Flood Potential Outlook
Issued by NWS Burlington, VT
FGUS71 KBTV 131748
Winter/Spring Flood Potential Outlook
National Weather Service Burlington VT
148 PM EDT Thu Apr 13 2017
...Spring Flood Potential Outlook /8/...
This is the eighth 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 is above normal in Vermont`s Northeast
Kingdom, the Adirondack High Peaks region, and along Lake
Champlain. Elsewhere the spring flood risk is near normal. The
flood threat is primarily driven by elevated river flows and moist
soil. The ice jam threat has ended for the season.
...Snow Depths and Water Equivalent...
Snow pack has become concentrated over the higher elevations of
the Adirondacks and Green Mountains, and is more widespread in
Vermont`s Northeast Kingdom. Snow depth and water content is
highly variable depending on elevation. Snow coverage is below
normal for this time of year.
Vermont`s Northeast Kingdom had bare ground in the valley
bottoms, with snow depths of 3 to 6 inches in the lower hills
increasing up to nearly two feet above 2,000 feet. Snow water
equivalent, or the amount of liquid water held in the snowpack,
was 2 to 5 inches in the lower terrain and 8 to 10 inches in the
Elsewhere in Vermont and the northern Adirondacks, snow was
relegated to higher terrain and ridge tops above 1,500 feet. Snow
depths were six inches to a foot, and snow water equivalent was 2
to 5 inches.
The highest summits in Vermont and Northern New York still held an
impressive snowpack for any time of year. Observations near the
summit of Mount Mansfield were over 6 feet of snow containing
upwards of 30 inches of liquid water. This water content
represents the entire winter`s precipitation that has yet to be
released. However, as spring continues these pockets of very deep
snow with high water content will become concentrated to smaller
areas, and contribute less to overall basin runoff.
Snow conditions at all elevations were fully ripe, with snowmelt
an ongoing process.
...River and Soil Conditions...
Rivers were free of ice and running freely, with above to much
above normal flows from recent snowmelt runoff. Soil moisture was
very high, as typical near the peak snowmelt period. Groundwater
levels were rising from the snowmelt as well, but remained near to
below normal in east-central Vermont from lingering effects of
last year`s dry conditions.
Frost was leaving the ground, and a layer of frost a few inches
below ground surface was thawing rapidly.
Lake Champlain remains above normal and was about 1/2 foot below
flood stage. The lake has leveled off as recent snowmelt runoff
has abated. However with very wet soils, lingering snow, and
elevated river levels it won`t take much additional rainfall to
push it above flood stage, and the flood risk along Lake Champlain
is above normal.
An active weather pattern is expected to continue through late
April, with precipitation events every few days. Temperatures will
be variable, with lows in the 30s and 40s and highs in the 50s
and 60s over the next week. The longer term 8 to 14 day outlooks
call for better chances for above normal precipitation and below
The winter/spring flood potential is above normal in the
Northeast Kingdom of Vermont, High Peaks of the Adirondacks, and
along Lake Champlain. Elsewhere the spring flood threat is near
normal. High river and Lake Champlain levels coupled with wet
soil are the primary factors in the flood threat. Snow cover is
below normal for this time of year, even as pockets of high
elevation snow remain with impressive water content remain.
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