Yellow Alert: Rainstorms Flood Southern Boroughs; Metro Network on Safety Pacing Citywide

Intense afternoon storms on May 19 triggered a Yellow Alert across Mexico City as heavy rainfall and possible hail struck Coyoacán, Iztapalapa, Tláhuac, and Tlalpan — the capital's four most flood-prone southern and eastern boroughs. Moderate rainfall also affected Benito Juárez, Cuauhtémoc, Gustavo A. Madero, Iztacalco, and Venustiano Carranza. Multiple arterial roads flooded, generating severe traffic delays citywide. The STC Metro activated safety-pacing (marcha de seguridad) across the full 12-line network to prevent accidents on flooded track approaches. SACMEX deployed pumping equipment to priority zones under the rainy season action plan activated May 15 — when the city had pre-positioned crews at 56 flood-risk points. Environmental scientists from the Universidad Iberoamericana warned that Mexico City's accelerating loss of urban vegetation — replaced by impermeable concrete and asphalt across the Valley of Mexico — is amplifying flood risk with each rainy season, as natural soil infiltration has been largely eliminated, forcing drainage infrastructure to absorb 100% of storm runoff with no buffer. CONAGUA forecast persistent heavy rains, hail, and electrical activity across the valley through May–June.