FORT KENT, Maine — All of Maine was put under a flood watch Monday as mild temperatures coupled with a rainy forecast produced significant snow melt, raising river levels and creating the potential for ice jams.
According to reports from the National Weather Service offices in Gray and Caribou released Monday, the watch is in effect through Wednesday night.
Warm temperatures and a rainstorm expected Tuesday into Wednesday have elevated flood risk in all areas. Flood potential was already high due to an above-normal snowpack, river ice and rising spring stream flows.
“Temperatures will remain above freezing tonight in advance of an approaching cold front, which will cause snow to melt,” the National Weather Service said in its release on Monday. “Rain chances will also begin to increase later tonight, [and] moderate to heavy rain will occur across the region later Tuesday into Tuesday night.”
At a Monday morning conference-call meeting, the River Flow Advisory Commission was told potential for flooding around the state is “extremely high,” according to Greg Stewart of the United States Geological Services in Maine.
“A lot of it depends on how much rain we get,” he said. “The system is well primed, [and] flood potential is well above normal, especially as you get into the northern reaches of the state.”
Small ice jams were reported along the Piscataquis River as of Monday morning, and river watchers are keeping an eye on a jam on the St. John River near Dickey in Allagash.
“I suspect any ice jam in the St. John will be substantial,” Stewart said. “The [water] flow is there to get them moving, and we definitely need to watch that.”
Darren Woods, director of the Aroostook Emergency Management Agency, had been out checking river levels in central Aroostook early Monday morning. He said that the levels are rising but remain well within the banks.
“We are monitoring the rivers and remain in a holding pattern,” Woods said. “We are seeing the ice weakening and some higher levels of water, but there is still quite a bit of room for the rivers to swell before there are any problems.”
Woods said his river watchers around the region are reporting similar conditions.
Temperatures in southern Maine were expected to soar into the mid-70s on Monday, followed by up to 2 inches of rain on Tuesday, according to Tom Hawley, hydrologist at the National Weather Service in Gray.
“We will start to see some melting this afternoon, and river levels going up in response to that,” he said. “It looks like late tomorrow, we will start to see rivers approach and go above flood stage.”
Maureen Hastings of the Caribou office of the National Weather Service said about 1-1.5 inches of rain was expected late Tuesday with temperatures climbing to the 50s.
“There is still a good amount of snow in northern Maine,” Hastings said. “That snow is pretty wet, and I can’t imagine it will absorb much of that rain, so it will be pure runoff.”
By Wednesday, the rain will have moved out and conditions improved for a slower melt to the snow, with lower temperatures through the weekend.
According to the Maine Geological Survey, last week’s Cooperative Snow Survey showed the snowpack water content in all of Maine to be well above normal for the time of year. Some of that water content has likely run off over the last week but what is left will likely have become more dense and more likely to be released with rain. Snow survey crews are in the field across the state today through Wednesday, the weather service said.
Meanwhile, the U.S. Geological Survey reported that stream flows are already high due to warm temperatures, snowmelt and runoff over the last few days. While the rivers in the south are largely free of ice, more northern tributaries are still releasing ice, and northern rivers such as the St. John still had significant ice in place.
The National Weather Service on Monday said the threat of ice jams and flooding will persist through Wednesday and areas normally prone to flooding will likely see some minor flooding, with water on low-lying roadways and parking lots.
With the information distributed previously and shared on Monday’s conference call, county and local emergency managers will be activating local plans to prepare for any flooding that does occur.
NWS Forecast offices will continue to keep emergency managers and the public advised of the flood threat throughout the event.
BDN writer Dawn Gagnon contributed to this report.