Gale Warning
Issued at: 05:00 AM TODAY , 25 October 2020
Gale Warning # 23
For: STRONG to gale force WINDS ASSOCIATED with tropical storm "quinta" {molave} and THE SURGE OF NORTHEASTERLY SURFACE WINDFLOW.

Gale Warning in PDF file

Weather Advisory
Issued at: 10:00 AM 2020 October 23
Weather Advisory in PDF file

General Flood Advisories - Regional
 General Flood Advisory issued as of 7 PM, 20 August 2018


Monthly Climate Assessment and Outlook (July-August 2018)

Issued: 06 August 2018

Monthly Rainfall Forecast
RAINFALL FORECAST  (September 2018 - February 2019) 
UPDATED: 29 August 2018 (next update September 26, 2018)

Regional Rainfall Forecast
Issued: 29 August 2018
Valid for: September 2018 - February 2019
Farm Weather Forecast and Advisories
ISSUED: 8 AM,  FRIDAY,  MAY 24, 2019
, 2019
FWFA:  N0. 19-144

Ten-Day Regional Agri-Weather Information
DEKAD NO. 15   MAY 21 - 31, 2019
The weather systems that will affect the whole country are the frontal system, easterlies, ridge of high pressure area, intertropical convergence zone (ITCZ) and low pressure area (LPA).

Seasonal Climate Outlook
Issued:  13 July 2018
FOR July - December 2018

Astronomical Diary
Issue for October 2018
The October Orionids meteor shower will be active from October 17-25, 2017.

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Carina G. Lao, Rafael P. Lao, Benjamin R. Ofina

This study attempts to improve the first paper of Lao (1989). The relationship between the variations of tropical cyclones in the Western North Pacific, in terms of cyclone days, and the rainfall and pressure of selected stations in Thailand and Hongkong, in addition to the previous data have been studied. The resulting relationships have been used to develop statistical methods for seasonal prediction.

The relationship between these cyclone days and the different variables are studied by the same methods used in the paper of Lao (1989).

Significant correlations are found between the Ubon Ratchathani (Thailand) rainfall and cyclone days. Years with relatively many tropical cyclones are preceded by high rainfall values in this area.

The regression equations which have been developed in this study are verified using one dependent data set and two independent data sets.

The results show that the most accurate prediction is one which predicts the number of cyclone days for the first half of the cyclone season (MAUG). This study suggests that the Western North Pacific tropical cyclone activity is predictable some months prior to the start of the cyclone season.

Flaviana D. Hilario

Two methods (maximum likelihood and parallelepiped) of classifying clouds types and terrestial surfaces at daytime using three channels of the Advanced Very High Resolution Radiometer (AVHRR) are presented. Using spectral information, five cloud types (low, cumulus, cirrus over land, high and combination of high and low), land, sea, and snow were identified. Both methods were able to classify land, sea, low, cirrus over land and high clouds fairly well. The use of the ratio of Channel 2 to Channel 1 helped in recognizing sunglint and snow as well as providing a very clear distinction between land and water surfaces which is not possible with the use of two-channel (visible and infrared) classification. However, difficulties were encountered by both techniques in identifying cumulus clouds and combination of high and low clouds. A visual comparison with the manual nephanalysis done by the Royal Meteorological Society showed that the maximum likehood was found to give better classified images than the parallelepiped but the latter is much faster. For better visual analysis, a majority filter was applied to the classified images. The smoothing technique resulted in less unclassified pixels for the parallelepiped classification and bigger cloud type areas for both methods.

Shirley V. Almazan

A numerical model for studying sea breeze rainfall is described. The model uses two-dimensional, time-dependent primitive equations and includes equations for predicting rain and cloud amounts explicitly. Integration of the model has been made to simulate the development of a sea breeze over flat terrain. The large scale prevailing conditions used in the simulation correspond to cases with no prevailing flow, with onshore prevailing flow and with offshore prevailing flow during the rainy season. Experiments on the effect of vertical stability on the characteristics of sea breeze rainfall were also made. The results show that the model is able to simulate the sea breeze circulation reasonably well. In addition, the results also show the development of rainfall in the early afternoon, its intensification with time and its subsequent weakening.