Gale Warning
Issued at: ,
Gale Warning #

Gale Warning 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.

   PAGASA webmail  Learning Tools  Bidding 

  Training Activities  Vacancy  Research-and-Development

  Engineering  faqupdate  Publications 

Rolu P. Encarnacion

A numerical model of the cold surge is developed to simulate cloudiness and rainfall over a warm ocean surface and a land mass with prominent topographic features. The model atmosphere consists of 3 layers: a) surface layer b) mixed layer and c) stable layer. The set of primitive equations is averaged in the mixed layer to yield prediction equations for the horizontal components of the wind, potential temperature and mixing ratio in the layer, and the height of the base of the overlying stable layer. Parameterizations of the interactions between the well-mixed convective layer with both the underlying and overlying layers are employed so that time dependent calculations could be limited to the well-mixed layer.

The model is used to study the dependence of cloudiness and rainfall associated with a cold surge on the prevailing synoptic conditions. A radiosonde observation representing inland conditions is utilized to define the initial state of the atmosphere for a control run. The control run and other numerical integrations (experiments) were used to analyze the cloudiness and rainfall patterns. Two groups of experiments were performed in this study: a) cold surge flow from land mass to warmer ocean surface and b) cold surge flow from the ocean to a warmer land mass with topography.

The results show that the model is capable of simulating the behavior of the atmosphere during cold surge episodes. The predicted variables are found to be reasonable and physically realistic.