Source: SMHI S-HYPE · descriptive facts, not a forecast
Last measured water temperature at Halvarsnoren (September 22): 10,0 °C.
The temperature at the surface probably swings between −0,6 °C and +1,1 °C compared with the deeper water today — coldest just before first light, warmest just after the afternoon's highest sun. How large the swing is depends on how much sun the water gets, the water's size and depth, cold rain, and wind mixing the surface.
The measurements come from Grecken (~5 km away) because Halvarsnoren has no measuring point of its own, adjusted for the difference in elevation.
The temperature at the surface swings from about 10,2 °C to about 10,8 °C — warmest around 14:00.
A modelled estimate based on the day's weather, the lake's depth and the wind across the day.
What does the water temperature mean for the fishing?
The water at Halvarsnoren is currently around 10,0°. How the temperature plays in is something Huggtabell.se weighs together with weather, air pressure and moon into a huggtabell for Halvarsnoren. Today's table is free, and if you want to plan further ahead they have forecasts reaching seven days out.