Gale Warning
Issued at: 5:00 PM TODAY , 01 August 2017
Gale Warning # 10 (Final)
For: STRONG TO GALE FORCE SOUTHWESTERLY SURFACE WINDFLOW

Gale Warning in PDF file




Weather Advisory
As of today, there is no weather Advisory issued



Dams Water Level Update
As of 6 AM, 17 August 2017

General Flood Advisories - Regional
Issued as of 7PM 16 August 2017


Daily Basin Hydrological Forecast
Issued 16 August 2017




Monthly Climate Assessment and Outlook

Issued: 04 August 2017

Monthly Rainfall Forecast
RAINFALL FORECAST  (July - December 2017) 
UPDATED: 04 July 2017 (next update August 2017)


Regional Rainfall Forecast
Issued: 05 July 2017
Valid for: July - December 2017
Farm Weather Forecast and Advisories
ISSUED              : 8AM, WEDNESDAY, AUGUST 16, 2017
VALID UNTIL      :  8AM, THURSDAY, AUGUST 17, 2017
FWFA:  N0. 17-229


Ten-Day Regional Agri-Weather Information
DEKAD NO. 23 AUGUST 11-20, 2017

PHILIPPINE AGRI-WEATHER FORECAST
The weather systems that will affect the whole country are southwest monsoon and ridge of high pressure area (HPA).
Seasonal Climate Outlook
Issued:  06 July 2017
FOR July - December 2017
PDF 




Astronomical Diary
Issue for August 2017
A partial lunar eclipse will occur on 7-8 August 2017...




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A. Cloud Description

 

SKY CONDITIONDEFINITION/DESCRIPTION

Clear or Sunny Skies

  • State of the sky when it is cloudless, totally clear or with a few small light clouds visible.
  • Has a total cloud cover of less than one okta.

Partly Cloudy

  • State of the sky is within 2-5 oktas total cloud cover or has between 30% to 70% cover of the celestial dome.

Partly Cloudy to at Times Cloudy

  • Mostly partly cloudy but there are times when more than 70% of the celestial dome is covered with clouds.

Mostly or Mainly Cloudy

  • The sky is mostly covered with clouds but with possible brief periods of sunshine.
  • The total cloud cover is between 6 to 8 oktas.

Cloudy

  • The sky is covered with clouds between 6 to 8 oktas or has more than 70% cloud cover.
  • Predominantly more clouds than clear sky.
  • For a longer period during the day, the sun is obscured by clouds.

Overcast

  • The sky is totally or completely covered with thick and opaque clouds, 8 oktas or around 100% cloud cover.

A. Cloud Description

 

SKY CONDITIONDEFINITION/DESCRIPTION

Clear or Sunny Skies

  • State of the sky when it is cloudless, totally clear or with a few small light clouds visible.
  • Has a total cloud cover of less than one okta.

Partly Cloudy

  • State of the sky is within 2-5 oktas total cloud cover or has between 30% to 70% cover of the celestial dome.

Partly Cloudy to at Times Cloudy

  • Mostly partly cloudy but there are times when more than 70% of the celestial dome is covered with clouds.

Mostly or Mainly Cloudy

  • The sky is mostly covered with clouds but with possible brief periods of sunshine.
  • The total cloud cover is between 6 to 8 oktas.

Cloudy

  • The sky is covered with clouds between 6 to 8 oktas or has more than 70% cloud cover.
  • Predominantly more clouds than clear sky.
  • For a longer period during the day, the sun is obscured by clouds.

Overcast

  • The sky is totally or completely covered with thick and opaque clouds, 8 oktas or around 100% cloud cover.

Precipitation (Rain & Rainshowers) Description

B. Precipitation (Rain & Rainshowers) Description

1. Rains

  • Overcast sky with continuous or steady precipitation that may last several hours.
  • Has a water droplets of 0.5 mm or greater in size but if widely scattered the drops may be smaller.
  • Associated with meso-scale (synoptic) system or macro-scale (large scale) system like TC's, Easterly Waves, Monsoons, Fronts and ITCZ.

 

RAIN CLASSIFICATIONDEFINITION/DESCRIPTION

Very Light Rains

  • Scattered drops that do not completely wet an exposed surface regardless of duration.

Light Rains

  • The rate of fall is from trace to 2.5 mm per hour.
  • Individual drops easily identified and puddles(small muddy pools) form slowly.
  • Small streams may flow in gutters.

Moderate Rains

  • The rate of fall is between 2.5 mm to 7.5 mm per hour.
  • Puddles rapidly forming and down pipes flowing freely.

Heavy Rains

  • The rate of fall is greater than 7.5 mm per hour.
  • The sky is overcast, there is a continuous precipitation.
  • Falls in sheets, misty spray over hard surfaces.
  • May cause roaring noise on roofs.

Monsoon Rains

Other Descriptions:

  • Heavy and continuous precipitation attributed to either the Southwest or Northeast Monsoon.

Occasional Rains

  • Not frequent but is recurrent precipitation.

Widespread Rains

  • Precipitation occuring extensively throughout an area.

