In weather like this and pretty much all summer, red wine benefits from a slight chill before serving. If your house is warm and your bottle of wine is room temperature, it probably should be chilled down in the refrigerator for 20 minutes or so before serving.
Why? Red wines fall apart and don't taste like themselves when they're too warm.
Don't believe me? Try this experiment. Pour out a glass of red. Re-cork the bottle and chill it down in an ice bucket or the refrigerator - not as cold as white wine, obviously, but just a few degrees cooler than room temperature. Now pour out a glass of the chilled wine and compare the two.
The warmer wine will probably taste more alcoholic and flabby in structure. The cooler red will be more pulled together, the alcohol subdued, the flavors miraculously zoomed into focus.
And no, you don't have to go out and buy a wine thermometer. Just use your good judgment. And when in doubt, taste.
At restaurants, don't be afraid to ask for your server to chill down a bottle of red that seems too warm. It happens a lot. When the waiter or sommelier brings the bottle over to the table, if it's not slightly cool to the touch, ask for the bottle to be put on ice for a few minutes. And by ice, I mean an ice bucket filled with ice and water, with the bottle submerged to the shoulders.
If you don't want to sit there without anything to drink while the bottle is cooling, ask for a short pour before the waiter makes off with the bottle. Nurse it along and try to keep track of how long the wine has been chilling: sometimes the waiter forgets about it. You don't want your wine icy. But even if that happens, it won't take long to warm up again.