After months of empty roads, lockdowns were easing and people were getting behind the wheel again. A station in Northern California was selling gasoline for a whopping $5.98 a gallon.

Then the coronavirus struck again — in a fierce way. Californians, Floridians and Texans are back in hiding, and the recovery in driving that had restored highway travel nationwide back to 85% of last year’s levels is looking more fragile than ever. As lockdowns eased and parts of the world reopened for business, driving emerged as the transportation mode of choice and offered some relief for the oil market just two months off of its worst collapse in history. But the fresh resurgence of the virus in the three states with the country’s biggest gasoline markets is threatening to take American drivers off the road and stymie what has been a remarkable recovery for oil.

Demand has been flatlining over the past few days at fuel stations across the country with concern over the surge in virus cases making it hard to predict what’s to come, according to one major operator of gasoline stations in the U.S.

Houston freeways that were starting to jam up earlier in June as businesses reopened and commuters returned to offices have emptied out again. The county declared its highest level of emergency Friday after area intensive care units reached maximum capacity. Texas Governor Greg Abbott halted plans to reopen the economy further and is rolling back the opening of bars.

Road congestion was stable at below-normal levels in the U.S. Thursday, according to data compiled by BloombergNEF. Rush hour commutes in Los Angeles last week took about 30% longer than they would have on empty roads, while a year ago the same drive averaged almost 90% longer that it would have.