Tom Thomson sketched "Moonlight" along the Oxtongue Waterway in 1912 . After the Studio Building was open for occupation in January 1914, Thomson shared "Studio 1" with A. Y. Jackson and it was then that this painting was created with guidance from his new friend. Once again the horizon is at the very bottom of the canvas - this is another skyscape.
Tom’s motivation to “record” this particular observation – colours of the moon light and the patterns around the moon. The light around the half-moon is a good example of a corona - more on that later.
Let’s assume that this is the evening. I believe that it is easier to stay awake in the evening than it is to get up hours before dawn and fumble around for the necessary materials. This is summer so the moon rises in the eastern skies in the evening. That fact alone would make this a waxing moon which would gradually increase in size over the following week to become a full moon. Thus Tom was looking in eastward in the early evening. A correlation with the eastern horizon and tree line should be possible given the amount of detail Tom put into the profile of the terrain. The western sky would be full of thickening cirrostratus which would probably be thick enough to obscure any moon and thus make for an unexciting painting. I know this is a circuitous route but all of the puzzle pieces fit together nicely if this is indeed evening.
There is quite a bit of wave action indicated by the spreading out of the reflection of the moon across the lake. This wave action is more likely in the evening hours after a windy day. The planetary boundary layer becomes unstable during the day and the winds at the top of the boundary layer are actually mixed down to the surface. These surface winds can take a while to calm down. After a night of radiational cooling and air mass stabilization, this transfer of wind is much less likely. Lake surfaces tend to be calm in the morning because of this fact. Of course there are always exceptions to any rule and a well-developed low pressure area nearby could produce a strong wind at any time of the day. However the cirrostratus cloud tells us that the approaching low is still some distance away.