Out in Houston on Sunday morning, at the precipice of a statewide freeze in Texas and blackouts throughout the city, I passed two different women, each handling several cartfuls of groceries, who, speaking into their phones, noted that they “may have gone overboard.” I’d popped into Lee’s Sandwiches for a few gallons of coffee, and then into H Mart for other odds and ends. As the morning progressed, the traffic across Bellaire Boulevard worsened from a slight crawl to an impasse. Folks were stocking up in a way that’s become commonplace over the past year in the city, although the debacle to come had few precedents.