THE PHILIPPINE PUBLIC STORM WARNING SIGNALS

PSWS # 1

METEOROLOGICAL CONDITIONS: A tropical cyclone will affect the locality. Winds of 30-60 kph may be expected in at least 36 hours or intermittent rains may be expected within 36 hours. (When the tropical cyclone develops very close to the locality a shorter lead time of the occurrence of the winds will be specified in the warning bulletin.)

IMPACT OF THE WINDS: Twigs and branches of small trees may be broken. Some banana plants may be tilted or downed. Some houses of very light materials (nipa and cogon) may be partially unroofed. Unless this warning signal is upgraded during the entire existence of the tropical cyclone, only very light or no damage at all may be sustained by the exposed communities. Rice crop, however, may suffer significant damage when it is in its flowering stage.

PRECAUTIONARY MEASURES: When the tropical cyclone is strong or is intensifying and is moving closer, this signal may be upgraded to the next higher level. The waves on coastal waters may gradually develop and become bigger and higher. The people are advised to listen to the latest severe weather bulletin issued by PAGASA every six hours. In the meantime, business may be carried out as usual except when flood occur. Disaster preparedness is activated to alert status.

PSWS # 2

METEOROLOGICAL CONDITIONS: A tropical cyclone will affect the the locality. Winds of greater than 60 kph and up to 100 kph may be expected in at least 24 hours.

IMPACT OF THE WINDS: Some coconut trees may be tilted with few others broken. Few big trees may be uprooted. Many banana plants may be downed. Rice and corn may be adversely affected. Large number of nipa and cogon houses may be partially or totally unroofed. Some old galvanized iron roofings may be peeled off. In general, the winds may bring light to moderate damage to the exposed communities.

PRECAUTIONARY MEASURES: The sea and coastal waters are dangerous to small seacrafts Special attention should be given to the latest position, the direction and speed of movement and the intensity of the storm as it may intensify and move towards the locality. The general public especially people travelling by sea and air are cautioned to avoid unnecessary risks. Outdoor activities of children should be postponed. Secure properties before the signal is upgraded. Disaster preparedness agencies / organizations are in action to alert their communities. PSWS # 3 METEOROLOGICAL CONDITIONS: A tropical cyclone will affect the locality. Winds of greater than 100 kph up to 185 kph may be expected in at least 18 hours. IMPACT OF THE WINDS: Many coconut trees may be broken or destroyed. Almost all banana plants may be downed and a large number of trees may be uprooted. Rice and corn crops may suffer heavy losses. Majority of all nipa and cogon houses may be unroofed or destroyed and there may be considerable damage to structures of light to medium construction. There may be widespread disruption of electrical power and communication services. In general, moderate to heavy damage may be experienced, particularly in the agricultural and industrial sectors. PRECAUTIONARY MEASURES: The disturbance is dangerous to the communities threatened/affected. The sea and coastal waters will be very dangerous to all seacrafts. Travel is very risky especially by sea and air. People are advised to seek shelter in strong buildings, evacuate low-lying areas and to stay away from the coasts and river banks. Watch out for the passage of the "eye" of the typhoon indicated by a sudden occurrence of fair weather immediately after very bad weather with very strong winds coming gnerally from the north. When the "eye" of the typhoon hit the community do not venture away from the safe shelter because after one to two hours the worst weather will resume with the very strong winds coming from the south. Classes in all levels should be suspended and children should stay in the safety of strong buildings. Disaster preparedness and response agencies/organizations are in action with appropriate response to actual emergency. PSWS # 4

METEOROLOGICAL CONDITIONS: A very intense typhoon will affect the locality. Very strong winds of more than 185 kph may be expected in at least 12 hours.

IMPACT OF THE WINDS: Coconut plantation may suffer extensive damage. Many large trees may be uprooted. Rice and corn plantation may suffer severe losses. Most residential and institutional buildings of mixed construction may be severely damaged. Electrical power distribution and communication services may be severely disrupted. In the overall, damage to affected communities can be very heavy.

