December in Phoenix, Arizona, presents a distinct contrast to the holiday weather experienced in most of the United States. While much of the country contends with freezing temperatures and potential snowfall, the Valley of the Sun offers a warm and inviting escape. This month marks a transition period, shifting from the milder autumn days into the cooler, yet still comfortable, winter season. Understanding the specific weather patterns, average temperatures, and what to expect allows visitors and residents to plan activities with confidence.
December Temperature Overview
The primary allure of a Phoenix December is its moderate climate, which stands as a major draw for "snowbirds" and tourists alike. During this month, the city experiences its most pleasant weather, characterized by low humidity and abundant sunshine. The intense summer heat has completely dissipated, replaced by conditions that are ideal for outdoor exploration. Daytime warmth is consistent, but the cool evenings provide a comfortable balance, making it a perfect time for a wide range of activities.
Average High and Low Temperatures
Weather data for December in Phoenix reveals a reliable and predictable pattern. The average high temperature typically settles around 67 degrees Fahrenheit (19 degrees Celsius). This is warm enough to enjoy the outdoors without the need for heavy clothing or sun protection, though a light layer might be welcome during the midday peak. Conversely, the average low temperature drops to approximately 44 degrees Fahrenheit (7 degrees Celsius). This significant day-to-night temperature swing is a hallmark of the desert climate and requires planning for varying conditions throughout the day.
Sunshine, Rainfall, and Humidity
Beyond temperature, December offers excellent conditions regarding precipitation and sunshine. The month is one of the driest of the year, with minimal rainfall disrupting the generally clear skies. Residents and visitors can expect to see the sun for the vast majority of their waking hours. This reliable sunshine is a key factor in why Phoenix remains a popular destination during the winter months. The low humidity further enhances the comfort level, preventing the sticky feeling common in other regions during the cooler months.
Sunshine: Phoenix receives an average of 10 hours of sunshine per day in December, making it one of the sunniest months of the year.
Precipitation: The average rainfall is approximately 1 inch (25 mm) for the entire month, often falling as brief, isolated showers.
Humidity: Average humidity levels remain low, typically ranging between 30% and 50%, contributing to the dry and comfortable air.
What to Pack for December
Packing for Phoenix in December requires a strategic approach to handle the daily temperature variance. Mornings and evenings are significantly cooler, necessitating layers for warmth. However, the middle of the day can feel quite pleasant in just a t-shirt. The key is flexibility. Light sweaters, long-sleeve shirts, and comfortable pants are essential for the cooler parts of the day. Sun protection, including sunglasses, a hat, and sunscreen, remains crucial during the sunny midday hours.
