You’re probably checking the weather because you’re tired of the gray or maybe you're planning a quick hike up Tumamoc Hill. Honestly, everyone thinks Arizona is just a giant blast furnace 365 days a year. It’s a common mistake. But if you’re looking at the tucson 20 day forecast right now, you’ll see the Sonoran Desert is actually pulling its winter weight.
It’s currently 46°F out there tonight. Crystal clear skies. A tiny 1 mph breeze from the east is barely moving the air. Basically, it’s perfect jacket weather if you’re heading out for a late-night taco run.
What’s Actually Happening Over the Next Week?
The next few days are looking pretty sweet. Saturday, January 17, is going to be a bright one with a high of 73°F. You’ve got clear skies and a very manageable 23% humidity. It’s that dry heat people joke about, but in January, it’s just comfortable.
Sunday gets even warmer. We’re looking at 74°F for the high, though it might get a little "partly sunny" with a 10% chance of rain. Don't go canceling your brunch plans, though—10% in Tucson usually means you might see a cloud that looks like a rain cloud, and that's about it.
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By Monday and Tuesday, things stay consistent. Highs around 72°F or 73°F and lows dipping into the mid-40s. It’s a classic desert swing. You start the day in a hoodie and end it in a T-shirt.
The Mid-Forecast Shift
Things get interesting around Friday, January 23. The tucson 20 day forecast shows a bit of a mood swing. We’re looking at a 35% chance of light rain during the day, which jumps up to a 75% chance of showers by Friday night.
Saturday, January 24, looks like the wettest day of the bunch.
- High Temperature: 65°F
- Chance of Rain: 75%
- Wind: Southeast at 3 mph
- Humidity: Jumping up to 48%
If you’re a local, you know we actually celebrate the rain here. The smell of creosote after a desert shower is better than any candle you can buy at the mall.
Looking Into Late January and Beyond
Once that rain clears out, Sunday, January 25, brings back the sun with a high of 68°F. By Monday, January 26, we’re back up to 73°F. This is the "Goldilocks" zone of Tucson weather. Not too hot, not too cold. Just right for basically anything outdoors.
Looking further out toward the end of the month, the historical trends suggest we’ll stay in that 60°F to 70°F range for highs. Nighttime is where you have to be careful. Lows will consistently hover between 44°F and 50°F. If you're camping in the Catalina Mountains, expect it to be way colder than the city center.
Real Talk on Desert Layers
You’ve gotta dress like an onion. Seriously.
- The Base: A breathable T-shirt for that 2 PM sun.
- The Middle: A light flannel or long-sleeve.
- The Outer: A decent windbreaker or light jacket for when the sun drops behind the mountains at 5:45 PM.
The temperature drop-off once the sun goes down is no joke. It can feel like a 30-degree difference in what feels like thirty minutes.
Actionable Tips for the Next 20 Days
If you're following the tucson 20 day forecast to plan your life, keep these things in mind.
- Watch the UV Index: Even when it’s 70°F, the UV index is still hitting around a 3. It’s enough to catch a burn if you’re out on a long trail like Seven Falls without sunscreen.
- Humidity is Low: 20% to 25% humidity means you’re losing moisture faster than you realize. Drink more water than you think you need.
- Plan for the 23rd: If you have outdoor events, Friday and Saturday (Jan 23-24) are your high-risk days for rain. Have a backup plan or a really good umbrella.
- Check the Wind: Most days are calm (around 2–5 mph), but Tuesday, Jan 20, might see gusts up to 7 mph. Not a windstorm, but enough to blow your hat off if you're not careful.
The desert in January is easily one of the best places to be. Enjoy the sun while it's mild, and maybe keep a light rain jacket in the trunk for that late-month shower.