THE VERMONT WEATHER BOOK by David Ludlum (Vermont Historical Society, 1996)
CONTINUED from PAGE 1:
August brings “those lazy, hazy, crazy days of summer” of popular song fame. The Bermuda High continues to be a major factor in controlling the weather. On occasions its western arm may extend inland over the Carolinas and Virginia, and then heat and humidity are borne from the Gulf of Mexico on the wings of southwest and west winds to the Green Mountains. An enervating stretch of several days may ensue. One late August heat wave of southern origin began on August 28, 1973, with temperatures rising to 89° or more at Vernon in the southeast for nine consecutive days. In recent years the highest temperature during August reached 102° at Bellows Falls in 1955, and the lowest dropped to 25° at South Londonderry in 1965.
Temperatures exhibit a general decline from the July highs, but the lowering is small, about 2.3 degrees statewide. The solar input is only 85 percent of what it was in June. Bellows Falls in the southeast has the highest mean temperature with 67.8°, but this is about equal to Burlington’s 67.1° in the northwest. The waters of Lake Champlain retain their summer heat throughout the month, accounting for the high figure at Burlington. In contrast, Newport in the northeast averages a mean of 64.7°, or 2.4 degrees below Burlington.
Precipitation shows a decline of 10 percent from the July averages. The wettest places are on the high elevations of the western slopes of the Green Mountains and across the northern plateau. Several stations reach above the 4-inch level. Across the north, Burlington with 3.87 inches and Newport with 4.32 inches are well above the low elevation locations in the south. The entire Connecticut Valley lies in a rain shadow, running from 3.54 inches at St. Johnsbury in the north to 3.25 inches at Union Village Dam near White River Junction in the south-central part, the lowest in August for any Vermont station.
A familiar sound on an August evening comes from the katydids who stridulantly rub their wings together and maintain a cacophonic dirge all night. The appearance of the katydid is supposed to be a warning that summer is waning and frost is in the offing. These grasshopper-like insects emerge from their eggs in late summer, lay their own batch, and pass away with the first frost of autumn, all in about a six-week cycle in northern climes such as Vermont. Though light frosts may be experienced from time to time during August, it is usually the last half of September that brings a killing frost. But there have been exceptions. The famous summer of 1816 witnessed the end of the growing season in some northern localities on August 21 when a killing frost cut down the corn, vines, and tender vegetables, and in more recent times a black frost occurred in the Northeast Kingdom on August 18, 1918, to end the shortest growing season known, only 59 days. On that date the temperature dropped to 32° at Chelsea and to 33° at Bloomfield, Hyde Park, and Woodstock.
Tropical storms have become a threat in low latitudes in July, and during August even full-fledged hurricanes may move north and affect Vermont. Ex-hurricane Belle crossed the state on August 10, 1976, bringing deluges of tropical moisture to southern and central sections along its track. Many remember the winds and rains attending Hurricane Carol on August 31, 1954, as it roared northward through New Hampshire. Way back in Vermont history on August 19, 1788, a tight-knit hurricane packing tremendous power caused a tree blowdown that probably exceeded the forest devastation of the Great September Hurricane of 1938.
