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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Flaviana D. L. Hilario

Point estimates of hourly, 3-hr. 6-hr, 12-hr and 24-hr rainfall from tropical cyclones were computed using 3-hr interval of infrared and visible images from the Geostationary Meteorological Satellite (GMS) of Japan. Multiple regression models involving   IR, VIS and combination of the two parameters were developed to estimate short duration rainfall Independent data were used to validate the models.

For very short duration rainfall estimation (hourly and 3-hr), the correlation between the observed and the estimated rainfall from IR only models is very low. However, it was observed that high rainfall values are always associated with high IR brightness value but high IR brightness value is not always associated with high rainfall values. On the other hand, the visible parameters were found to be highly correlated with very short duration rainfall. This could be attributed to the presence of   cirrus   anvil which   is more   sensitive   to the   infrared than   the   visible measurements.

The total time period of the rainfall estimation appears to be an important factor in the accuracy of the calculations particularly with models involving infrared parameters only.  The scatter of hourly and 3-hr rainfall estimates are relatively large, however, the scatter decreases as estimates are accumulated over longer period of time.  For models with visible parameters, the scatter also decreases as the period of accumulation increases.
In general, the estimated rainfall for the periods hourly, 3-hr, 6-hr, 12-hr and 24-hr showed overestimation for lower rainfall values and underestimation for higher rainfall values.  The results also showed that as the period of accumulation of rainfall increased, the correlation between the observed and the estimated rainfall also increased.

Validation of the five models (with IR parameters only) using independent data sets (T.C. Akang) yielded slightly lower correlation coefficients for 3-hr to 12- hr rainfall estimation.  The 24-hr estimated rainfall has much lower correlation coefficient which can attribute to the limited number of samples used in the model development. Models with visible brightness as parameter adequately estimated 3-hr, 6-hr and 9-hr rainfall of T.C. Akang. Validation of the 3rd order polynomial of IR for 6-hr and 12-hr rainfall showed relatively poor performance of the model.  The observed rainfall from the synoptic stations are much higher than the rainfall used in model development which could account for the low skill of the model.