Maine's climate is controlled by the same factors that control the weather 

 over much of New England, but temperatures and humidities of coastal areas are 

 modified by air masses flowing from offshore waters. A particular location is 

 affected by its distance from the ocean, its elevation, and its terrain. The 

 latter factors create three natural weather zones: coastal, southern 

 interior, and northern. Maine is noted for its rapidly changing weather 

 conditions and its severe winters. 



The following are excerpts from a general discussion of Maine's climate by 

 Lautzenheiser (1972): 



Maine lies in the "prevailing westerlies" - the belt of 

 generally eastward air movement which encircles the globe 

 in the middle latitudes. Embedded in this circulation are 

 extensive masses of air originating in higher or lower 

 latitudes and interacting to produce storm systems. 

 Relative to most other sections of the country, a large 

 number of such storms pass over or near Maine. The 

 majority of air masses affecting this State belong to 

 three types: (1) cold, dry air pouring down from 

 subarctic North America, (2) warm, moist air streaming up 

 on a long overland journey from the Gulf of Mexico and 

 from subtropical waters eastward, and (3) cool, damp air 

 moving in from the North Atlantic. Because the 

 atmospheric flow is usually offshore, Maine is influenced 

 more by the first 2 types than it is by the third. In 

 other words, the adjacent ocean constitutes an important 

 modifying factor on the immediate coast, but does not 

 dominate the climate statewide. 



The procession of contrasting air masses and the 

 relatively frequent passage of storms bring about a 

 roughly twice-weekly alternation from fair to cloudy or 

 stormy conditions, attended by often abrupt changes in 

 temperature, moisture, sunshine, wind direction, and wind 

 speed. (However, there are) periods of time during which 

 the same weather patterns continue for several days, 

 infrequently for several weeks. (Consequently,) the same 

 month or season will exhibit varying characteristics over 

 the years - sometimes in close alternation, sometimes 

 arranged in similar groups for successive years. A 

 "normal" month, season, or year is indeed the exception 

 rather than the rule. .. .Hence , "weather averages" in Maine 

 usually are not sufficient for important planning purposes 

 without further climatological analysis. 



Coastal storms or "northeasters" sometimes seriously 

 affect the coast. They generate very strong winds and 

 heavy rain or snow, and they sometimes produce glaze or 

 "ice storm conditions." They can produce abnormally high 

 wind-driven tides, affecting beaches and coastal 

 installations. In winter, these storms produce some of 

 the heavier snowfalls along the coast. Occasionally, in 

 summer or fall, a storm of tropical origin affects Maine. 



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