WEATHER 



Following the arrangement of reports in former years, there is set 

 forth under this section a description of the general weather conditions 

 that were experienced during the ice patrol of 1927. The remarks, 

 which are grouped according to months, are devoted to tracing the 

 general behavior of the high and low pressure systems in the atmos- 

 phere as they traveled over the eastern United States and passed 

 out to sea, across the ice regions. Accompanying the monthly 

 remarks is a sketch showing the tracks of the more noteworthy 

 disturbances, and also in other particular instances sketches have 

 been appended. The weather diagram for each month gives at a 

 glance the wind direction and force averaged for every 12 hours; the 

 barograph curve; and the time and duration of fog and low visibility 

 during the month. The geographical position, for which this is a 

 meteorological record, although observed from the patrol ship cruising 

 in the ice regions, can for all practical purposes and interpretations, 

 be taken as latitude 43° 00' N., longitude 50° 00' W., the Tail of 

 the Grand Banks. A general description of the two major types of 

 weather which prevail in the ice regions, remarks on the structure of 

 a storm, and iceberg forecasting by means of the weather are all 

 contained in the ice patrol report for 1926 (Bull. No. 15), to which 

 the reader's attention is invited. 



MARCH 



When the Tampa left Boston on March 22, a great mass of cold 

 dry air was spreading east and southeast out of central Canada, 

 across the North Atlantic States, the Maritime Provinces, and out on 

 to the ocean. A center of low pressure retreated before this invasion 

 leaving one vast area of high pressure enveloping the land and ocean 

 to the northward of us. The Tampa, because of such a distribution 

 of pressures, experienced continuous easterly winds on her passage 

 to the ice regions. Along the southeastern border of this afore- 

 mentioned air mass, from March 23 to 26, there traveled a low- 

 pressure disturbance. It was first observed on the meteorological map 

 for March 22 off the coast of the Carolinas, but after that it could not 

 be followed so clearly, due to the scarcity of ship reports from this 

 direction. Its path is shown fairly accurately, however, as track A 

 on Figure 2, the center passing close to the Tampa on the morning 

 of the 26th instant, when she was south of Sable Island. The first 

 effects of this storm (a depression of the barograph, see fig. 1) were 



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