I purchased a temperature gauge with a long wire at Walmart. It's made by Minn-kota. You can attach a small weight to the temperature probe and lower this wire and probe down into the lake and measure the water temperature at the various depths. Lower the probe down 1 ft at a time out in the deeper part of the lake and record the temperature reading in 1 ft increments. That will tell you if the lake has turned over or not. If you find a depth where the water temperature changes more than 1 deg F in less than a 1ft change in depth then you may still have a thermocline in the lake and turnover has not occurred. If the lake is the same temperature throughout the vertical profile of the lake then turnover may have occurred already. But remember if it warms back up the lake can start to stratify again if it's calm and warm. Water requires a lot of heat input before it starts to warm back up and it holds it temperature much better than air. It has a high specific heat factor. So it slowly cools or heats up, unlike the air.
Turnover can also be accelerated by high winds and cold rains during this time of the year. And any currents created by letting water out at the reservoirs **** can also help mix the lake waters and break up any thermocline. Lake's like KY lake that have hydro generation going on will have the any thermocline break up sooner than a lake of the same size and depth but with no water flowing though the system.
I am not sure just how long the wire is for the Minn-kota temperature probe but I think it's long enough to find the thermocline in most lakes. I know that the thermocline on Patoka lake can occur below 25 ft as I have another temperature probe that only has 25 ft of cable and I could not find the thermocline last fall at Patoka Lake. I went to the Corp of Engineers web site where the give the do and temp profiles on the various corps lake and found that the thermocline at Patoka Lake was around 27 ft. It was at that time I was considering buying a new DO/temp probe with the 50ft long cable! But YSI wants way too much money for that device. Oh well maybe they will have a sale someday.
Regards,
Moose1am



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