Canoe Lake -1913
1.Canoe Lake precipitation downdraft
2.Hayhurst Point - Paintin Place?
3.Thomson's CairnThomson's Cairn

1.This is an example strong convection – most probably a thunderstorm.

Realistically, Tom could be looking any direction. However southwest is likely due to the fact that most convective cells move from the southwest to the northeast over Ontario and specifically Georgian Bay and areas to the east of Georgian Bay.

The showers associated with the convection appear to be the purpose behind Tom’s “record” of this weather event. There is some evidence of virga as well. However, there is much more that can be deduced. We are certainly looking at the base of a towering cumulus or quite likely, a thunderstorm.   The precipitation is more visible near the cloud base where it is still probably in the form of snow. Snow flakes fall at about 1 metre per second.  As they melt, they accelerate and thus their density in the air decreases.  This decrease in hydrometeor density makes the rain drops less apparent not to mention the fact that rain is less visible than snow to start with. Snow flakes are also large particles so that by Mie scattering, they have nil wavelength dependence on the scattering of light and most of the scattering is in a forward direction anyway.

Downdraft winds from the convection has stirred up the lake into whitecaps. As a result it was certainly windy when Tom completed his record. The  wind in fact could be what Tom wanted to record. There is no evidence of a downburst debris curl where the rain hits the terrain. Such a debris curl would be unlikely over a forest anyway as these are best viewed over dusty plains. The winds drawn down by the rain are sufficient to stir up the lake. The surface winds result as a combination of the downdraft winds associated with the precipitation and the motion of the associated convection.  In this case, the blustery winds are most likely to be southwesterlies.

The cloud in the painting is the shelf cloud formed by the downdraft lifting the warm and moist environmental air into a leading “shelf” of cloud.

2. To identify Tom’s painting location one would have to match the west or southwest horizon of Canoe Lake.

3. A good guess would be Hayhurst Point which was one of Tom’s favourite camping places. It is also the location of Tom’s memorial cairn that was constructed by J.E.H. MacDonald and William Beatty.