Lake Louise in December

July and August offer the warmest weather and longest days, but also the biggest crowds and highest prices. This is peak hiking season when all trails are snow-free. June can be perfect - fewer crowds, wildflowers blooming, though some high alpine trails may still have snow. September is my favorite time: cooler temperatures, stunning fall colors, and the summer hordes have departed. You might catch early snow on the peaks. October brings unpredictable weather but incredible larch displays on nearby trails like Larch Valley. Winter transforms the lake into a skating rink and cross-country ski destination, but it's brutally cold - think -20°F. The lake typically freezes from December through April. Spring (May) is mud season with limited trail access and unpredictable weather. For photographers, the golden hour light is spectacular year-round, but summer offers 4 AM sunrises and 10 PM sunsets.