caused by well-developed sea breeze conditions, transport sea fogs and 

 moisture inland. They also deposit salt over land. While sea breezes can 

 only penetrate about 10 miles (16 km) inland, storms can transport salt much 

 farther. Stronger south winds are less frequent. 



Fall wind patterns resemble the annual average. Portland and Old Town retain 

 their western compass predominance, while some channeling modification is 

 present at the other locations. 



Fog. Fog is prevalent along the coast of Maine and diminishes in 

 frequency of occurrence with distance inland. Thirty-year records at Eastport 

 and Portland show that heavy fog (visibility <0.25 miles ;< 0.4 km) occurs with 

 a frequency of 60 and 52 days/year respectively (U.S. Department of Commerce, 

 NOAA, irregular ) . Data on Augusta are availble for only a 3-year period. A 

 15-day/year average is observed there. When the data are analyzed by season, 

 the extreme eastern and western locations of Eastport and Portland are found 

 to have similar frequencies in all seasons except summer, when Eastport 

 reaches a high of heavy fog on 1 day in 3 and Portland 1 day in 5. The season 

 for lowest fog frequency is winter, when heavy fog averages only 5 to 6 days. 



Additional data at the U.S. Coast Guard foghorn stations along the coast 

 between the periods for 1950 to 1969 support the fog frequency observations at 

 Eastport and Portland. These stations are listed in table 2-3 and their 

 locations ar shown in figure 2-12. By law, the foghorns are required to 

 operate whenever visibility in adjacent waters is <3 miles (< 5 km). These 

 stations regularly log their hours of operation and a summary of their hours 

 of operation is used to compute hourly fog frequencies. The records of 

 foghorn stations in the characterization area are averaged by region in figure 

 2-13 (stations 1 to 4 are combined under region 6; stations 5, 7, 8, and 9 are 

 combined under region 5; stations 11, 12, and 14 are combined under region 4; 

 station 15 alone represents region 3; stations 16 and 17 are combined under 

 region 2; and 19 to 22 under region 1.) Hourly data on fog frequency along 

 the coast are similar for fall, winter and spring, varying from 10% to 13% 

 (about 1 hour in 10). In summer, however, fog incidence rises sharply, 

 doubling in regions 1 through 4 and almost tripling in region 6. The hourly 

 fog frequency along the coast of region 6 climbs to nearly 1 hour in 3 (33%) 

 in summer. 



Inland fog frequency data exhibit much more variation. A high incidence of 

 fog follows the major waterways inland, but as the land mass broadens, fog 

 becomes intermittent. Wetland areas foster local fog generation, as well as 

 lengthen the duration of larger fogs. 



Snow . The average annual snowfall along the coast varies from a low of 

 60 inches (152 cm) at Rockland to a high of 97 inches (246 cm) at Bangor (U.S. 

 Department of Commerce, NOAA, irregular ) . The low annual snowfall near the 

 coast (Rockland) in comparison with that at the inland boundary of the 

 coastal zone (Bangor) is the most graphic example of a trend that is apparent 

 throughout the coast. 



Data on average snowfall are summarized in figure 2-14. The three stations 



closest to the coast are those with the three lowest snowfall amounts: 



Eastport, Bar Harbor, and Rockland. Differences among the remaining stations 

 appear to be the result of local characteristics and distance inland. 



2-23 



10-80 



