December in Phoenix, Arizona brings some of the most comfortable weather of the entire year, trading scorching summer heat for mild afternoon highs and crisp desert nights. Average daytime temperatures hover around 66°F to 67°F, while overnight lows drop to an average of 44°F to 45°F. If you're planning a winter getaway or looking to escape freezing northern climates, this period offers plenty of sunshine and minimal humidity.
While the climate feels ideal for outdoor exploring, desert winters come with rapid temperature drops once the sun sets. Packing requires layers, as a warm afternoon hike can quickly turn into a chilly evening stroll. Understanding what to expect helps you build an effective packing list and plan your daily itinerary around the unique rhythm of the Sonoran Desert.
Temperature Breakdown and Daily Averages
December is statistically one of the coolest months of the year in Phoenix, but that definition is relative. While northern states battle snowstorms, the Valley of the Sun experiences a mild, spring-like transition.
- Average High: 66°F to 67°F (19°C)
- Average Low: 44°F to 45°F (7°C)
- Record Highs: Occasionally reaches the mid-70s or low 80s on exceptionally warm afternoons.
- Record Lows: Nighttime temperatures dip to 40°F or below on about seven nights a month, though freezing temperatures are rare.
Daytime highs usually peak around 2:00 PM before falling rapidly after sunset. If you plan to spend all day outside, you'll feel comfortable in a t-shirt or light sweater during peak afternoon hours, but you'll need a jacket or heavy fleece by 5:00 PM.
Sunshine, Rain, and Desert Humidity
Phoenix is famous for clear skies, and December is no exception, averaging nearly 77 percent available sunshine. You'll experience roughly 10 hours of daylight each day, with the shortest days falling around the winter solstice.
Rainfall is scarce, but December is historically one of the wetter months for the region compared to bone-dry spring months. Precipitation typically totals less than one inch for the entire month, spread across three to four damp days. Heavy downpours are rare, and thunderstorms occur only on very rare occasions. Relative humidity climbs slightly higher than during the rest of the year, peaking near 67 percent in the early morning before drying out to a comfortable 33 percent by late afternoon.
What to Pack for Phoenix in December
Packing for a winter trip to Arizona requires versatility. The key to staying comfortable is mastering layering.
- Layering Essentials: Pack lightweight base layers, long-sleeve shirts, and a mix of sweaters or cardigans. Bring a medium-weight jacket, coat, or fleece for early morning hikes and late-night dinners.
- Footwear: Sturdy hiking boots or comfortable walking shoes are essential if you plan to explore regional trails like Camelback Mountain or Papago Park.
- Sun Protection: Don't leave sunscreen and sunglasses at home. The winter sun remains strong at this latitude, and UV rays can still cause skin damage during long outdoor excursions.
- Casual Attire: Denim, chinos, and comfortable athleisure wear fit right in across Phoenix restaurants, museums, and shopping centers.
Best Outdoor Activities for December
Because the intense summer heat is gone, December is prime time for outdoor recreation in the Sonoran Desert. You can hike, bike, and golf for hours without overheating.
Desert Hiking
Trails at McDowell Sonoran Preserve or South Mountain Park offer crisp morning air and sweeping views. Start your hike around 9:00 AM once the morning chill lifts, and always carry extra water. Even though it's winter, the dry desert air accelerates dehydration.
Holiday Lights and Festive Events
Local attractions embrace the cooler weather with seasonal displays. The Desert Botanical Garden hosts its annual Las Noches de las Luminarias, lighting up desert trails with thousands of hand-lit luminaria bags and festive music. You can also explore local neighborhood light displays without melting in your car.
Golfing
Phoenix boasts dozens of world-class golf courses. December rates peak because golfers flock south for the weather, so book your tee times well in advance. Mornings can start frosty on the grass, so 10:00 AM or 11:00 AM tee times offer the most comfortable playing conditions.
Common Mistakes to Avoid
Travelers often miscalculate how cold the desert gets once night falls. Here are a few mistakes to sidestep:
- Forgetting a heavy jacket: Assuming Arizona is always hot leads to shivering through outdoor dinners. Always pack a wind-resistant coat.
- Skipping hydration: Dehydration happens just as easily in winter because the air is exceptionally dry. Drink plenty of water throughout the day.
- Ignoring early sunsets: Darkness falls quickly around 5:30 PM. Plan your outdoor photography and trail returns before twilight sets in.
Frequently Asked Questions
Can you swim in outdoor pools in December?
Most standard outdoor pools are unheated and will feel too cold for comfortable swimming, with water temperatures dropping significantly. However, many resorts and hotels maintain heated pools and hot tubs specifically for winter guests.
Does it ever snow in Phoenix in December?
Snow in the city proper is virtually unheard of. While surrounding high-elevation areas like Flagstaff receive heavy winter snow, Phoenix stays warm enough that precipitation falls entirely as rain.
How crowded is Phoenix during December?
December is a popular tourism month, particularly around the Christmas and New Year holidays. Snowbirds and holiday travelers fill hotels, restaurants, and golf courses, so expect higher demand and book reservations early.
Do I need a rental car to get around?
While downtown Phoenix features light rail transit, the metropolitan area is sprawling. Renting a car gives you the flexibility to visit neighboring Scottsdale, Tempe, and remote trailheads efficiently.
