GO 



J. Eliot — The South-West Monsoon Storms 



[No. 2, 



Table of Daily Amount of Wind at seven Stations to the east of the Bay. 

 July 22nd to 2Sth, 1883. 



Average 

 June. 



22nd. 



23rd. 



24th. 



25th. 



26th. 



27th. 



28th. 



Nancowry 



Port Blair 



Diamond Island. 



Akyab 



Chittagong 



Sanger Island 

 Dacca 



263-5 

 257-6 

 203-0 

 93-6 

 168-3 

 332-4 

 183-7 



115-0 



128-7 

 122-9 

 42-7 

 162-6 

 362-7 

 211-1 



98-8 

 212-9 

 118-5 



48-9 

 113-5 

 312-4 

 181-1 



97-3 



3860 



118-7 



55-4 



72-9 

 284-7 

 142-8 



124-2 



283-8 

 240-7 

 83-6 

 71-9 

 235-2 

 155-0 



252-7 

 305-4 

 310-4 

 100-9 



50-1 

 144-5 



68-8 



354-5 

 315-6 

 346-6 

 153-8 

 117-7 

 1371 

 66-8 



289-8 

 323-0 

 336-5 

 234-4 

 212-2 

 357-4 

 181-1 



The preceding table shows that on the 22nd and 23rd the winds 

 were barely half their normal strength over the east of the Bay. A 

 rapid increase took place on the 24th at Port Blair, which extended to 

 Diamond Island on the 25th and to Akyab and Chittagong on the 26th 

 and 27th. 



These figures suggest what is also indicated by the whole of the 

 Bengal observations, viz., that the weather in the Bay between the 20th 

 and 23rd of June was that which usually accompanies the commence- 

 ment of a partial break in the rains in Bengal or Northern India. Winds 

 were light and unsteady over the whole of the north and centre of the 

 Bay. The logs of vessels show that occasional rain-squalls local in 

 character occurred, more especially in the south of the Bay. The 

 observations at Port Blair, Nancowry, Diamond Island, and Akyab and 

 of the ships traversing the Bay at the time, however, prove conclusively 

 that south-westerly winds prevailed over the whole of the Bay ; and the 

 Bengal observations establish that they were continued in Bengal and 

 Behar as southerly and easterly winds. They also indicate that on the 

 24th a change occurred in the character of the winds to the west of the 

 Andamans which lasted for some days. A very considerable increase 

 occurred in the south-west winds of that part of the Bay which rapidly 

 and steadily extended northwards. 



Hence prior to the morning of the 25th the gradients were normal 

 in direction, although smaller in amount than the average for the season, 

 over the Bay ; the winds blew from the usual quarter and gave rise to the 

 normal atmospheric current up the Gangetic valley. The only indica- 

 tion afforded at this time by the land observations of the subsequent 

 stormy weather was the occurrence of a partial break in the rains, which, 

 as has been ascertained by previous experience, establishes conditions 

 which are favourable to the development of a cyclonic disturbance if an 

 adequate motive power or disturbance act on the atmosphere. 



