According to the National Weather Service's Gray, Maine folks at 1:30 PM today the storm is likely to impact the area between Merrimack and Rockingham counties the most - with up to an inch of precipitation between 2PM on Friday and 8AM on Sunday. After this batch of weather it looks dry (but not overly warm) for the next 7 to 10 days.
Given this info, and since the big lake is a bit below normal for this time of year, flows have been eased a bit to help the lower lakes and river segments deal with the current melting and runoff expected from the rain over the next few days. We know that, as of 4/8, the snow pack in the basin has about about 1.6 times the normal water content for early April - but again, there is a bit of room in the lake and the forecast is for dry conditions next week.
As a rule of thumb, for every 230 cubic feet per second (CFS) of flow difference between inflow to the lake and the discharge at Lakeport Dam the level of the lake will change by 0.01 feet (less than 1/8th of an inch) every 24 hours. We've reduced flows by 400 cfs in the last 2 days so the lake will rise about 3/16th of an inch more for each 24 hour period into the future. With the ongoing melt the lake will likely rise more than that for the next several successive days - but our management over the last 2 days has added a 3/16th of an inch "surcharge" to whatever Mother Nature does.
As always, we have our eye on both the forecast and the real-time conditions in the basin.
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