No doubt, it's been a cold winter thus far in much of Maine... or has it? Let's take a look at the numbers and compare this winter to some recent winters that had a bite.
Of course, there is much more to Maine than just Portland, however, this is where climatological data are recorded in this part of the state. For this comparison, we'll use Portland numbers with the understanding that readings have been, and will be vastly different in other parts of the state.
So far this winter, we've experienced the 17th coldest December on record at the Jetport and a January that will be remembered as one of the colder ones in recent history, thus far. The buzz word heard 'round the eastern half of the country is "Polar Vortex," the airmass normally found up toward the North Pole that plunged southward as far as the Gulf of Mexico. The result has been a January of extremes:
- five days where the temperature has dropped below zero
- 13 days with below-average temperatures (as of 1/24)
This may sound cold (and it is!), but,
- we've also seen three days where the temperature was 50° or better, and
- seven days with a high of 40° or higher.
The result, after crunching all the numbers is that January's average temperature is only 0.2° below average thus far for the month! For those who know about oil heating and "degree days" (one degree day for each degree below 65° the average temperature for the day is):
- Portland is only 14 degree days above average.
But alas, averages are often times the middle of extremes:
- 65° separates the coldest temperature at the Jetport this month (-14°) and the warmest (51°).
Let's compare this to some other recent cold snaps:
Winter of 2009/2010
- Three days with a low temperature below zero
- A seven-day stretch of temperatures below freezing
- Coldest temperature of that stretch: -16° (PWM)
You may remember this winter because the state's record coldest temperature occurred on January 16, 2010 at Big Black River, where a temperature of -50° was recorded.
Winter of 1989/1990
- Coldest December on record at PWM
- 11 days recorded temperatures below zero
- A 22-day stretch of below freezing temperatures (12/8-12/30)
- Average December temperature was 14.1° (about 10° colder on average than this past December, to draw a comparison)
- A very mild January then followed with 26 out of the 31 days of high temperatures above freezing (16 days at or above 40°)