24 May 2017
START OF SOUTHWEST MONSOON
Southwesterly windflow has been dominant over the West Philippine Sea for several days now. This is due to the formation of semi-permanent trough over Northern Luzon-Taiwan area and the eastward migration of the North Pacific High Pressure Area which are the prominent indicators of the southwest monsoon onset in the country.
Likewise, the prevailing weather condition in most parts of Luzon and Visayas particularly the western section is now warm and humid as characterized by occasional to frequent occurrences of afternoon-evening or early morning rainshowers and thunderstorms. These developments signify the approaching onset of rainy season under Type 1 climate covering the western parts of Luzon and Visayas.
It is expected that during the remaining days of May light to moderate rainshowers and isolated thunderstorms will prevail. However, it may be followed by short dry period called monsoon break. Occasional to frequent rains and thunderstorms in most parts of Luzon and Visayas will be experienced in the coming months due to southwest monsoon activity.
PAGASA will continue to monitor the weather condition and updates will be issued as appropriate.
For more information, you may contact the Weather Division at telephone numbers (02) 927-1335 and 927-1541.
VICENTE B. MALANO, Ph.D.