Sweeping cuts to the premier US climate agency under Donald Trump have severely hampered the country’s capacity to forecast, research and respond to extreme weather events, former government officials and scientists have warned, as the US faces a cascade of hazards fueled by a potentially historic El Niño this winter.

From the start of his second term, the president has taken aim at the National Oceanic and Atmospheric Administration (Noaa), slashing staff levels, canceling contracts and grants , and shutting down databases and research laboratories. The agency that has long been considered a global crown jewel in climate science and forecasting, has lost roughly 20% of its staff since January 2025.

The National Weather Service, which is housed within Noaa, has also taken a hit.…