The County experienced some major temperature fluctuations during the past week with low temperatures occurring on Jan. 4 followed by high temperatures on Jan. 6.
Presque Isle experienced an 87-degree difference between those two days, with a low of -42 followed by a high of 45.
Houlton and Caribou both experienced 71-degree temperature shift, though Houlton was a little warmer than Caribou; Houlton’s Saturday high was 50 degrees with low of -21, while Caribou’s high was 45 degrees followed by a low of -26.
While Aroostook County is used to cold, meterologist at the Caribou office of the National Oceanic and Atmospheric Administration (NOAA) Tony Mignone explained that the extreme low temperatures weren’t in their usual distribution locations.
“Because there were high clouds and winds, some of the normal cold spots didn’t occur,” he explained.
The reason for the drastic shifts in temperature “basically boils down to the track of the jet stream,” Mignone said on Tuesday morning.
Mignone described that an overall northwestern flow brought some very cold air down from central/northern Canada that gave way to an intense storm system; as the storm system moved up to the west of New England, the jet stream track brought mild air from down south up through northern New England.
But as the storm system passed through to the north, with its counter clockwise circulation, “we get a flow in the jet stream that’s northwest, and the cold air comes back (like it did on Tuesday morning),” Mignone described, mentioning that a brief shift in temperatures isn’t uncommon for this time of the year.
“It’s a good thing that the warm-up doesn’t last very long, because if you get a prolonged warm period in January (which doesn’t happen too often) it can break the ice up on the rivers and then, when it refreezes, it can cause problems in the spring,” Mignone said.
Not only was the past week warm and cold, Monday was also both wet and windy.
Caribou had windy gusts of up to 47 miles per hour on Monday, and the city saw .9 inches of rain.
Further north, Frenchville had .78 inches of rain and further south, in Houlton there were 1.12 inches of rain.
The most rain fell in the Calais area, with 2.33 inches.
