The warming Gulf of Maine has contributed to Maine's recent hot weather
Temperatures were a bit cooler around Maine on Wednesday, but the past week has seen near-record heat across northern New England. A daily record high was set in Portland. Concord, New Hampshire hit 90 degrees for a full week. And it all comes amidst the state's ongoing drought.
Maine Public's Robbie Feinberg spoke with Derek Schroeter, a meteorologist at the National Weather Service office in Gray, who says Portland saw three consecutive days of high temperatures above 90 degrees.
Note: This interview has been lightly edited for clarity.
Derek Schroeter: And that is kind of our rule of thumb. Rough definition for a heatwave is three days in a row of of 90 degree temperatures. And we also had a record warm, low temperature of 74 degrees where the previous record warm, low temperature was 71. So not cooling off at night. And then that led into another record high of 95 degrees on the eighth and that tie the previous record of 95. That was set back in 1949. So certainly a notable warm period, or hot period for us here in northern New England.
Robbie Feinberg: And, Derek, when you were talking about those warmer nighttime temperatures, that's something that I don't remember as much necessarily from even even my childhood, I mean, how unusual is something like that?
Really from the late 1990s. Up until now, there's been an audible trend where we're seeing more days of low temperatures not dropping below 70 degrees. So back in 2020, that I was just referencing, that actually had a warmer summer up until this point, then we have. The low temperature there didn't drop below 70 degrees for nine days during the summer. And so usually what that means is, you know, most people are resorting to running their air conditioners at night, as opposed to being able to open up the windows to cool off the house. And a lot of that can be attributed to the Gulf of Maine sea surface temperatures have actually been running well above normal. For the last few years, I'm not a thorough expert on the reasons why the Gulf of Maine is warming by you know, sea surface temperatures, you know, as a whole along with the planet as a whole is seeing rising temperatures both in the atmosphere and in the oceans. So the thing with the warm Gulf of Maine is that that, you know, kind of provides, you know, our buffer in the wintertime from keeping us too cold and also a buffer in the summertime from keeping us getting too hot. But as sea surface temperatures have been running several degrees above normal, that can contribute to the lack of cooling off that we see at nighttime.
Yeah, and we've also obviously still got this ongoing drought in Maine. Where do things stand right now? Do we still need a lot of precipitation?
You know, right now over a one month period here in coastal Maine, we would need on the order of six and a half inches of rain in the next 30 days to completely eliminate the drought. We are heading into you know, the ramp up of the tropical season and usually, oftentimes, we see droughts and then those droughts come to an end when remnant tropical system tracks over the area and drops widespread three to five inches of rain.
And what would you say we should expect kind of moving forward? Should we expect more of this hot humid weather with a warming climate?
You know, an analogy that I use is that you know, a weather event is maybe one at bat where the climate is the batting average. Anybody can, you know, at one at bat hit a home run but over the course of the season, you know, they can still have a very poor batting average. And the overall thing is, you know, is we have the Gulf of Maine is still running well above normal for sea surface temperatures and as long as that continues, I expect you know that to be a source of humidity and that also attributing to our inability to cool off at nighttime.