Natives of The County know that snow in May, especially in the first half of the month, is not at all unusual. However, when we do get May snow, it typically does its accumulating during the night.
But on Monday, May 16th, many northeast Aroostook County communities received a period of heavy accumulating snow which occurred after sun-up. Accumulating snow began at the Presque Isle Country Club shortly after 7:45 a.m. and continued until about 10 a.m., accumulating 4-5 inches.
Now, for significant accumulating snow to fall during daylight, that far into the month of May (the 16th) is truly an exceptional weather event, and to pull off the feat, the snow had to do two things. It had to fall at a sufficient rate to overcome the marginal temperatures for snow which existed at ground-level, and it also had to overcome the solar radiation trying to melt it while it lay on the ground. (Keep in mind that the sun has gotten much higher in the sky by mid-May and we are therefore receiving its rays more directly as we head toward the Summer Solstice)
So, how did it happen, this mid-May, in-broad-daylight accumulating snow? Well, during the period during which the snow fell heavily, the temperature problem was “solved”, as the heavy snow brought down with it, some slightly colder air from aloft. And the high sun angle problem was “solved”, simply due to the rate of fall of the snow. Simply put, it fell faster than that higher-in-the-sky-equal-to-July sun could melt it. You’ll recall that as soon as the snowfall intensity let up, the snow on the ground immediately started to melt.
Some stats on this rare weather event: Caribou received the most snow on record for so late in the season. Records there go back to 1939. They officially measured 4.5 inches. Presque Isle reported 5.1 inches, and another verified report out on the Marston Road, still in Presque Isle, was the jackpot winner of all, with 8.0 inches! Meanwhile, in Perham, New Sweden, and many other northeast Aroostook communities, 6 to 7 inch reports were commonplace, however these significant accumulations did not extend all the way northeastward, to Aroostook’s northeastern border with New Brunswick. However, farther south in western New Brunswick, in Carlow (which is in northern Carleton County) I received a report of 7 inches.
In general, this was quite a geographically focused event. Down Houlton way it was merely a “whiten-the-lawn” situation, and up in The Valley, 1 inch was the common number.
There was another time the weather went wildly wacky in May, as just last week was the anniversary of what was a truly remarkable heatwave in northern Maine. A heatwave is defined as having at least three consecutive days with a high temperature of 90 degrees or higher. Well in 1977, from May 22nd, through the 24th, Caribou registered highs of 96 on the 22nd, 95 on the 23rd, and 94 on the 24th. The 96 is the hottest temperature ever recorded at Caribou, going back to 1939. The only other instance of a 96 at Caribou was on June 29, 1944.
Imagine, three straight days in the mid 90s in May, incredible! We have a rather entertaining climate in “these here parts”!
Ted Shapiro holds the Broadcast Seal of Approval from both the American Meteorological Society and the National Weather Association. An Alexandria, Va. native, he has been chief meteorologist at WAGM-TV since 2006. Email him at tshapiro@wagmtv.com.
