Two days after the remnants of Hurricane Ida brought a sudden and ferocious storm to the Mid-Atlantic region, residents on Friday confronted the fallout from a downpour that killed at least 43 people across four states and illustrated with frightening clarity the threat posed by a changing climate.

In New Jersey, where at least 23 people were killed, many residents died in their cars, trapped by rapidly rising floodwaters and drowned without means of escape. In New York, at least 15 were dead, 13 in New York City, many of them submerged in ground-level apartments that they may have sought out for their affordability.

In Connecticut, a 26-year veteran of the state police force was killed when his car was swept away by floodwaters. And in Pennsylvania, at least four people died in counties close to the swollen Delaware River.