Rate the Climate: Frost City

I had a dream about a climate that had never had a low above freezing. While I don't remember the numbers of the climate values, I decided to recreate a weatherbox based on the climate. Here is Frost City, a tundra with average lows never exceeding 20°F (-6.7°C). Average temperatures range from 0°F (-17.8°C) in January to 40°F (4.4°C) in July. Snow can fall any time of year, and the climate usually holds a permanent snowpack from mid-November to mid-April. However, mild spells with rain are possible any time of year. Freezing rain and sleet/ice pellets are also common, especially from October to early May. Thunderstorms are possible from March to October, often with thundersnow. Usually there are some warm, sunny days in summer that can get into the 80s F (upper 20s C). However, Frost City is in such a frost hollow that even such warm days will see nights at or below freezing. The climate is located at high elevation at 48°N, so it does not have the same extreme variation in daylight you might expect from such a cold climate.