Tropical Storm Debby drenched parts of Florida, disrupting some energy production, and wetting down a slew of energy stocks already mired in persistently low natural gas prices. No. 2 U.S. natural gas producer Chesapeake Energy (CHK) tumbled 8.5% Monday, though it's also facing a report detailing alleged land-price collusion. EOG Resources (EOG) was down 3.1%. Anadarko Petroleum (APC) and Occidental Petroleum (OXY) fell 3% and 2.7%, respectively.