Hot. Hazy. Humid. These are the Dog Days of summer, when so many of us find it hard to get – or stay – comfortable.

The Dog Days of Summer is an actual natural phenomenon in the northern hemisphere. It is the hottest time of the summer, extending forty days from July 3 to August 11 (the dates can vary somewhat in different latitudes and climates).

Although many think the Dog Days’ name is derived from the way people often feel at this time — dog-tired, or dogged by the heat and humidity, the name actually refers to Sirius, the dog star, the brightest star in the night sky, which is part of the constellation Canis Major (the big dog), visible at this time.

Sirius shines most brightly in July and early August, when it rises and sets with the sun. In late July it is in exact conjunction with the sun. (The Dog Days extend twenty days before and after this conjunction.) The ancient Greeks, Romans and Egyptians all believed that the heat of Sirius joined the heat of the sun to create the hot, humid weather so common in mid-summer. But it’s actually the earth’s tilt that causes the extreme heat.

The ancients also associated the Dog Days with drought, plagues, and madness. In modern times, we see it more as a period of inactivity, stagnation, general discomfort, and plain-old “bad hair days.”

So what can you do to beat the heat and survive the hottest time of the summer without breaking the bank? Staying home and camping out in front of your air conditioner with an endless supply of popsicles may be the most appealing option. But if that’s not going to work for you long term, consider the following approaches. Many of these are not quick fixes – so you may want to wait until the Dog Days have passed to attempt them.

• Close the window shades on the sunny side of your home. If you don’t have shades, consider installing them – or curtains or draperies.

• Install ceiling fans to help cool the house. Run them when you’re at home.

• Clean or replace ventilation system filters each month.

• Install a programmable thermostat, and keep your house cooler when you’re there, warmer when you’re not.

• Have a professional conduct an energy audit of your home (NStar is offering these for free in some local towns right now). Among other things, this will help you to determine whether or not your house is adequately insulated.

• Replace an older central air-conditioning system with a more efficient “Energy Star” one. Have your central air serviced each spring.

• Shade window-unit air conditioners from direct sun to improve their efficiency.

• Replace single-pane windows with double-pane, high performance glass to reflect the sun’s rays (and reduce heat loss in the winter).

• Plant a tree. In time, it will provide valuable shade to help keep your house cool.

The Dog Days are almost over. Soon enough we’ll be complaining how cold it is outside. Consider taking some long-term steps to make subsequent Dog Days more tolerable.


By Kezia Bacon-Bernstein, correspondent
July 2008

Kezia Bacon-Bernstein’s articles appear courtesy of the North and South Rivers Watershed Association, a local non-profit organization devoted to the preservation, restoration, maintenance and conservation of the North and South Rivers and their watershed. For membership information and a copy of their latest newsletter, contact NSRWA at (781) 659-8168 or visit