This month is annoying, if only because it's when all the wizened locals lecture newcomers about how the real heat is yet to come. Example: In June 1988, a young D.C. meathead hops into a cab on a 90-90 day. The cabbie comes right out with it: "It gets much, much worse." Thanks for the heads-up ,sir, but when you're in 90-90 territory, it really cannot get much, much worse.
The year 2010, furthermore, taught us all that June is a summer month and has not even a toe-touch in the region of spring. Eighteen days in June 2010 reached the mark of 90 degrees or above, giving the region a good shot at surpassing the 1980 record of 67 such days; we ended up in a dead heat.
Like many other Washington months, June is capable of good work. Given the proper celestial alignment, days in the low 80s with tolerable humidity and sweet, exercise-conducive evenings are doable. You just can't plan on it.
June Weather Power Rating: 3.5
The Smithsonian Institution doesn't technically own the National Mall, it just essentially owns the National Mall. Many of its museums and attractions, after all, border the Mall and account for millions of the visitors who descend upon it.
Then you might suppose that the Smithsonian would have some control over when its famous annual Folklife Festival takes place. The dates for this year's event: June 30 through July 4 and July 7 through July 11. In the days leading up to the event, there'll be lots of tent-erecting on the festival grounds. When the gods of extreme heat and humidity see those tents unfold, they say to themselves, "It's our time."
The twin slap of H and H will keep the festival's first-aid area hopping, as usual. Says wonderful festival spokesperson Becky Haberacker: "Mostly what we see is people who have become overheated."
That's what happens when you plant a festival in the middle of a nearly shadeless patch of land in the middle of D.C.'s most infernal time of year. Being there is like being a lump of shortening under a heat lamp. Haberacker says that the festival did try holding the event in less extreme months but ultimately decided upon the tourist-heavy weeks surrounding Independence Day. More people, more heat.
The average high for July is 88 degrees, and if that weren't bad enough, consider the following mind-blowing stat. July holds second place among all months in the average number of partly cloudy days, with 11. You might say, hey, partly cloudy days are just fine – that's a good distinction for a month to have. Yet if you burrow into the matter, note that July compiles sizzling average temperatures even with a hefty cloud cover! If you get an exceptionally clear-skied July, you're going to bake even more severely than normal. And whatever the cloud factor, July just doesn't relent. Its sweltering persistence last year gave us 21 days of 90-degree-or-greater heat. In those conditions, a four-mile run may take forty minutes or so. Drying out and then replacing your fluids can take two times that span. When you're walking around with cotton shirts swollen to three times their weight via sweat, there's just no good way to spin July. You can say you love it, but you really don't. You can say you live for the heat, but then why are you eyeing the calendar's fall months?
July Weather Power Rating: 1.0
AKA bad-rap month. In all the cultural commentary on the District, August gets slandered as the hot and humid time of year that drives Congress into recess and the whole city into an out-of-town vacation. Actually, that's not so slanderous — it is indeed an uncomfortable time.
Yet the average number of August days above 90 degrees is nine, four fewer than July. And the average high for August is two degrees cooler than it is for July. Those are two huge degrees, too. As the month progresses, you can feel just a little of July's edge dissipating in August's progressively earlier sunsets. If you're patient, you can enjoy a heavenly August evening relaxing at a local outdoor cafe or hacking at the weeds on your patio that had been given free reign all July, when it was too miserable to weed or to enjoy the benefits of weeding.
The slight livability improvement in late August, though, isn't so key for enjoyment of the outdoors as it is for the sort of expectations it feeds for early September.
August Weather Power Rating: 3.0