Frequent rains

  • Precipitation occuring regularly and often throughout the time duration.

Intermittent Rains

  • Precipitation which ceases at times and re-occur again.

 

2. Rainshowers

  • Precipitation of short duration but usually of greater intensity from convective clouds(primarily cumulus or cumulonimbus)
  • Characterized by sudden start and sudden end of precipitation, rapid change in intensity.

 

RAINSHOWERSDEFINITION/DESCRIPTION

Scattered Rainshowers

  • The rain-bearing clouds is distributed spatially resulting to rainshowers occuring to the bigger part of the forecasted area.

Isolated Rainshowers

  • The rain-bearing clouds is small and isolated resulting to rainshowers occuring only to a small part of the forecasted area.

Occasional Rainshowers

  • There is a large amount of convective clouds and precipitation occur in most parts of the forecasted area occasionally, and varying in rainfall amount.

Squally Rainshowers

  • Showers accompanied by brief but sudden strong or gale force winds.




C. Wind Description(Based from the Beaufort Wind Scale and the Saffir-Simpson Scale)

 

WIND DESCRIPTION

UNITS in KPH

UNITS in KNOTS

DESCRIPTION AS OBSERVED

Light Winds

19 or less

10 or less

  • Wind felt on face.
  • Ordinary wind vanes moved by wind.
  • Leaves rustle.

Moderate Winds

20-29

11-16

  • Wind raises dust and loose paper.
  • Small branches are moved.

Moderate to Occasionally Strong

   
  • Moderate winds mostly persist but there are instances during the forecast period that it reaches strong wind force.

 Fresh Winds*

30-39

17-21

  • Small trees in leaf begin to sway.
  • Crested wavelets appear on inland waters.
 Strong Winds 40-50 22-27
  • Large branches in motion.
  • Whistling heard in telephone wires.
  • Umbrellas used with difficulty.

Gale:

1 Near Gale*

2 Gale
3 Strong Gale*

 

51-62

63-75
76-87

 

28-33

34-40
41-47

 

  • Whole trees in motion.
  • Inconvenience felt when walking against wind.
  • Twigs break off road.
  • Cars veer on road.
  • Larger branches break off.
  • Slight structural damade occurs-roofing dislodged.

Stormy:

1 Storm

2 Violent Storm*

3 Typhoon*

 

88-102

103-117

118 or more

 

48-55

53-63

64 or more

 

  • Trees uprooted.
  • Considerable structural damage.
  • Widespread damage.
  • Widespread damage.

  • *Terms that are not normally used by meteorological centers in forecasts formulation and communication
  • Gust - any sudden brief increase of wind speed usually less than 20 seconds followed by a lull or slackening in wind speed




D. Sea Condition as affected by Wind Force (Based from the Beaufort Wind Scale)

 

WIND FORCEUNITS in (MPS)UNITS in (KTS)WAVE HT.(METERS)SEA CONDITION
 Calm 0-1.5 0-3.0 0.1
  • Ripples with the appearance of scales are formed but without foam crests.
 Smooth 1.5-4.0
 
3.0-8.0
 
0.1-0.5
 
  • Small wavelets, still short but more pronounced.

 

  • Crest have glassy appearance and do not break.
 Slight 4.0-8.0
 
8.0-16.0
 
0.5-1.25
 
  • Small waves, becoming longer.
  • Fairly frequent white horses.
 Moderate 8.0-11.0
 
16.0-22.0
 
1.25-2.5
 
  • Moderate waves taking a more pronounced long form.
  • Many white horses are formed-a change of some spray.
 Rough 11.0-16.0 22.0-32.0 2.5-4.0
  • Large waves begin to form.
  • Sea heaps up and white foam from breaking waves begin to be blown in streaks along the direction of wind.
 Very Rough 16.0-20.0

 
32.0-40.0

 
4.0-6.0

 
  • Moderately high waves of greater length.
  • Edges of crest begin to break into spindrift.
  • Foam is blown in well-mark streaks along the direction of the wind.
 High 20.0-26.0

 
40.0-52.0

 
6.0-9.0

 
  • High to very high waves with long overhanging crests.
  • The surface of the sea takes on white appearance.
  • The thumbling of the sea becomes heavy with visibility affected.
 Very High 26.0-34.0


 
52.0-68.0


 
9.0-14.0


 
  • Exeptionally high waves.
  • Small and medium size ships occasionally lost from view behind waves.
  • The sea is completely covered with long white patches of foam.
  • The edges of wave crest are blown into froth.
 Phenomenal >34.0

 
>68.0

 
>14.0

 
  • The air is completely filled with foam and spray.
  • Sea completely white with driving spray.
  • Visibility very seriously affected.

 

MDSI v2

PUBLIC WARNING 


It has come to the attention of the Office of the Administrator of PAGASA that a certain person has been using the name of Dr. Vicente B. Malano to solicit money from the contractors of PAGASA.

Dr. Malano wishes to inform the public that he has not authorized anyone to solicit money on his behalf and to warn everyone against dealing with unscrupulous activities of certain individuals.



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