do not really contribute to the equatorial low pressure (THAT MUCH!! They do contribute to global scale weather patterns considerably, but not for this specific topic)
#22
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Joined APC: Jul 2014
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Thanks for throwing a light down here Fly_Boy_Knight
Another question came to my mind. Can you anticipate a "bad weather" which is associated with low pressure with just getting a low QNH from ATC? And stable weather when QNH is high?
Another question came to my mind. Can you anticipate a "bad weather" which is associated with low pressure with just getting a low QNH from ATC? And stable weather when QNH is high?
#23
A good example is Florida in the summer. Pressure is typically higher than standard all summer, day and night, however because of the daily heating and converging sea breezes during the day, thunderstorms develop like clockwork every afternoon in otherwise-stable air / high pressure air. This is another example of how local (mesoscale) weather patterns can overpower larger (synoptic) scale weather patterns.
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