The Philippine Journal of Science 



Temperature alone would not give Baguio its fine climate, 

 but the fortunate distribution of rainfall or, rather, its concen- 

 tration in July, August, and September leave the rest of the 

 year balmy and pleasant, in marked contrast to Mount Banahao 

 where, with even lower temperature, the rainfall is distributed 

 throughout the year. Coronas in a note upon rainfall describes 

 general conditions as follows: 12 



There cannot be any doubt that the most interesting feature of the 

 climate of the Philippines is the monthly distribution of rainfall. If this 

 element would be about the same throughout the Archipelago, there Would 

 hardly be any difference of climate in the Philippines. But as it is, 

 the different position of the islands which makes them or part of them 

 more or less exposed to the general winds prevailing in the Philippines, 

 both in winter and in summer, is the principal cause of our different kinds 

 of climate in spite of the relatively small extension of the Archipelago 

 from east to west, especially in Luzon. In winter the rains of the Philip- 

 pines are mainly due to the northeasterly air currents, which, coming 

 directly from the Pacific, cause abundant rains to fall over the eastern 

 part of the Archipelago. Hence they are sometimes called "NE monsoon 



of typhoons which either cross the Islands, generally from eastsoutheast 

 to westnorthwest, or pass some distance to the north. These rains, 

 though quite general throughout the Archipelago, are more abundant 

 in Luzon and the Visayas, and exceptionally heavy at times in the western 

 part of these Islands which is more exposed to the westerly and south- 

 westerly winds. As the great majority of typhoons that occur from June 

 to October pass to the NE or N of the Philippines or cross the northern 

 part of Luzon, the winds from west and southwest are the most prevailing 

 during that season. This summer and autumn rainfall may be rightly 

 called "cyclonic rainfall" as distinguished from the "NE monsoon rainfall." 

 These cyclonic rains are far from being continuous, their frequency 

 depending entirely on the frequency of typhoons. 



Coronas recognizes four types of rainfall distribution. The 

 first type has two pronounced seasons, dry in winter and autumn. 

 The second type has no dry season with pronounced maximum 

 in winter. The third type is characterized by no very pro- 

 nounced maximum rain period and by a short dry season, from 

 one to three months in length, while the fourth type has no 

 maximum rain period and no dry season. Baguio has the 

 marked characters of the first type, as fig. 4 shows clearly. 



The great variation in the amount of the annual rainfall in 

 Baguio is shown graphically by fig. 5, from the Census. 13 Even 



12 Op. cit. 342. " Op. cit. 355. 



