McAlester has hot, humid summers — daytime highs of 35°C / 95°F are routine in July and August — and cool to cold winters that occasionally bring ice storms. The best months are April through early June and September through October, when the surrounding hills are green and the air is bearable.
The single event worth timing a visit around is the Italian Festival, held over Memorial Day weekend in late May. Tens of thousands of people descend on Krebs and McAlester for pasta dinners, sausage sandwiches, bocce, grape-stomping, and a parade. If you have any interest in the town's Italian heritage, that is the weekend to be here. Book a room well in advance.