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 Tropical Cyclone Alert


What to do:

The people are advised to monitor for the latest weather bulletin issued by PAGASA every 12 hours. In the meantime, business may be carried out as usual.



 Tropical Cyclone Warning



Public Storm Warning Signal # 1
PSS1

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.)
WHAT TO DO:
  • Inspect your house if necessary repair/fixing is needed.
  • Clean up drainage system.
  • Harvest crops tha can be yielded.
  • Monitor the latest Severe Weather Bulletin issued By PAGASA every six hours and hourly updates.
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.
Public Storm Warning Signal # 2
PSS2
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.
WHAT TO DO:
  • Prepare flashlights, batteries , matches, kerosene lamps, or candles and charcoal in anticipation of power failure, first aid kit and store ready to eat foods.
  • Keep your cell phones fully charged.
  • Elevate household things in case of flooding.
  • For fishing folks, secure fishing boats in safe area.
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.
Public Storm Warning Signal # 3
PSS3
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.
WHAT TO DO:
  • If the house is not strong enough to withstand the battering of strong winds go to designated evacuation center aor seek shelter in stronger houses.
  • Stay in safe houses until after the disturbances has left the area.
  • Evacuate from low-lying area and reiverbanks and stay away from coastal areas for possible flooding and strom surge.
  • All travel and outdoor activities should be cancelled.
  • Watch out for the passage of the "Eye Wall and the "Eye" of the typhoon.
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.
Public Storm Warning Signal # 4
PSS4
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.
WHAT TO DO:
  • If the house is not strong enough to withstand the battering of strong winds go to designated evacuation center aor seek shelter in stronger houses.
  • Stay in safe houses until after the disturbances has left the area.
  • Evacuate from low-lying area and reiverbanks and stay away from coastal areas for possible flooding and strom surge.
  • All travel and outdoor activities should be cancelled.
  • Watch out for the passage of the "Eye Wall and the "Eye" of the typhoon.
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.
Preparation of Flood Forecast

The preparation, issuance and dissemination of an adequate and timely warning is the ultimate purpose of flood forecasting. Timeliness is an essential requirement for a flood warning. A sufficient lead time enables the ultimate user to take the necessary precautionary countermeasures.
 

         The hydrological and meteorological conditions in a river basin and the consequent state of its river system is never constant. The behavior of the river itself is the resultant of the interaction of all hydrological processes and conditions in the river basin.
 

         A flooding situation is not a daily occurrence. However, flood forecasting operations must, of necessity, be a continuous activity. It is carried out from day to day even when the possibility of a flood is highly improbable. This mode of operation enables flood forecasters to pinpoint the beginning of a potential flood-generating situation.
 

        Like storm bulletins which are issued only during the presence of tropical cyclones, flood forecast and warning bulletins are prepared only when a potential flooding situation is definitely present. They are issued regularly at specified hours of the day for the duration of the flooding period until the flood recedes or when all hazards and dangers associated with the phenomenon are no longer present.
 

       The prevailing hydrometeorological situation in a given river basin defines the operational environment under which flood forecasting and warning operations are carried out. Conveniently categorized into
 

these operational situations are dependent for their implementation on the behavior and state of the river with respect to a set of criteria known as flood assessment levels.

In practice1 flood bulletins are issued as soon as the development of a flooding situation exists. The initial bulletin serves merely to alert the people in the threatened basin to the possibility of a flood. It is never intended to categorically state that there will be flooding but only of the possibility. The initial bulletin is issued as soon as the operational situation passes from the alert to the warning phase. The transition from one operatiohal status to another is based on pre-determined criteria.

Thus, flood forecasting operation needs to be a continuing activity to determine the point in time when the operational situation passes from one phase to another. A flood forecasting operation consists of the following:


Monitoring:

This requires the collection, at regular interval, of the real-time data on rainfall, water level and other information that affect the hydrological condition of the river basin and the state of the river system. This provides a broad picture of the current situation in a river basin.

Analysis:


The data are analysed and related to other available information such as storm data from radar and satellite observation. The general objective here is to deduce the probable development in the hydrological situation in the river basin in the near future. This part of the operation involves a variety of hydrological analyses as well as the use of flood forecasting models to provide an objective estimate of the fore­cast situation.


Preparation of the forecast and warning:

Flood forecasts are completed in time for release at regular preset time of issuance. Dissemination is made through dissemi­nating agencies such as the OCD1 DSWD, NDCC, and thru the mass media, particularly radio and television.

There are three categories of flood information intended for the general public. All are issued under the general title of "Flood Bulletin". A distinct series of bulletins is issued for each threatened river basin where the forecasting and warning service is already extended and operational. As already stated, bulletins are issued only when conditions,

i.e., there is a potential flooding situation, so warrant their issuance.

When required, flood bulletins are prepared twice daily. They are completed and readied for issuance and dissemination at 5 a.rn. and 5 p.rn., respectively, when it is deemed early enough to provide vital information for concerned users to take necessary countermeasures before they leave for work in the morning or before they retire at night.

A series of bulletins for a given affected river basin is ideally initiated by a Flood Outlook. As the category implies, the bulletin merely states the present hydrological situation and alerts the people in a basin to the possibility of a deteriorating condition, e.g., a gradual and continuous rise in the water level.

Subsequent bulletins could be of any one of the three categories. Normally, for a given affected basin, one bulletin is followed by another of the same in the next higher category depending on the development in the hydrological condition and the forecast situation. Hence, an Outlook is followed by another Outlook or by a Flood Advisory; or by a Flood Warning.

When the situation had clearly reached its worst such that, at most the condition or, at best, improvement can be expected, subsequent bulletins are of the same or by a next lower category than the proceeding.

Upon receipt of the coded messages, they are decoded and each set of observations is plotted in symbols or numbers on weather charts over the respective areas or regions.  Observations made over land and sea are plotted on the surface or mean sea level charts which are prepared four times a day.  Radiosonde, theodolite, aircraft and satellite wind observations are plotted on upper level charts which are prepared twice daily.


Flood bulletins are specifically directed to the public. They are intended to apprise the people in the threatened area of the present situation and of the expected development. It suggests the appropriate actions the community may have to take to prevent or mitigate the disastrous effects of a flood.

  As in any kind of disaster, the best countermeasures for flood damage prevention and mitigation are those which are community efforts.

  Floods cannot be prevented. To a large extent, however, they can be controlled effectively. By this is meant keeping the river from overflowing. There are a number of ways of accomplishing this before and during a flood:
 When overbanking can no longer be avoided, flood control can take the form of directing floodwaters where it can do the least damage.
 Individually and collectively, people in a flood-stricken area must take precautionary measures to ensure personnel safety and health:

  1. People, particularly children, should avoid wading in floodwaters.
  2. Where houses are expected to be flooded, people should move to higher places.
  3. Electrically operated appliances should be transferred to upper storeys of buildings.
  4. When electrical fines and outlets will be submerged in floodwater, power should be switched off.
Flood damage mitigation and protection is a concern not only during the disaster. It should be practiced before, during and after the occurrence of a flood.   

Flood Safety Rules


    


BEFORE THE FLOOD:

WHEN WARNED OF FLOOD: DURING THE FLOOD: AFTER THE FLOOD: Flood are aggravated by factors resulting from the carelessness and indifference of people usually before floods occur.

THINGS ONE CAN DO TO MITIGATE FLOODS: