approximately 70 kilometers southeast of the survey area. However, 

 data collected by Sandy Hook Marine Laboratory (U.S. Department of 

 Interior, 1967) during a flight on 27 February show a tongue of warm 

 water extending northwestward from the Gulf Stream to the general 

 vicinity of the survey area. These data, with the outline of the 

 survey area superimposed on them, are reproduced as figure 13. 



Eleven flights across the boundary between the warm water and 

 the surrounding cooler water in the southeast portion of the survey 

 area shew a mean temperature gradient of 0.8°C/km, a minimum of 

 0,3°C/km, and a maximum of 2,5°C/km. Since the flight tracks may 

 not be normal to the boundary, the actual gradients may be greater. 

 The mean temperature difference across the boundary was 2.2*'C, with 

 a minimum of LS'^C (twice) and a maximum of S.S^C. Maximum observed 

 SST was 15.1°C (26 February). 



The greatest SST change (AT) during the survey occurred in the 

 warm-water area in the southeast portion of the survey area. The 

 combination of an increase in SST to the north of the zero AT iso- 

 pleth (figures 8-9) and a decrease in SST to the south of the zero 

 AT isopleth implies northward movement (advection) of the warm 

 water. 



Cooling occurred along the coast and in an area extending 

 seaward from the coast between Cape Henry and False Cape during 

 Phase I (figure 8) when gale winds and subfreezing temperatiire pre- 

 dominated. Waraing was evident in the same areas between surveys 

 under conditions of decreased winds and increased air temperatures 

 (figure 9). Mean SST was computed at various stations during warm 

 and cold periods to determine if temperature changes in the tongue 

 reflected changes in Chesapeake Bay, During the cold period (25 

 February to 2 March) temperature in Chesapeake Bay (Gloucester 

 Point) and at the entrance to the bay (Kiptopeke Beach) averaged 

 more than 2''C lower than the temperature at Chesapeake Light Sta- 

 tion. Temperatures in the tongue decreased as much as 2*'C during 

 this period. Conversely, the temperature in the bay and at the 

 entrance to the bay was slightly higher than the temperature at 

 the light station during the wanner period Cf-ll March). The in- 

 crease in mean temperature during the interval between cool and 

 warn periods was 3.8*»C in the bay, 4.9*»C at the entrance to the 

 bay, and l.S^c at the light station. Temperature changed in the 

 toigue as much as +3*^C during the same period. 



During initial occupation of the stations, negative tempera- 

 ture gradients in the near-surface layer were underlain by slightly 

 positive gradients to the bottom. Meteorological conditions fav- 

 ored surface heating during this period with skies either clear or 

 with scattered cirrus clouds, air temperature greater than SST, and 

 easterly winds less than 6 m/sec. Conditions favorable to surface 

 heating deteriorated prior to reoccupation of the stations as (1) 



