...Northern and eastern Maine summer (June through August) climate narrative for 2015...
Overall, the meteorological summer of 2015 featured near average (1981-2010 averages) temperatures that ranged from 1 degree below normal to one degree above normal across the region. At Caribou, The average temperature of 63.6 degrees was three tenths of a degree (0.3F) above normal. At Bangor, the average temperature of 65.6 degrees was 1 degree (F) below normal.
Precipitation as is usually the case was more variable geographically across the region, but it was in general drier than normal with 50 to 90 percent of normal rainfall in parts of eastern Aroostook and western Hancock counties. Rainfall ranged From 110-150 percent of normal across most of the remainder of the region. Locally precipitation approached 200 percent of normal in parts of southern Piscataquis and southern Washington counties.
At Caribou, a total of 11.62 inches of rain was observed, which was just 3 tenths of an inch above normal. At Bangor, a total of 8.69 inches of rain was observed, which was 36 hundredths of an Inch (0.36") below normal.
The summer started on a very cool note, and in fact was the 5th Coolest June on record at Bangor and the 11th coolest at Caribou. It was only the 2nd time on record that the temperature failed to hit 80 degrees during the entire month of June at Caribou. The 2nd was an unusually cool day across the region with temperatures not getting out of the 40s, only the 2nd time in history this has happened at Bangor during the month of June.
The cooler than normal weather continued in July, although compared to long term averages it was not so dramatically cool as June. Precipitation was highly variable and ranged from well below average across large parts of Down east Maine to well above normal in northwest Maine.
There was a distinct lack of thunderstorm activity in July, with no severe thunderstorms observed until the 27th. Late July and early August were very active with numerous severe thunderstorms with either large hail or damaging wind gusts.
August began with near normal temperatures, but was followed by a 10 day stretch of very warm and humid weather. In fact, there were 10 consecutive days with a high of 80 degrees or warmer at Caribou, which was the most on record. It was also the warmest August on record at Caribou. The most significant weather event was very heavy rain in southern Washington county on the morning of the 26th that produced up to 9 inches of rain and produced Flooding.
