Temperatures in Harpswell can be quite different than those in Portland, where NOAA has their nearest weather station. I've been keeping track of those differences to determine what normal temperatures are in Harpswell (normal daily Portland temperatures are based on the 30-year average from 1981-2010). My weather station is much closer to the ocean than the Portland weather station that is at the airport. Mine is also on a peninsula, so the greater influence of the ocean temperatures tends to moderate air temperatures in the summer and winter.
Up until December, all 11 winter months (December-February) since January 2011 had average temperatures that were warmer in Harpswell than Portland (on average by about 1 degree). In December, Harpswell was 1.5 degrees cooler than Portland - a very big change from previous winter months. Not sure why that would be, especially since water temperatures are warmer than normal this winter. Perhaps it is just a random weather feature. So far, January has been warmer in Harpswell than Portland, so perhaps December was just another example of the randomness weather.
All 12 summer months (June-August) had cooler average temperatures in Harpswell than Portland. Spring temperatures in Harpswell and Portland are about the same; fall temps also tend to be warmer in Harpswell, like winter. The blue dots on the graph show the selected differential that I used in 2014 to determine normal temperatures in Harpswell. Clearly 4 years is not enough time to determine the long term average differential; it's a work in progress.
Up until December, all 11 winter months (December-February) since January 2011 had average temperatures that were warmer in Harpswell than Portland (on average by about 1 degree). In December, Harpswell was 1.5 degrees cooler than Portland - a very big change from previous winter months. Not sure why that would be, especially since water temperatures are warmer than normal this winter. Perhaps it is just a random weather feature. So far, January has been warmer in Harpswell than Portland, so perhaps December was just another example of the randomness weather.
All 12 summer months (June-August) had cooler average temperatures in Harpswell than Portland. Spring temperatures in Harpswell and Portland are about the same; fall temps also tend to be warmer in Harpswell, like winter. The blue dots on the graph show the selected differential that I used in 2014 to determine normal temperatures in Harpswell. Clearly 4 years is not enough time to determine the long term average differential; it's a work in progress.