December weather Phoenix Arizona offers a stark contrast to the freezing winters found across much of North America. Daytime high temperatures hover comfortably in the mid-60s to low 70s Fahrenheit (roughly 18°C to 22°C), while overnight lows drop into the crisp 40s (4°C to 9°C). Rainfall remains minimal, averaging around one inch for the entire month, and the region basks in roughly eight hours of daily sunshine. This dry, mild climate makes December one of the absolute best times of the year to explore the Sonoran Desert without battling extreme heat or humidity.
Understanding this climate means knowing how to pack and plan. While afternoons feel warm enough for t-shirts during outdoor hikes, temperatures plummet quickly once the sun sets behind the mountains. Packing in layers isn't just a suggestion; it's essential for anyone spending full days outdoors. From holiday light displays at local resorts to traffic patterns and packing tips, this guide breaks down everything you need to know about experiencing the desert during the final month of the year.
Temperature Breakdowns and Daily Patterns
Average high temperatures start the month right around 70°F (21°C) and slowly slide down to about 65°F (18°C) by Christmas week. Mornings are brisk, often starting near 45°F (7°C). Frost is rare within the urban core, though outlying desert valleys occasionally dip lower.
The air is exceptionally dry. Unlike humid winter destinations where cold dampness cuts to the bone, dry desert air feels refreshing. When you're walking under direct sunlight, it often feels 5 to 10 degrees warmer than the official thermometer reading. However, the moment you step into the shade or the sun goes down, the temperature drop is immediate.
- Daytime (10:00 AM – 4:00 PM): Warm, sunny, ideal for hiking, golf, and patio dining.
- Evening (5:00 PM – 9:00 PM): Cool, requiring a light jacket, sweater, or fleece.
- Night (10:00 PM – 6:00 AM): Cold enough to warrant heating in homes or heavy blankets if you're camping.
What to Pack for a December Trip
Packing for Phoenix in December trips up many first-time visitors who assume "Arizona" automatically means relentless heat. Because of the 30-degree swing between day and night, your suitcase needs versatility.
- Layering Essentials: Bring breathable short-sleeve shirts or light long-sleeve tops for the day, paired with cardigans, hoodies, or fleece jackets for the evenings.
- Outerwear: A windbreaker or medium-weight coat is necessary for night walks, stargazing, or early morning desert tours.
- Footwear: Sturdy trail shoes or hiking boots if you plan to hit the local mountains, plus casual shoes for city walking.
- Sun Protection: Sunglasses, sunscreen, and a hat are just as important in December as they are in June. The winter sun sits lower in the sky but can still cause sunburns during long hikes.
Outdoor Recreation and Peak Season Realities
Because the weather is so inviting, December marks the beginning of peak tourism season in the Valley of the Sun. Popular trailheads at Camelback Mountain, Piestewa Peak, and the McDowell Sonoran Preserve fill up by 8:00 AM on weekends. If you want a parking spot and quieter trails, plan your outdoor excursions for dawn or late afternoon.
Golf courses operate at high capacity throughout the month. Greens are overseeded with winter rye grass, keeping courses lush and green, but tee times book out weeks in advance. Booking early saves both money and scheduling headaches.
Common Mistakes to Avoid
- Underestimating the evening chill: Don't leave your hotel without a jacket expecting daytime warmth to linger past 5:00 PM.
- Skipping hydration: Because the air is dry and cool, you won't feel as thirsty as you would in summer, but dehydration happens just as fast on desert trails.
- Ignoring holiday traffic: Major seasonal events, such as the holiday light displays at the Fairmont Scottsdale Princess or the Phoenix Zoo Lights, draw heavy evening traffic to local corridors.
Frequently Asked Questions
Can you swim in Phoenix hotel pools in December?
Most standard outdoor hotel pools are unheated and will feel too cold for comfortable swimming, with water temperatures hovering in the 50s. However, many upscale resorts and spas maintain heated pools and hot tubs specifically for winter guests.
Does it ever snow in Phoenix in December?
Snow in the city proper is extraordinarily rare. While surrounding high-elevation areas like Flagstaff or Payson receive heavy winter snowfalls, Phoenix experiences rain showers rather than snowstorms when winter weather systems pass through.
How crowded are tourist attractions in December?
December is a busy travel month, especially during the weeks leading up to Christmas and New Year's Eve. Expect larger crowds at major attractions, popular restaurants, and hiking spots, alongside higher rates for rental cars and accommodations.
Is December windy in Phoenix?
Winter weather systems can occasionally bring breezy days, but high winds are uncommon. Most days feature calm winds and clear, blue skies, making it ideal for outdoor photography and sightseeing.
