Rainfall on the Vineyard has been as varied as the weather itself. There is no question that it has been hot. For much of July there were drought-like conditions, weeks of no rain, followed near the end of the month by a few hours of torrential rain.
The temperature rarely gets to 90 degrees on the Vineyard. But this summer the Island has seen the temperature hit 90 degrees three times in July and twice in June. The highest temperature recorded thus far this summer, 95, came on two days in the middle of June.
Rainfall totals for the summer and the year are not far from the average. The total rainfall for July on the Vineyard was 3.45 inches, according to the National Weather Service cooperative station in Edgartown, well above the 2.63 inch average for the month.
The roller coaster ride of lots of sun and then big showers may make this a wonderful summer for both tourist and farmer. Since most of the rain that has fallen on the Vineyard came with isolated thunderstorms, often at night, the rainfall amounts for different parts of the Island may vary.
June was dry with 1.83 inches of rainfall, but May was a soaker, with 6.84 inches.
So far this year, the Vineyard has received 24.2 inches of rain, which is more than half the annual average. During the past two years, the Vineyard has experienced above-average precipitation.
Bill Wilcox, former water resource planner for the Martha’s Vineyard Commission, continues to monitor a number of groundwater wells on the Island. Rainfall is the source of fresh water on the Vineyard; the Vineyard’s drinking water comes from the ground.
Mr. Wilcox said ground water, the Vineyard’s aquifer, is in good shape, though there is a bit of an expected drop in the level with summer.
There is a water well in the center of the Island, in the middle of the Manuel F. Correllus State Forest, which Mr. Wilcox checks throughout the year. The well is about 0.8 feet below the historical average for July. “On the other hand it is still about 1.75 feet above the minimum, recorded for the month of July. My records begin in the middle 1970s,” Mr. Wilcox said.
“The recent deluges may help the groundwater slightly. But most of that will end up resupplying soil moisture and getting sucked up into the vegetation,” Mr. Wilcox said.
Throughout the summer the Correllus State Forest fire danger sign at the intersection of the Edgartown-West Tisbury Road and Barnes Road has read “high.” In the first week of August, after two significant rainfall events, it now reads “moderate.”