Average daytime summer temperatures range from approximately 55 to 78 degrees Fahrenheit (13 to 26 degrees Celsius); average daytime winter temperatures are about 5 to 30 degrees (-15 to -1 degrees Celsius). Anchorage has a frost-free growing season that averages slightly over 100 days.Average January low and high temperatures at Ted Stevens Anchorage International Airport (PANC) are 11 °F/23 °F (-11 °C/-5 °C) with an average winter snowfall of 75.5 inches (192 cm).The weather on any given day and indeed for entire seasons can be very unpredictable.verage daytime summer temperatures range from approximately 55 to 78 degrees Fahrenheit (13 to 26 degrees Celsius); average daytime winter temperatures are about 5 to 30 degrees (-15 to -1 degrees Celsius). Anchorage has a frost-free growing season that averages slightly over 100 days.