Hurricane Maria has weakened to a Category 4 storm as it closes in on Puerto Rico but remains a dangerous hurricane that threatens to decimate the power company’s crumbling infrastructure and force the government to rebuild dozens of communities.

Maria’s maximum sustained winds Wednesday morning are near 155 mph and the U.S. National Hurricane Center says the storm should keep that intensity until it makes landfall.

As of 5 a.m. EDT, Maria is centered about 50 miles southeast of San Juan, Puerto Rico, and is moving northwest near 10 mph.