Amazing record-shattering warmth
Astonishing warmth enveloped Aroostook County during the second week of November.
To put it into perspective, at our warmest time of the year in July, the average high in Caribou is 76 degrees. Well, on Nov. 10, it got up to 75.
Here were the highs that day: Caribou reached 75 (the only November day to reach or exceed 70 at Caribou), Houlton made it to 73 and Millinocket posted a 74. These were the warmest November days on record for all three locations. Records go back to 1939 at Caribou, 1948 at Houlton and all the way back to 1903 at Millinocket.
Regarding the record at Caribou, there are about 2,500 November days on record. On the previous day, Nov. 9, Caribou recorded its warmest November day on record, with a high of 69. This eclipsed the previous November record of 68 which had been set twice. Nov. 1 of 1956 and Nov. 1 of last year (2019) each saw a high at Caribou of 68 degrees.
So let’s pause for a moment. Warmest November day out of 2,500 November days is on Nov. 9. Then, the very next day, that record is not only eclipsed, but shattered by six degrees. And on that day, Nov. 10, it was already 69 degrees by 10 o’clock in the morning. I went out at noon on the 10th and involuntarily hollered, “Wow.” It was just like a summer day. Everyone was walking around in wonder.
During the entire November spell, date-record highs were set at Caribou for four consecutive days, Nov 9, 10, 11 and 12, with highs of 69, 75, 67 and 66, respectively. Date-records are records for a specific date. So the 66 was the warmest temp on record at Caribou for Nov. 12. That 66 warrants further discussion, because if you were walking around that day, temps were around 50, and it was on the breezy side. So why the 66? Because a climate day runs from midnight to midnight, and the cooler air did not arrive until the early morning hours of the 12th. It was still 66 just past midnight, so that goes in the books as the high for that date. Another feature of that particular evening was that it felt downright muggy (in mid-November.). Some locations in Southern Aroostook approached what I call the “sticky-60 threshold,” when dewpoints make it to 60 degrees, making the air feel muggy to most County folks.
So we’ve established that it was incredibly warm, but just what kind of departures from normal did we see? For Caribou, the high and low for Nov. 9 were 69 and 41, against the 30-year average of 41 and 27. So that’s 28 degrees above normal for the high and 14 degrees above normal for the low.
The high and low for Nov. 10 were 75 and 52, against that same 30-year average, meaning that high of 75 was 34 degrees above normal, while the low of 52 was 25 degrees above normal.
The high and low for Nov. 11 were 67 and 51. The average for the 11th, Veterans Day, is 40 for a high and 27 for a low. So on that day, Caribou was 27 degrees above normal for the high and 24 above normal for the low.
Finally, the high for Nov. 12 was 66, 26 degrees above normal just past midnight, before November decided to be November again.
While we were in the midst of our stunning warm spell, my memory kept being drawn back to the astounding out-of-season warmth back in March 2012, when Caribou saw three straight days in the 70s.
I decided to compare the two remarkable warm spells, that of November 2020 and the one back in March of 2012 and here is what I found:
As stunning as the November temps were, the March 20-22, 2012, “blowtorch” featured temps that were even more above normal (for that time of year) than what we just experienced. (Unfortunately, that March 2012 out-of-season warmth led directly to the Perth-Andover ice jam flood.)
The average highs for March 20-22 are 35, 36, and 36, respectively, while the average lows for those dates are 17, 17 and 18.
On those three March days, the high temperatures at Caribou were 73, 75 and 73, which were 38, 39 and 37 degrees above normal, respectively, while the low temperatures at Caribou on those dates were 37, 43 and 46, which were 20, 26 and 28 above normal.
Comparing the highs and lows for each of the remarkable warm spells, you can see that the March 2012 event was even more unusual than what we just had, in terms of departure from 30-year climatological norms.
Speaking of climatological norms, they are recalculated every decade, so sometime in 2021, we will move from using averages based on 1981-2010 data, to using data based on the years 1991-2020.
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 firstname.lastname@example.org.