26-03-2025
Maple Weekend: Weather's impact on sap production
BUFFALO, N.Y. (WIVB) — This Saturday and Sunday, March 29-30, mark the second and final weekend of New York Maple Weekend, a celebration of maple syrup producers in Western New York.
A lot of work goes into maple syrup production, and almost everything about the process is controlled by humans — except the weather.
🍁 List: WNY locations participating in Maple Weekend
Maple trees require an extremely specific environment for the best sap production. Ideally, to maintain steady sap flow, temperatures overnight have to get to the freezing mark or below. Then, during the day, high temperatures must warm up to well above freezing. This cycle creates a freeze-thaw pattern, which causes pressure within the tree, leading to the movement of sap.
Of course, late winter to early spring in Western New York does not have perfect temperature patterns like this. What exactly happens to maple trees and sap production during the cold snaps and warm spells we experience during maple season?
While it's good for sap flow when temperatures are well above freezing during the day, if it stays above freezing overnight and that trend continues for a few days, it will inhibit the tree to start budding. This will make the tree's metabolism shift towards the growth of the tree rather than the production of sugar, overall decreasing the quality of the sap for maple products.
Last week, our Kelsey Anderson and Dave Greber interviewed Nick Wendel of Wendel Family Maple in East Concord on News 4 at 5:30, and he mentioned the weather that we've been seeing this month and how it affected maple production.
'We're very, very much weather-related,' Wendel said. 'We need nights below freezing, days above freezing. … It was a little bit warm here recently — a little bit too warm.
'Sugar makers like that cold, wet weather,' he added. 'More mud, more sap.'
During long cold spells, the tree tapping process gets delayed. When temperatures drop below freezing overnight, the flow of the sap slows significantly or stops completely. Then, if temperatures struggle to get above freezing during the day, the sap will still not be flowing, making it challenging to harvest the sap. This could also delay the start of maple season, making the already limited time frame for tapping shorter overall.
The majority of March hasn't been too bad as far as low temperatures go. There were only four days where temperatures were well above freezing (37 degrees or more), and two of those days were consecutive. For the rest of the month, temperatures stayed near or below freezing.
High temperatures for the month have been mainly above average, even seeing three days of 70+ degrees, two of those days being record breakers. But, even after those days, the low temperatures overnight into the next day were just a couple of degrees above freezing. In general, March in Buffalo has had good conditions for maple syrup making.
As far as the forecast for the second round of Maple Weekend, it's looking to be a soggy and muddy one. It'll be best to have rain gear and mud boots handy if you're planning to be outside, or venturing out to a sugar shack. Temperatures are looking to stay mild during the daytime, though, with highs in the mid to upper 50s.
Sara Stierly is a meteorologist who joined the 4 Warn Weather team in February 2025. See more of her work, here.
Copyright 2025 Nexstar Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
