While August is, without a doubt, part of the classic summer duo of July and August, this second half of summer seems slightly lost in terms of identity.
It almost feels like July’s little brother or sister, standing in the shadows behind its sibling’s unequivocal distinction as Summer, with a capital “S.” You can almost hear the conversation, “August? Oh yeah, that the “other” summer month.” “Oh, sorry August. I didn’t see you behind good ol’ July.”
Admittedly, August doesn’t usually bring anything new to the table. Hot and humid? Yes, more of the same from July. Afternoon thunderstorms? A summer habit established several weeks ago. Warm, stuffy nights? You’ve likely figured out your routine of opening the house at night and closing it up during the day to keep it cooler. In so many ways, August appears to be an extension of the summer contract signed by July – just keep doing what you’ve been doing, and all is well.
This is no revelation. August has been playing second fiddle to July, almost since July came into existence. The Romans started with an agricultural calendar from Greece, adding such things as January and February. Julius Caesar realized that deficiencies in the calendar had significant impacts to a well-run empire (or efficiently-taxed empire), and consulted the best minds in astronomy and mathematics to develop what is now known as the Julian Calendar. The Roman senate honored him by renaming the Quintilis, the fifth month of the year (the Roman calendar started March 11) after Julius Caesar, and so we have July, the first month to be named for an actual person. Caesar’s nephew, Augustus, made addition calendar reforms, and following the lead of Julius, had the next month, Sextilis, renamed after him, and thus we have August following July. Once again, August, rather than owning something unique, takes its naming after the tradition established by July.
What does all of this have to do with the weather in August? Mirroring the calendar that gave these months their names, August, in so many ways, continues the meteorological themes known so well in July. Temperatures and humidity, for example, demonstrate little change from July through August. Our summer temperatures climax near July 18, as the average maximum and minimum temperatures, reach their highest figures of the year. However, the changes through the months of July and August only fluctuate by a few degrees. Using the records at the Fairbanks Museum in St. Johnsbury as a warm, valley location, and Sutton to represent the higher terrain near 1,500 feet in elevation, we find July’s average daily high ranges from 81 to 83 degrees in St. Johnsbury, and only 74.5 to 75.5 degrees in Sutton.
Nighttime low temperatures show a similar consistency, varying from 55 to 58 degrees at the Fairbanks Museum, and only 53.5 to 55 degrees in Sutton. During August, with the daylight decreasing by 45 minutes by the end of the month, it does cool off, mainly during the last week. The maximum temperatures in St. Johnsbury slip from 81 to 78 by Aug. 21, then drop another two degrees by the end of the month. Similarly, Sutton only drops from 75 to 74 degrees during the first three weeks but falls another two degrees during the last week. Nighttime lows offer very similar trends. Rainfall reflects the long duration of summer weather through the two months, with no strong trend up or down. The Fairbanks Museum record hints that the number of days of rainfall decreases ever-so-slightly, from 13 days in July to 12 days in August.
This stability favors many summer activities. Outdoor plans, while not infrequently interrupted by summer showers and thunderstorms, still work out more often than not, owing in part to the nature of summer precipitation. Showers and thunderstorms last for a few hours or less most of the time, while the colder weather storm systems feature periods of rain or snow for several hours. Showers and storms don’t extend over wide regions, but instead, deliver localized events, soaking one area, while passing north or south of a neighboring village or town. Our gardens, as well as larger market gardens and crops, enjoy relatively consistent growing conditions, with the greatest variation coming from rainfall. The more shallow root systems of seasonal plants are more sensitive to short term periods of excessive rain or dry episodes. During the past 30 years, August recorded 20 out of the 30 years with near or above normal rainfall, though 4 of those years had a serious surplus of rain. Only three of those years, 2001, 2002 and 2014 saw less than 2 inches of rain, which meant rainfall was short, but it always rains.
Perhaps August doesn’t mind taking a supporting role in summer. No pressure, no expectations, and usually, no complaints,
Mark Breen is the senior meteorologist at the Fairbanks Museum and Planetarium, and for over 30 years he has been the morning voice of weather on several local radio stations, as well as Vermont Public Radio’s an “Eye on the Sky.”