January 6, 2026

A train derailment on December 30, 2025 occurred in Todd County, Kentucky resulted in a highway closure and a shelter-in-place order for a nearby community.

31 rail cars were derailed in the accident, two of which were carrying  molten sulfur; one of these cars began leaking and caught on fire, causing a safety issue for the local community. Molten sulfur is sulfur heated up to a liquid form, used to make fertilizer, process metals and make batteries. In its solid form, sulfur can be brittle and create sulfur dust, so it is easier to transport in liquid form. However, molten sulfur is flammable and releases poisonous gases when burning.

The NOAA Weather Forecasting Office in Paducah, Kentucky ran multiple HYSPLIT dispersion scenarios that prompted the Todd County Emergency Management Agency to give shelter-in-place orders to protect community members.

HYSPLIT is the Air Resources Laboratory’s atmospheric transport and dispersion model. It tracks and forecasts the release of many different types of hazardous airborne substances including chemicals, smoke, ash and radioactive materials. Knowing where a hazardous airborne material will go, and the concentrations of it along the path, is critical information for emergency managers during an incident. This allows them to effectively place first responders and know how to best protect the health and safety of the public.