Flood Potential Outlook
Issued by NWS Burlington, VT
FGUS71 KBTV 161603
Winter/Spring Flood Potential Outlook
National Weather Service Burlington VT
1203 PM EDT Thu Mar 16 2017
...Winter/Spring Flood Potential Outlook /6/...
This is the sixth flood outlook for the 2017 winter/spring
season. Flood outlooks are issued bi-weekly by the National
Weather Service in Burlington Vermont to summarize the flood
potential due to snowmelt and break up of river ice across central
and northern Vermont and northern New York.
The flood potential due to snowmelt is above normal in Vermont`s
Northeast Kingdom, and near normal elsewhere. Although snow
conditions have increased, there is little likelihood in the next
two weeks for a melt and rainfall episode that could contribute to
flooding. The flood potential due to ice jams has increased for
rivers in northern New York and northern Vermont.
...Snow Depths and Water Equivalent...
Snow pack has seen big additions following the significant
nor`easter this week, as well as minor snowfall events in the
higher terrain earlier in March. Snow covers 100 percent of the
forecast area again.
Snow depths in the Adirondacks of northern New York and northeast
Vermont were 20 to 30 inches in the lower elevations, and 30 to
40 inches over the higher terrain. The remainder of Vermont and
the Champlain and Saint Lawrence Valleys of New York had 12 to 18
inches of snow on the ground, with 20 to 30 inches in the higher
terrain. Mountain summits in both states had considerable higher
amounts, for example 106 inches of snow atop Mount Mansfield in
Snow water equivalent, or the amount of water held by the
snowpack, saw gains as well. Lower elevations region-wide were 1.5
to 3 inches, and 3 to 6 inches over the higher terrain. Highest
water content was centered over the high peaks of the Adirondacks,
the northern Green Mountains, and Vermont`s Northeast Kingdom.
Vermont`s Northeast Kingdom had above normal snow cover and water
content, while the remaining areas were near to slightly below
...River and Soil Conditions...
River ice increased in the first half of March with the well
below normal temperatures. River ice jams were reported on the
Salmon River in Malone, and river gages were ice affected on the
Great Chazy at Perry Mills and Lamoille River at East Georgia.
With the renewal of river ice the threat for future ice jams
cannot be ruled out entirely on northern rivers.
River flows and soil moisture were above normal, primarily still
feeling the effects from the high flows of late February.
Soils are generally frozen, with ground frost sensors showing
frost depths between 6 to 10 inches deep.
Ground water levels have rebounded from late summer low levels,
and USGS monitoring wells show most ground water levels across
the North Country were near normal.
Lake Champlain remains above normal following its rise after late
February. The lake level should trend near normal in the coming
weeks. While the probability of flooding on Lake Champlain remains
low this spring, it has increased slightly with the recent
The region will remain in a colder than normal pattern through the
end of the month. Frequent fast moving weather systems will
provide small additions to the snow cover, and temperatures will
trend below normal and mostly below freezing. The longer range
outlook valid for the last week of March calls for below normal
temperatures and near to above normal precipitation. With these
trends in mind, the risk for flood producing warm temperatures or
rainfall is low.
The winter/spring flood potential is near normal across much of
the region, except above normal in the Northeast Kingdom of
Vermont. Despite recent additions to the snowpack, the cold
temperature forecast for the next week or two poses little risk of
snowmelt flooding. River ice has re-developed on northern rivers,
and will continue to pose a risk for ice jams through the end of
It is important to note that heavy rainfall can result in
flooding at any time of the year, even in areas that have little
or no snow on the ground.
The next Winter/Spring Flood Outlook will be issued on Thursday
Access current weather conditions and forecasts on our web site