On Thursday, April 24, 2025, the Environmental Commission of the Megalopolis (CAME) confirmed that Phase 1 of the environmental contingency remains active in the State of Mexico (Edomex) and Mexico City (CDMX). This decision comes in response to persistently high levels of pollution recorded since the previous day, with the aim of protecting public health and minimizing exposure to contaminated air.
The CAME's report, issued at 10 am, indicated that the measure was activated on Wednesday afternoon to reduce emissions. The weather conditions are expected to remain similar throughout the day, featuring clear skies, strong solar radiation, and little wind. These conditions are not favorable for the dispersion of pollutants, as a high-pressure system continues to affect the central region of the country. The lack of cloud cover and stable atmospheric conditions contribute to the accumulation of ozone and other harmful substances.
Authorities have advised residents to avoid outdoor activities and exercise between 1:00 PM and 7:00 PM, the hours when air quality tends to deteriorate. Additionally, they recommend reducing fuel use at home by limiting shower times to a maximum of five minutes and using covered containers while cooking.
As part of the contingency measures, certain vehicles are prohibited from circulating between 5:00 AM and 10:00 PM. This includes vehicles with verification hologram 2, as well as those with hologram 1 whose last digit is 1, 2, 3, 5, 7, or 9. Moreover, cars with hologram 0 and 00, green sticker, and plates ending in 1 and 2 are also restricted. Vehicles without verification, such as foreign cars or those without proper documentation, are not allowed on the roads during this time.
The next report from CAME, along with the Secretary of Environment and Natural Resources and local environmental authorities, is scheduled for 3:00 PM on the same day. This update will evaluate air quality and the evolution of weather conditions.
By 3:00 PM, CAME confirmed that the environmental contingency remains in effect, attributing this to the ongoing influence of the high-pressure system that has persisted for four days. The combination of weak winds and intense solar radiation continues to favor ozone formation, leading to very poor air quality in the region.
As a result, a Double Hoy No Circula program will be implemented for Friday, April 25, 2025. The restrictions will apply to private vehicles with verification hologram 2, those with hologram 1 and plates ending in 1, 2, 3, 5, 7, and 9, as well as vehicles with hologram 0 and 00, green sticker, and plates ending in 1 and 2. Additionally, units without a verification hologram, including demonstration vehicles and those with tourist passes, will face the same restrictions.
In an effort to mitigate the impact of the environmental contingency, authorities are recommending that citizens continue to work remotely and conduct errands online to minimize travel. They also advise avoiding the use of air fresheners, aerosols, paints, and any products containing solvents. Refueling should be done after 6:00 PM and before 10:00 AM, and residents are encouraged to check for and repair any leaks in domestic gas installations.
As the day progresses, the CAME and the Secretary of Environment will continue to monitor the situation closely. A new report is expected to be released at 8:00 PM on April 24, 2025, which will determine if the contingency measures will extend into the following day.
In a turn of events, the CAME announced that as of 6:00 PM on April 24, the environmental contingency will be lifted. This decision follows a drop in hourly ozone concentrations below the established thresholds. Meteorological models suggest that ventilation conditions will improve, allowing for better air quality in the coming days.
Despite the lifting of the contingency, authorities remain vigilant and will continue to assess air quality and weather conditions to ensure public safety. As part of the ongoing efforts to manage air pollution, the Hoy No Circula program will still be in effect for Friday, April 25, 2025. Vehicles that will not be allowed to circulate include those with blue stickers, as well as those with plate terminations of 9 and 0, and hologram 1 and 2.
The measures taken by the CAME highlight the ongoing challenges faced by Mexico City and the State of Mexico in combating air pollution. With a combination of regulatory measures and public health advisories, officials aim to protect the health of residents while working towards long-term solutions for air quality improvement.
