Air temperatures inland after the sea breeze begins may drop by as much as 9 F

Air temperatures inland after the sea breeze begins

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Air temperatures inland after the sea breeze begins, may drop by as much as 9 0 F – 18 0 F (5 0 C – 10 0 C) . But the effect generally reaches only 60 miles (100 km) inland in the Tropics , and half that distance in the middle latitudes. Sea breezes usually begin just before noon, and reach their greatest intensity (about 6 – 12 miles/hour or 10 – 20 km/hour) in the mid-afternoon . Sea breezes affect the amount of cloud cover and rainfall along coastal areas . (Florida convergence as one example. This convergence gives Florida a summer rainfall maximum.) Similar lake breezes exist along the shores of the Great Lakes.
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Mountain and Valley Breezes Daytime Air along mountain slopes is heated more intensely than air at the same elevation over the valley floor. (Creates low pressure.) During the high sun season, when solar heating is intense, warmer air glides up along the mountain slope , from higher pressure in the valley to lower pressure on the mountain slopes, generating a valley breeze . These upslope breezes generate isolated cumulus clouds over the adjacent mountain peaks. They cause common late afternoon thunderstorms on warm, summer days. Valley breezes are most common during the warm season when solar heating is most intense.
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Nighttime After sunset the pattern is reversed . Rapid radiation heat loss along mountain slopes cools the air. Air pressure rises along the mountain slopes. This cool air drains into the valley below and causes a mountain breeze ; mountain breezes are common during the cold season . Coldest pockets of air are usually found in the lowest spots . Low lying areas consequently are the first to experience radiation fog and are the most likely spots for frost damage to crops .
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Chinook (Föhn) Winds As the air descends, the leeward slopes of the mountains (especially in the Rockies and the Alps), it is heated adiabatically (by compression). Descending air is warmer and drier on the leeward side than at a similar elevation on the windward side. The temperature of these chinook winds is generally less than 50 0 F (10 0 C). But they occur in winter and spring when the affected area may be experiencing subfreezing temperatures. The dry, warm chinook winds bring drastic change . Within minutes the temperatures may climb 36 0 F (20 0 C) . These winds are snow eaters according to Native Americans. Granville, ND (21 February 1918), temperature rose from -33 0 F to +50 0 F, a rise of 83 0 F, as a result of chinook winds.
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Chinook Winds in Great Falls, Montana Great Falls, Montana is on the eastern side of the Rocky Mountains. It experiences chinook winds on 40 days per year on average. Santa Ana Winds in Southern California These are a type of chinook wind , and these hot, dry, desiccating winds greatly increase the threat of fire in this already dry part of the country. They are initiated by a strong anticyclonic (high pressure) flow in the Great Basin.
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Case Study of Southern California and Santa Ana Winds (Fall, 2003) at least 35 people killed over 9000 homes destroyed San Diego Chargers football game relocated to Arizona very unhealthy air quality Factors Behind It :
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  • Fall '16
  • Mark Smith
  • weather, Tropical cyclone, Atmospheric dynamics

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