MIAMI — Helene was upgraded Thursday morning to a Category 2 storm and is expected to be a major hurricane — meaning a Category 3 or higher — when it makes landfall on Florida’s northwestern coast Thursday evening.

Helene was upgraded to a major Category 3 storm Thursday afternoon ahead of its expected evening landfall on Florida’s northwestern coast. Hurricane and flash flood warnings extend far beyond the coast up into south-central Georgia.

Hurricane Helene strengthened into a Category 4 storm hours ahead of its expected landfall on Florida’s northwest coast Thursday night as forecasters warned that the enormous system could create a “nightmare” storm surge and bring dangerous winds and rain across much of the southeastern U.