2017 Foliage Report | How a Heat Wave Can Stall Progression of Fall Color

New Englanders don’t get many true beach days after autumn shows up on the calendar. Nor do they usually see lakes crowded with water-skiers at the end of September. But in the midst of a rare-to-unprecedented heat wave this year, people across the region have been sweating up a storm during what would normally be crisp autumn outings. Fall fairs have been sweltering, and it was so hot last Sunday that Gillette Stadium ran out of bottled water during the Patriots game. As for my family, we opted to wait until late afternoon for our trip to the apple orchard this weekend, hoping it would cool a bit. Hot apple cider? No thanks! And there was zero chance I would turn on the oven to bake an apple crisp afterward. So, how hot has it been? Burlington, a gathering point for many early leaf-peepers in northern Vermont, provides a perfect case study. Through the first 10 days of September, Burlington was nearly 5°F below normal. This kick-started the fall colors early, with brilliant reds dotting the landscape by mid-September in both Burlington and other parts of northern New England.

That temperature shortfall has been completely erased, and Burlington now sits at 3°F above average for the month — quite the swing. This bout of heat was particularly excessive. A heat wave is defined as three consecutive days with temperatures above 90°F. Burlington had an official heat wave whose three record highs supplanted previous records by more than 5 degrees each. And the water of Lake Champlain is 72°F, the warmest it’s been in autumn since records have been kept.

Northern Vermont isn’t the exception. Millinocket, Maine, hit 91°F this week following three days of temps over 85°F. Meanwhile, the overnight lows struggled to stay below the normal daytime high of 63°F. And at New Hampshire’s Mount Washington Observatory, where the record high is only 72°F, they’ve already seen temperatures in the sixties 10 times this month. And let’s be clear: This is not ideal for fall color in the most northern areas of New England. 

2017 FOLIAGE UPDATE: HEAT WAVE STALLS FALL COLOR

We know that as the foliage season starts, the best colors are brought out by warm sunny days, cool nights and occasional and adequate rainfall — the exact opposite of what we are seeing right now. In response, the progression of fall color that we had been seeing in northern New England has stalled —  in a holding pattern at best, and regressing at worst. Some of the early-turning leaves that were speckling the landscape with the brilliant reds we highlighted last week have browned and fallen; in the heat, little new color has emerged behind them. Thus there was still plenty of green all the way up to the Canadian border on my trip through New Hampshire this weekend, and we’re hearing similar reports everywhere.

PREDICTIONS FOR NEXT WEEK

The good news is that by the time this piece is published, the heat wave will have broken; in its wake, a long stretch of seasonal weather has been forecast. There might even be some frost in northern areas by the weekend. With that, we should see the rapid acceleration of the fall pageant in the areas that typically turn first.

We are hopeful that when this happens, the colors will come in strong and vibrant. But there is also a risk that the leaves will drop quickly after this hot, dry spell, especially given the lingering drought stress from last year. With this type of unprecedented weather, there’s little historical record for comparison to see where it goes from here. We just have to wait and hope. For those looking to get out and see some fall color this weekend, my advice is very similar to what I gave for last weekend. Areas in the far north with elevation are your best bet. Vermont’s Northeast Kingdom and the northern Green Mountains have held their color. Leaves should turn rapidly in New Hampshire’s Great North Woods. In Maine, the western mountains as well as the Crown of Maine will have picturesque spots.

Looking for a silver lining to all this? The adjusted timetable could very well put a lot of the region at or near peak foliage for the coming Columbus Day weekend. And that would make the many visitors to the area appreciative of our absurd heat wave.

As the colors come on this week, we will continue to look for your reports. As always, be sure to visit NewEnglandFoliage.com for our weekly 2017 foliage forecasts and reports, as well as our live peak foliage map and everything else you need to plan your foliage trip in the region. On Instagram? Tag your photos with #MyNewEngland for a chance to be featured on our feed. Enjoy the return to fall-like weather, and with any luck, some bright colors will quickly come in!

SEE MORE: The Worst Weather Disaster in New England History Weekend Foliage Planner 10 Best Fall Road Trips in New England

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