Cities across the country are sinking, especially in Houston and other cities in Texas, posing significant threats from flooding and damage to infrastructure.

A more active severe weather pattern is ahead beginning later this week in the Plains and Midwest that could produce large hail, wind damage and possibly a tornado threat.

The storm system that has been soaking the South for days is now on the move. That means localized flash flooding is possible in the mid-Atlantic Tuesday.

Apple snails are an invasive species generally banned from import and movement across state lines. Watch this video to learn about the environmental destruction they can cause, the potentially deadly risk to humans and why wildlife officials in southern states like Texas, Georgia, North Carolina and Louisiana want you to look out for the snails’ bright pink eggs.

Ever looked up and spotted a glowing ring around the sun, or what seemed like a second sun hanging in the sky? From shimmering halos and sun dogs to ghostly Brocken specters and wave-like Helmholtz clouds, we’re breaking down the science behind these jaw-dropping sky illusions - nature’s own surreal art show.