Recent Purple Alerts in Mexico City: A Serious Warning
In 2025, the purple alert for rain, the most severe level of the Protección Civil’s traffic light system, has been activated four times in Mexico City. These intense rainfalls have not only caused flooding and standing water but also disrupted traffic, delayed public transportation, and turned daily mobility into a significant challenge.
Key Dates of Purple Alerts
- June 29 in Álvaro Obregón
- August 9 in the same alcaldía
- August 10 in Cuauhtémoc
- September 2 in Gustavo A. Madero
The Rain Traffic Light System in Mexico City: Understanding the Colors
The early warning system classifies the intensity of precipitations into different levels:
- Yellow Alert (15 to 29 mm of rain): warns about light rains that, combined with other factors, may cause minor flooding.
- Orange Alert (30 to 49 mm): heavy rains capable of causing greater impacts.
- Red Alert (50 to 70 mm): very intense rains with a risk of damage.
- Purple Alert (more than 70 mm): the highest level, reserved for rarely recorded intense rains that can cause severe damage.
A City Increasingly Vulnerable to Heavy Rainfall
Mexico City has experienced an intense rainy season in 2025. For instance, June was one of the wettest on record, with 337 cubic meters of water accumulated, more than double the historical average. In areas like Álvaro Obregón, up to 107 mm of rain fell in a single day, explaining the repeated activations of the purple alert.
Experts from UNAM point to several factors: the urban heat island effect, loss of green areas, rapid urbanization, and climate change impact. The result is a more intense and uneven rainfall regime, with localized storms capable of paralyzing an entire area within minutes.
Beyond large-scale hydraulic projects, prevention also lies in daily practices: not littering, cleaning gutters and rooftops, staying informed in real-time, and avoiding crossing currents of water.
Key Questions and Answers
- What does the purple alert for rain mean in Mexico City? It signifies extremely intense rainfall, posing a significant risk of severe damage.
- How many times has the purple alert been activated in 2025? It has been triggered four times so far.
- What factors contribute to Mexico City’s vulnerability to heavy rainfall? These include the urban heat island effect, loss of green areas, rapid urbanization, and climate change.
- What can residents do to stay safe during intense rainfall events? They should avoid littering, clean gutters and rooftops, stay informed in real-time, and not cross currents of water.
