The document discusses humidity, rainfall, and climate in the Philippines. It provides the following key points: 1) Relative humidity is high in the Philippines due to evaporation from surrounding seas, rich vegetation, and seasonal winds and rains. Humidity remains high throughout the year across the islands. 2) Rainfall varies regionally due to topography and wind patterns. Northeast monsoon rains from November to February bring heavier rainfall to eastern parts of the country. 3) Four main climate types are recognized based on rainfall patterns - ranging from distinct wet/dry seasons to more uniformly distributed rainfall throughout the year.

1. CLIMATE

2. HUMIDITY
Refers to the moisture of the atmosphere.
When the temperature is warm and the place is near of the
bodies of water, more moisture is evaporated to form clouds
RELATIVE HUMIDITY- is the ratio of the actual moisture
content of the atmosphere to that which it can hold to be
saturated at the same temperature.
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3. Rev. Father Coronas
Relative humidity in the Philippines is mainly due
to extraordinary evaporation from the seas that
surround them on all sides, to the richness of
vegetation, to different prevailing winds in
different seasons of the year and to the abundant
rains so proper to a tropical country. The first two
general causes of great humidity are generally
observe in all islands throughout the year. The
first two general causes of the great humidity are
generally observed in all islands throughout the
year. The other two influence in different degrees
the humidity of the different regions of
archipelago. In winter, when the rains are so
abundant in the eastern part of the Philippines
owing to the prevailing northeasterly winds,
humidity is greater than in the western part

4. RAINFALL
Rainfall is more important in the Philippines as a climatic element
than temperature .
Rainfall distribution throughout the country varies from one region to
another due to topography and the wind systems .
During the cool months, the rains in the Philippines are mainly due to
north-easterly air currents which come directly from the pacific ocean
causing rainfall over the eastern part of the archipelago. These are the
so-called northeast-monsoon rains.
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5. AVERAGE RAINFALL IN THE PHILIPPINES BY KEY STATIONS
FROM 1965 TO1970. STATIONS (IN MILLIMETERS)
MONTHS LAOAG MANILA LEGASPI PUERTO
PRINCESA
CEBU DAVAO
JANUARY 1.6 9.4 351.8 41.8 122.9 147.2
FEBRUARY 0 5.5 142.9 11.2 49.2 94.9
MARCH 1.0 4.6 182.9 32.9 33.8 86.2
APRIL 23.5 17.3 125.2 33.9 28.8 114.8
MAY 169.7 147.3 106.4 131.3 77.7 234.0
JUNE 439.1 245.0 176.8 149.5 192.7 135.4
JULY 380.4 346.7 283.4 199.0 171.9 150.0
AUGUST 538.5 389.4 288.8 212.1 165.6 176.0
SEPTEMBER 528.5 509.6 283.4 197.0 123.0 180.6
OCTOBER 78.3 158.8 301.3 197.0 123.0 180.6
NOVEMBER 63.3 95.5 494.1 270.0 170.0 142.0
DECEMBER 5.7 35.5 488.1 80.1 80.0 99.6
TOTAL 2,229.6 1,964.6 3,225.2 1,646.8 1,376.1 1,738.7

6. BASED ON THE DISTRIBUTION OF RAINFALL, FOUR
CLIMATIC TYPES ARE RECOGNIZED. THESE CLIMATIC
TYPES ARE DESCRIBED AS FOLLOWS:
TYPE 1- two pronounced wet and dry season; wet during
months of June to November and dry from December to May.
This type of climate is found in the western part of Luzon,
Mindoro, Palawan, Panay and Negros. The controlling factor is
topography. These regions are shield from the northeast
monsoon ranges, but are open to the southwest monsoon and
cyclonic storms.

7. TYPE 2- No dry season with a very pronounced maximum rain period in
December, January and February. Catanduanes, Sorsogon, Eastern part of
Albay, Camarines Norte, Camarines Sur, Eastern Quezon Samar, Leyte and
Eastern Mindanao have this type. These regions are along or very near in the
eastern coast and are not sheltered either from the northeasterly and trade
winds or from the cyclonic storms.
TYPE 3- This is an intermediate type with no pronounced maximum rain period
and a short dry season lasting from one to three months only. Areas under this
type are the western parts of the Cagayan Valley, the eastern part of the
Mountain Region, Southern Quezon, Masbate, Romblon, Northeastern Panay,
Eastern Negros, central and southern Cebu, eastern Palawan and Northern
Mindanao. These localities are only partly sheltered from the northeasterly and
trade winds and are open to the southwest monsoon or at least to frequent
cyclonic storms.

8. TYPE 4- Uniformly distributed rainfall. The regions affected by
this type are the Batanes, Northeastern Luzon, Southwestern
part of Camarines Norte, Western part of Camarines Sur and
Albay, Bondoc, Peninsula, Eastern Mindoro, Marinduque,
Western Leyte, Northern Cebu, Bohol and most of Central,
Eastern and Southern Mindanao. These regions are so
situated that they are open to the northeasterly and trade
winds as well as the southwest monsoon and the cyclonic
storms.

9. PRESSURE AND WINDS
Compared to temperature and rainfall, Pressure and winds are
relatively insignificant as elements of weather and climate. Although
winds of high velocity are dangerous to crops and buildings, the sum
total of the direct effects of the winds on man is less significant.
The higher the difference the greater is the velocity of the wind.
Pressure and winds exert a profound effect on the temperature and
precipitation. A minor change in pressure may cause a change in the
velocity and direction of the wind. A change in the movement of the
wind may produce changes in temperature which may in turn affect
precipitation.
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10. •There are three important air movements in the Philippines:
(a) trade winds
- originate in the high pressure area of the eastern north pacific
ocean.
(b) southwest monsoon
- is the deflected southwest trades of the southern hemisphere.
(c) northeast monsoon
- which is often times called northern, blows during the month of
November to February. This is the period when it is winter in the
northern hemisphere.

11. •Trade winds

12. • Southwest Moonsoon

13. •Northeast Moonsoon

14. Thank
you :)