PRECAUTIONARY MEASURES: The situation is potentially very destructive to the community. All travels and outdoor activities should be cancelled. Evacuation to safer shelters should have been completed since it may be too late under this situation. With PSWS #4, the locality is very likely to be hit directly by the eye of the typhoon. As the eye of the typhoon approaches, the weather will continuously worsen with the winds increasing to its strongest coming generally from the north. Then a sudden improvement of the weather with light winds (a lull) will be experienced. This means that the eye of the typhoon is over the locality. This improved weather may last for one to two hours depending on the diameter of the eye and the speed of movement. As the eye moves out of the locality, the worst weather experienced before the lull will suddenly commence. This time the very strong winds will come generally from the south. The disaster coordinating councils concerned and other disaster response organizations are now fully responding to emergencies and in full readiness to immediately respond to possible calamity.

I have learned that storm signal number 1 is the first storm/typhoon warning said in the TV news broadcasts when the local weather bureau (PAGASA) detects a storm. Normal classes usually are in service still.I have learned that storm signal no. 2can affect the locality win a wind speed of 60kph to 100 kph in atleast 24 hrs. The storm signal no.3 affects the locality with the speed of 100kph to 185kph in atleast 18hrs.The storm signal no.4 can affect the locality with 185 kph and above in atleast 12 hrs. I want to know more about the effects this storm signal to the community. I would like to research on how it is formed. I appreciate the fact that winds of 30-60 kph may be expected in at least 36 hours or intermittent rains may be expected within 36 hours. I can apply my learning and insights on sharing it to my friends.

The Fujiwhara effect or Fujiwara interaction, named after Sakuhei Fujiwhara, is a type of interaction between two nearby cyclonic vortices, causing them to appear to "orbit" each other.

When the cyclones approach each other, their centers will begin orbiting cyclonically about a point between the two systems due to their cyclonic wind circulations. The two vortices will be attracted to each other, and eventually spiral into the center point and merge. When the two vortices are of unequal size, the larger vortex will tend to dominate the interaction, and the smaller vortex will orbit around it.

The effect is often mentioned in relation to the motion of tropical cyclones, although the final merging of the two storms is uncommon. The effect becomes pronounced in these storms when they approach within about 1,500 km (900 mi) of each other and are at tropical storm strength or stronger.

The effect is named after Sakuhei Fujiwhara, the Japanese meteorologist who initially described it in a 1921 paper about the motion of vortices in water.

1. I learned that named after Sakuhei Fujiwhara, is a type of interaction between two nearby cyclonicvortices, causing them to appear to “orbit” each other.
2. I want to know more abouton how it affects the weather system. 

3. I would like to research on how it affects the weather in the Philippines.

4. I can apply my learning and insights on having a broader knowledge to further understand the Philippine weather.

Tropical Cyclones

I learned that Tropical Cyclone is a low pressure systems that form over warm tropical waters and have gale force winds (sustained winds of 63 km/h or greater and gusts in excess of 90 km/h) near the centre. Technically they are defined as a non-frontal low pressure system of synoptic scale developing over warm waters having organised convection and a maximum mean wind speed of 34 knots or greater extending more than half-way around near the centre and persisting for at least six hours.

The gale force winds can extend hundreds of kilometres from the cyclone centre. If the sustained winds around the centre reach 118 km/h (gusts in excess 165 km/h). then the system is called a severe tropical cyclone. These are referred to as hurricanes or typhoons in other countries.

I want to know more about on how this phenomenon can affect, impact, put each and everyone in danger so that we can do ways on how to protect ourselves in case the emergency comes.

I would like to research on the different ways to predict the tail end of a cold front and on some proper ways of what we can do to prepare for the phenomenon.

I appreciate the fact that it doesn’t affect large areas. But it doesn’t also mean that we can relax about it. We should be aware with it is possible effects.

I can apply my learning and insights in understanding the weather phenomenon, be able to perform it on our daily life.And most important is, I can share my learning to my other fellowmen and widen their knowledge