Yellow, orange, red. Signal No. 1 to 5. A heat index that reads "danger." PAGASA throws a wall of colors and numbers at communities across Luzon, the Visayas, and Mindanao every single day — and behind every one sits a single practical question: do you stay put, or do you move? Here is what each warning actually means, and the exact moment it demands action.
Rainfall warnings: yellow, orange, red
PAGASA's rainfall advisory uses three colors based on how hard the rain is falling and what flooding it is likely to cause:
- Yellow — heavy rain, with 7.5 to 15 millimeters of rain within one hour and expected to continue. Flooding is possible in low-lying areas. Be aware and monitor updates.
- Orange — intense rain, 15 to 30 millimeters within one hour. Flooding is a definite threat. Be prepared to respond — pre-emptive evacuation may be ordered.
- Red — torrential rain, more than 30 millimeters within one hour, or rain that has continued for three hours and already exceeds 65 millimeters. This is an emergency; serious and widespread flooding is expected. Act now; evacuate if told to, or if water is rising.
The key mindset: the color is not about how scary the sky looks — it is about expected impact over the next few hours. Orange means decisions, not observation.
Tropical Cyclone Wind Signals (Signal No. 1 to 5)
When a tropical cyclone approaches, PAGASA raises a wind signal for each area, from 1 (lowest) to 5 (highest). Two things change as the number rises: the wind speed expected, and how soon it will arrive. Under the system in force since March 23, 2022:
- Signal No. 1 — winds of 39 to 61 km/h expected within 36 hours. Minimal to minor threat.
- Signal No. 2 — 62 to 88 km/h. Minor to moderate threat; classes are often suspended.
- Signal No. 3 — 89 to 117 km/h. Moderate to significant threat; light structures at risk.
- Signal No. 4 — 118 to 184 km/h. Severe; widespread damage likely.
- Signal No. 5 — 185 km/h or higher. Reserved for the most violent storms, of super typhoon strength; catastrophic damage.
A common confusion worth clearing up: the wind signal measures wind, while the colored advisories measure rain. A storm can be far away (low signal) yet still dump red-level rain — which is why deadly floods sometimes happen under "only Signal No. 1."
Gale warnings: the alert for those who go to sea
Not every dangerous-weather alert involves a typhoon. A gale warning is raised when strong to gale-force winds are prevailing or expected over coastal waters — generally the sea areas within 30 nautical miles of the coast — even when no tropical cyclone is present. During the cool months, the most common trigger is the amihan, the northeast monsoon.
For fisherfolk and island commuters, this is often the warning that matters most. Under a gale warning, sea travel is risky for all small seacraft, including motor bancas of any type or tonnage, and mariners are advised to stay in port or seek safe harbor. Wave heights can climb to several meters. In a country where thousands cross open water every day, a gale warning quietly prevents more deaths than any single typhoon signal.
Thunderstorm advisories: the 30-minute alert
The fastest-moving warning PAGASA issues is the thunderstorm advisory. It signals that moderate to heavy rainshowers with lightning and strong winds are expected within the next 30 minutes to one hour over a specific area. Because thunderstorms build and strike quickly, these advisories are short-fuse — by the time one is issued, you have minutes, not hours. They are also a leading cause of sudden flash floods and lightning deaths, so the right response is immediate: get indoors, and stay away from open fields, tall isolated trees, and water.
Heat index: when "feels like" is the danger
The heat index combines temperature and humidity into what the weather actually feels like on your skin. PAGASA groups it into bands as the "feels-like" figure climbs:
- Below 27°C — not hazardous.
- Caution (27 to 32°C) — fatigue possible with prolonged exposure.
- Extreme Caution (33 to 41°C) — heat cramps and heat exhaustion possible.
- Danger (42 to 51°C) — heat cramps and heat exhaustion likely; heat stroke possible with continued exposure.
- Extreme Danger (52°C and above) — heat stroke is imminent.
Once readings hit the Danger range, outdoor work and class schedules are often adjusted.
Watch vs. warning vs. advisory
An advisory or watch says conditions are favorable — stay alert. A warning says it is happening or imminent — act.
How a storm day actually escalates
Put together, the system tells a story as conditions worsen. A distant tropical cyclone might first bring a Signal No. 1 and a yellow rainfall advisory — be aware. As it nears, the signal climbs to No. 2 or 3 and the rain advisory jumps to orange, the point at which school, work, and travel decisions should already be made. If the rain turns torrential, a red advisory follows, often paired with thunderstorm advisories for the heaviest cells, while coastal areas sit under a gale warning. The lesson: do not wait for the highest number. The orange-and-Signal-3 stage is when action is still easy; the red stage is when it is already dangerous.
How to spot weather misinformation
Every storm season brings a flood of fake forecasts — screenshots claiming "Signal No. 5 tomorrow," doctored satellite images, and recycled photos from old typhoons. Three quick checks defeat almost all of them: confirm the source is PAGASA's official page or a verified account; check the date and time stamp on the advisory; and remember that PAGASA does not predict specific signal numbers days ahead with certainty. If a post cannot survive those three checks, do not share it. Passing on a false alarm can be as harmful as ignoring a real one.
What to actually do
- Follow PAGASA's official channels for warnings; treat unverified "Signal No. 5 tomorrow!" screenshots with suspicion until confirmed.
- Treat orange rainfall and Signal No. 3 as your personal decision triggers for school, work, and travel.
- Know your barangay's evacuation center before the red warning, not during it.
Sources
- PAGASA color-coded rainfall warnings — Official Gazette of the Republic of the Philippines.
- Modified Tropical Cyclone Wind Signal system, effective 23 March 2022 — DOST-PAGASA.
- Gale warnings and thunderstorm advisories — DOST-PAGASA.
- PAGASA heat index categories.