PAG-ASA has released its 3rd Advisory on the El Nino Phenomenon in May 6, 2015. The outlook for Batangas province remains the same: it will continue to experience a dry spell situation consisting of three (3) consecutive months of below normal rainfall condition. Still, although it is hoped that Batangas province’s situation will improve, the prevalence of the El Nino Phenomenon in the Pacific Ocean until the middle of the year 2015, with chances of strengthening towards the end of the year, could affect our water sources in the province. Because of this, it is advised that customers conserve water and store water. Watch out for our next post on the tips to conserve water.
06 May 2015
EL NIÑO ADVISORY NO. 3
Weak El Niño condition is still present in the tropical Pacific Ocean. Warmer than average sea surface temperature anomaly (SSTA) of at least 0.5°C has been observed since October 2014. Recent analyses from global climate models suggest that the on-going El Niño condition will likely to continue until mid-2015 with chances of strengthening toward the end of the year.
In April, the weather systems that affected the country were the northeast (NE) monsoon, ridge of high pressure areas (HPAs), easterlies, low pressure areas (LPAs) and the passage of one tropical cyclone named Typhoon (TY) “Chedeng” (April 2-5) which made a landfall over the coastal areas of Isabela but subsequently dissipated into an LPA as it moved towards mainland Cagayan Valley.
Rainfall assessment from December 2014 to April 2015 showed that several areas of the country were affected by either drought or dry spell. Drought is defined as three (3) consecutive months of way below normal (>60% reduction from average) rainfall condition. The drought-affected provinces were as follows: Luzon (Abra, Apayao, Ilocos Norte, Ilocos Sur, La Union, Mountain Province, Palawan, Pampanga), Visayas (Bohol), and Mindanao (Agusan del Norte, Basilan, Camiguin, Sulu, Tawi-tawi, Zamboanga del Norte).
Meanwhile, dry spell is characterized by three (3) consecutive months of below normal (21%-60% reduction from average) rainfall condition. Provinces affected by dry spell include the following: Luzon (Albay, Bataan, Batangas, Bulacan, Cavite, Masbate, Nueva Ecija, Sorsogon), Visayas (Biliran, Eastern Samar, Negros Oriental, Samar, Southern Leyte), and Mindanao (Agusan del Sur, Bukidnon, Compostela Valley, Davao del Norte, Lanao del Norte, Lanao del Sur, Leyte, Maguindanao, Misamis Occidental, Misamis Oriental, Sarangani, Siquijor, South Cotabato, Surigao del Norte, Sultan Kudarat, Surigao del Sur, Zamboanga del Sur).
Slightly warmer than average air temperatures were observed in Mindanao, eastern Visayas, and Metro Manila while near to slightly cooler than average air temperatures were observed over the rest of Luzon and Visayas. The highest daytime temperature in the country was observed in General Santos at 38.4°C (April 6) while the warmest nighttime temperature was recorded in Sangley Point at 28.1°C (April 30). In Science Garden (Quezon City), the recorded highest daytime and nighttime air temperatures are 36.2°C (April 18) and 27.2°C (April 20), respectively.
The month of May marks the weakening of the easterlies and gradual start of southwest monsoon wind. The onset of the rainy season is expected in mid-June. Other weather systems that are likely to affect the country for May are the intertropical convergence zone (ITCZ), easterlies, LPAs, ridge of HPAs, and one (1) or two (2) tropical cyclones to enter the Philippine Area of Responsibility. Afternoon or early evening thunderstorm activities are also expected to increase during the period.
Rainfall for the month of May are likely to be near normal over the Cordillera Administrative Region (CAR), Cagayan Valley Region, Northern Mindanao, CARAGA, and Autonomous Region of Muslim Mindanao (ARMM) while the rest of the country may experience below normal rainfall conditions. It is expected that forty-one (41) provinces will receive enough rainfall that may improve the existing dry conditions, four (4) may still experience extended dry conditions and one (1) province where dry spell will likely develop. For a complete list of these provinces, please refer to Drought/Dry Spell Outlook map.
Air temperatures are predicted to decrease in May in most parts of the country. Forecast average range of temperatures will be as follows: 23°C to 36°C in Lowland Luzon, 16°C to 25°C in the mountainous areas of Luzon, 23°C to 34°C for Visayas, 23°C to 34°C in the lowlands of Mindanao and 18°C to 31°C in the mountainous areas of Mindanao.
PAGASA will continue to closely monitor the on-going weak El Niño condition and updates shall be issued as appropriate. Meanwhile, concerned agencies are advised to take precautionary measures to mitigate its potential adverse impacts. For further information, please contact the Climatology and Agrometeorology Division (CAD) at telephone numbers 434-0955 or 435-1675.
VICENTE B. MALANO, Ph.D.