Aerial ice observation flights supplemented the activity of the 

 surface patrol vessel during the period of this cruise as follows : 

 On 5 May two flights covered the area from the eastern edge of the 

 Grand Banks to an eastern limit defined by lines from the Tail of 

 the Banks to W N., 45° W., to 46 N., 44 :30' W., to 46 ' N., 46 W., 

 to 46'30' N., 46 W., thence west to the Grand Banks. On 15 May 

 three flights gave a complete ice census in the area south of the 

 50th parallel from the Newfoundland coast to 50" N., 45'' W., to 

 49- N., 43M5' W., to 46 45' N., 43 45' W., to 45°40' N., 46" W., 

 to 45=40' N., 49^ W., to Cape Race. 



fifth Cfi/ise, 'Modoc, ' 15 May to 29 May, 1946 



On 14 May 1946, at 1130 G. c. t., the Modoc departed Argentia, 

 Newfoundland, on ice patrol. At 0920 G. c. t. on 15 May, 1946, the 

 Modoc met and relieved the Tam-pa as surface patrol vessel at 

 45^00' N., 50 51' W. 



A general summary of the weather during the period of this 

 cruise follows. Five weak low-pressure areas or troughs affected 

 weather in the area. Two of the disturbances contained indefinite 

 occluded fronts that passed the Modoc. The passage of these fronts 

 was accompanied by precipitation of short duration. The periods 

 between the passage of the low pressure systems was characterized 

 by heavy fogs for protracted periods. Winds were mostly southerly 

 with the approach of the low pressure areas, becoming mostly 

 westerly with a rising barometer. The wind was steady at force 3 

 or 4 throughout the cruise except for an increase to force 6 with 

 the approach of an occluded front on the 18th. Air temperatures 

 ranged from an average daily minimum of 44 "F. to an average 

 daily maximum of 54 ^F. Passage of the five low-pressure systems 

 occurred on 18, 20, 23, 27, and 28 May. Passage of the occluded 

 fronts occurred on the 18th and 28th. Heavy fogs occurred on 18, 

 20, 21, 23, 26, 27, and 28 May. Clear and partly cloudy days fell 

 on 15, 17, 24, and 25 May. The 16th, 19th and 22d were cloudy 

 days. The lowest pressure, 1,011 millibars, occurred on the 28th. 

 Seas were relatively smooth during the entire cruise. 



At 2000 G. c. t.^on 29 May, 1946, at 43'^35' N., 53^5' W., the 

 Tampa relieved the Modoc which then set course for Argentia, New- 

 foundland, arriving there on 30 May 1946. 



Following is a summary of the water temperature, ice, and 

 obstruction reports received during this cruise: 



Number of ice reports received . 90 



Number of vessels furnishing ice reports 55 



Number of water temperature reports received 813 



Number of vessels furnishing water temperature reports .. 218 



Number of obstruction reports received 12 



Number of vessels furnished special information 21 



137 



