by a weak low on the 28th, Severe weather conditions continued in 

 the survey area until 2 March as a result of a high located over the 

 the Great Lakes and a low located over Nova Scotia, Movement of 

 the high over Cape Hatteras on 3 March resulted in southerly winds 

 and wanner air in the survey area. The weather remained relatively 

 mild through 7 March despite the passage of several weak lows. Air 

 temperature decreased to near freezing, and gale winds occurred 

 after passage of a cold front early on 8 March, Weather conditions 

 moderated rapidly and remained good until after the completion of 

 Phase II on 11 March, 



Mean air temperature and SST at Chesapeake Light Station and 

 the difference between the two are given in table 1 for Phases I 

 and II and for the 9-day interval between phases. Mean SST for the 

 period between 1956 and 196U (from annual data, various authors, U,S» 

 Department of Interior) is included for reference, A warming trend 

 following the cold outbreak during Phase I is apparent. The nega- 

 tive air-sea temperature difference during the cold period indicates 

 heat loss to the atmosphere. The degree of atmospheric warming 

 which occurred thereafter is shown in a plot of air tenperature 

 and wind velocity at the light station for the period 23 February to 

 13 March (figure 12), 



Table 1 

 Mean Temperatures at Chesapeake Light Station (°C) 



Period 



Phase I 

 Interval 

 Phase II 



Air Temp. 



-l.so 



+7,3 



+8,9 



SST 



+U,30 



+5.4 



+6.5 



Difference 



-5,6 

 +1,9 

 +2,«* 



Historical 

 SST 



+1,9 

 + 5,5 

 +6,2 



DISCUSSION 



SST patterns observed during the survey generally resembled 

 previous analyses based on ship observations. The zonal tempera- 

 ture gradient was computed to be CS^C/km using data recorded dur- 

 ing eight ART flights near 370N between 74,5«> and 75,70W during 

 the period from 23 February to 10 March, Minimum and maximum SST's 

 near the inshore boundary of the survey area (Chesapeake Light Sta- 

 tion) were 3,30C (26 February) and 7,30C (10-11 March), 



The warm water observed in the southeast portion of the survey 

 area may be (1) a warm eddy similar to one observed by Ichiye (1966) 

 or (2) a warm tongue projecting from the Gulf Stream. A Gulf Stream 

 flight by the ASWEPS aircraft on 1 March located the north wall 



