The National Oceanic and Atmospheric Administration has issued its 2014 national spring flood risk report. The weather service is predicting an increased threat of spring flooding in Vermont and northern New York due to continued cold temperatures that have kept the deep snow from melting.
In its annual spring flooding outlook released Thursday, the NOAA’s generalized map of the nation indicates a minor risk of spring flooding throughout the Northeast. But if you zoom in to regional maps and localized river reports, Vermont and northern New York have a heightened potential for flooding. The weather service says there are above average amounts of snow on the ground in much of the region while the rivers and streams remain frozen.
National Weather Service Burlington Meteorological Technician Nathan Foster says most basins in northern NY have an above normal potential for flooding. “ We’ve had a lot of snow in the last few weeks and a lot of really thick ice out there. So it’s all going to depend on how much rapid warming we get and if we get any heavy rain events on top of that. But there’s still a lot of snow out there to get rid of.”
Foster adds that the risk in Vermont is very similar. “The only place that we’re not thinking about above normal potential for flooding is actually on Lake Champlain. But most of the river basins have about normal chance.”
Among the rivers, NOAA’s charts show probability of flooding for the Mad River at Mooretown VT, the East Branch of the Ausable River in Ausable Forks, NY, and the Winooski River in Essex Junction and Montpelier, VT
Cornell University Northeast Regional Climate Center Climatologist Jessica Spaccio says the flooding will vary locally and regionally depending a number of factors, including ice jam risk, depth of the river and the snowpack. “This year we did have a more normal snowfall and actually some areas had above normal snowfall. Where the past two winters have been more on the mild side where we didn’t have a lot of snowpack. This year where we do have a snowpack, we worry about how quickly that melts. It’s good to have a snowpack because we want that moisture in the ground and in our rivers and watersheds. But if it melts too quickly then we worry about flooding. So it’s usually a spring worry. So this year because we do have the snowpack it is a risk. It depends on how quickly it melts, how quickly we get warm temperatures and also what the rainfall is like. If it’s a subtle melting it’s not such an issue. But rain on snow is when we can get higher flood risk.”
Clinton County NY Assistant Director of Emergency Services Kelly Donoghue says his office uses the NOAA flood outlook as a tool with other resources to help prepare for potential flooding. “The key for any spring, especially when you’re dealing with ice in the river, is you want warm days and cool nights. That way it slows the process down so that you can have a natural melt. We are going to be having some meetings with community leaders to be able to have a plan in place. You can’t project when and where it’s going to happen.”
Donoghue is hoping there will be no, or minimal, flooding this year. “It’s been a different year. So projection wise, I’ve been in this job 17 years, and to have the cold the way we’ve had it for so long and to see the solidity of the ice the way it is, it makes me a little nervous. But as long as we can get the lake to melt then obviously the ice will have a point to go out so that it doesn’t jam up on the mouths of the rivers. If people have not gotten it, I hope they have flood insurance, especially along the river banks that normally get the floods. With this year being so questionable, we just don’t know.”
The immediate forecast is for continued temperatures below normal. The National Weather Service in Burlington says highs will return to teens and twenties by Monday.
A link to the NOAA flood forecast is available here.