NWS: North Country flooding risk near normal for now
NORTH STRATFORD — Despite an ice jam here on the Connecticut River, officials at the National Weather Service say the potential for short-term flooding in the North Country is “near normal,” although given the snow pack on the ground, the long-term is less positive.
Tom Hawley, a hydrologist with the NWS in Gray, Maine, on Sunday confirmed that the forecast he issued on Feb. 20 still holds.
He will revise that forecast every 14 days until the end of the snow-melt season.Over the next two weeks, Hawley wrote the potential “for flooding due to ice jams in western Maine and New Hampshire is near normal. However the potential for ice-jam flooding in the long term is above normal.”
Hawley and James Brown, a NWS meteorologist, both downplayed the recent, unseasonably warm temperatures in the 40s and the rain that fell on much of New Hampshire last Friday. Although warm temperatures and precipitation are flooding factors, Brown on Feb. 21 said they’d have to be sustained for at least seven days or more.
If you had both, however, “that would send most rivers and streams right over their banks,” said Brown.
Temperatures this week are expected to drop below seasonal norms, Brown said, which will reduce the threat of flooding.
Hawley said the snow pack will continue to increase over the next eight to 14 days when precipitation may be “above normal.”
“The snow depth in New Hampshire has increased markedly over the past two weeks and ranges from 12 to 36 inches across the state with the least amounts being in the Upper Connecticut River Valley,” Hawley wrote in his outlook, adding that “In the higher elevations from the White Mountains north to the Canadian border, snow depth is generally above 36 inches.”
Soil moisture, according to Hawley who cited the U.S. Geological Survey, is above normal in most of New Hampshire, but “groundwater levels are mostly near to below normal” here and in western Maine.
Reservoir levels in the Androscoggin River Basin were 57 percent full, which Hawley noted is “14 percent above normal.”
Although flows are normal, some of New Hampshire’s rivers are covered with ice that in some places is up to two-feet thick, a situation that requires continued monitoring, said Hawley. He added that an ice jam on the Connecticut in North Stratford that was created during January’s thaw, remains in place.Hawley emphasized in his outlook that rainfall — and especially its duration and intensity — “is the most important factor in determining the severity of flooding.”
“It looks like we’re going to cool down so I don’t expect any issues with flooding for the next couple of weeks,” he said on Sunday, but entering March and beyond, weather-watchers “and anybody who lives in a flood plain should be alert.”