Yes, but it is unlikely. While OP saw temp decrease, icing is not very likely at high power.
Excerpt from Wiki:
The venturi effect can reduce the air temperature by 39 K; 39 °C (70 °F). In other words, air at an outside temperature of 38 °C (100 °F), can drop to −1 °C (30 °F) in the carburetor. Carburetor icing most often occurs when the outside air temperature is below 21 °C (70 °F) and the relative humidity is above 80 percent.[1] The risk of carburettor icing is significantly increased at partial power settings (such as when power is reduced during descent), due to the cooling effect of the partly-closed throttle.[2]