The Lake, Right Now

reading the gauges…

Four gauges and a buoy

Surface elevation in feet above the 1929 datum, water temperature, and wind where the gauge reports it. Readings are nominally every fifteen minutes; the age of each is on the card, and a card whose reading is more than three hours old says so.

Which way it is leaning

The four gauges run a hundred and twenty miles (190 km) from Whitehall to Rouses Point, and they almost never read the same. The difference between the ends is the lake tilted in its basin — wind pushing water downwind, and the whole body then sloshing back. The seiche page is about that motion; this is its current value.

Where it is going

Wind pushes the lake downhill and the lake takes most of a day to answer, which is what makes the tilt predictable at all from a wind forecast. This is the wind-driven part on its own — the slower movement, which is runoff rather than weather, is not forecast here.

How cold it is, and how far down

The Valcour buoy reports a temperature every meter or two, from the surface to the bottom of its string. In summer the top few meters are a different lake from the water below the thermocline.

Where the boundary is going

Wind leaning along the lake tips the whole warm layer, and at this end of it the boundary can move several meters in a day.

Notes

Live: USGS National Water Information System (instantaneous values); Lake Champlain Research Institute, SUNY Plattsburgh (Valcour buoy). Outlooks: pipeline/forecast.py, scored against a bar written down before it had data.