PAGASA Wind Signal Numbers Explained (Signal No. 1, Signal No. 3, Automatic Suspension)

Every storm season somebody asks me what a signal number means, and the honest answer is that it means less than people expect and it decides more than people expect. Both at once.

It is not a measure of how bad the storm is. It is a statement about the wind expected in one specific area, and it is the number the school and work closure rules are built on top of. Those two facts get mixed up constantly.

Photographs here are stock images for illustration and are not pictures of the events described.

The five levels and the wind behind them

PAGASA overhauled this in March 2022 and there have been five levels since. The thresholds are wind speeds expected in the area the signal covers.

Signal No. 1 is 39 to 61 kilometres per hour. Signal No. 2 is 62 to 88. Signal No. 3 is 89 to 117. Signal No. 4 is 118 to 184. Signal No. 5 is 185 and above, and it was added to the scale specifically so there was somewhere to put a super typhoon.

Notice how uneven the bands are. The step from 1 to 2 is about 25 kilometres per hour. The step from 3 to 4 is nearly 70, and the top band has no ceiling at all. So the difference between two adjacent numbers is not a constant amount of danger, and treating the scale as linear will mislead you badly at the top end.

The other thing to hold onto is that the number describes your area, not the storm. The same storm is a 4 for one province and a 1 for the province next door on the same afternoon. A person saying it is a signal 3 storm is saying something that does not really mean anything.

Signal No. 1 closes almost nothing

This surprises people who assume any signal means the day is cancelled.

Under the Department of Education order currently in force, Signal No. 1 does not automatically suspend classes for most students. Kindergarten is the exception. Grades 1 through 12 are expected to show up unless the local mayor separately declares otherwise.

Thirty-nine to sixty-one kilometres per hour is a windy day. It will take umbrellas apart and it will make a motorcycle ride unpleasant, and it is not going to hurt a building. The rule reflects that.

Where Signal No. 1 does matter is in what it implies about the next twelve hours. A signal is issued because forecasters expect that wind, which means the storm is close enough and organised enough to reach you. Signal No. 1 today is frequently Signal No. 2 tomorrow, and the useful reading of it is as a countdown rather than as a condition.

It also matters at sea long before it matters on land. Small boats stop moving at signal levels that have no visible effect on a city, which is why inter-island travel falls over first and why a traveller relying on ferries is affected several steps earlier than a traveller who is not.

Signal No. 3 is where the rule changes

At Signal No. 3 the discretion disappears.

Under DepEd Order No. 022, series of 2024, classes at all levels are suspended automatically once PAGASA raises Signal No. 3 or higher. Nobody has to declare anything. It happens because the signal was raised.

That threshold sits at 89 kilometres per hour, and it is a sensible place to draw the line. This is roughly where light structures start failing, where corrugated roofing becomes airborne, and where the walk to school stops being merely uncomfortable and starts being genuinely hazardous for a child.

It is also the point at which the decision stops depending on a person. Below it you are relying on a mayor's judgement, their read of local conditions, and the hour at which they get around to announcing. At and above it, the rule fires on its own.

For anyone trying to plan around a storm, Signal No. 3 is therefore the single most useful number on the scale. Not because the weather changes character there, but because the institutions do.

Automatic Suspension and who decides the rest

The full structure has three tiers, and it is worth knowing which one is operating.

Automatic suspension applies at Signal No. 3 and above and covers every level of schooling. At Signal No. 1 and 2, the local chief executive, meaning the mayor, decides. And for extreme heat or localised conditions that no signal covers, it falls to the school head or the schools division superintendent.

Almost every argument you will see online about closures is really an argument about the middle tier. That is where the same storm produces a suspension in one city and a normal school day in the next one, and where announcements land at ten at night or six in the morning depending on who is deciding.

Work suspension is a separate matter again and follows its own announcements, which is why people occasionally find that schools are closed and offices are not.

None of this is unique to the Philippines. Japan leaves it to individual boards of education, Hong Kong ties it rigidly to its own signal 8, and Korea leaves it to school principals. The Philippine version is unusual only in how explicitly the thresholds are written down.

What a signal number does not tell you

This is the part I would want somebody to tell me before a trip.

The signal is about wind. It says nothing about rain. A slow, sprawling, weak system can sit over a province for two days producing no signal above 1 and drown it anyway, and the flooding this month happened with no wind signal in force at all for most of it.

It says nothing about storm surge either, which is issued separately and is the hazard that historically kills the most people in coastal areas.

And it is not a forecast of intensity at the centre of the storm. It is a forecast of what reaches you. A violent typhoon passing two hundred kilometres offshore may never raise anything above Signal No. 2 over your town, and that number tells you nothing about the boats and the coastline in between.

So read the signal for what it is good for, which is wind and institutional decisions. Then go and read the rainfall warning separately, because that is a different product measuring a different thing, and in an average August it is the one that will actually change your day.

There is a reason the signal number is the thing everyone quotes. It is a single digit, it is on every broadcast, and it maps directly onto whether people have to go to work. That makes it useful shorthand and a poor summary, and it is worth keeping those two apart in your head.

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