It’s raining in Arizona right now mainly because a couple of winter weather systems are passing over the Southwest, pulling in moisture and lifting it over the state, which produces clouds and showers instead of the usual dry sunshine.

Quick Scoop

1. The simple answer

For late January 2026, forecasters say a low‑pressure system and related disturbances are moving in from the Pacific and the north, bringing cooler air and enough moisture to trigger rain and some high‑elevation snow across much of Arizona. This setup is pretty normal for mid‑winter, even if it feels strange compared to the state’s long, hot dry stretches.

2. What’s happening in the atmosphere?

  • A low‑pressure system off the California coast is sliding into the Southwest, which encourages rising air and cloud formation over Arizona.
  • Disturbances in the jet stream are passing through, giving multiple waves of lift that support rounds of showers rather than just one quick burst.
  • At the same time, cooler air is dropping in from the north and mingling with the Pacific moisture, which helps turn some of that rain into snow in the higher terrain.

Think of it like this: instead of the usual “dome” of dry, sinking air over the desert, the lid is off for a few days, so air can rise, condense, and fall back down as rain.

3. What it means on the ground

  • Phoenix and the lower deserts are seeing light, on‑and‑off showers with modest totals (a few tenths of an inch in many spots).
  • Southeast Arizona, including around Tucson, has higher odds of getting steadier or longer‑lasting rain, with somewhat larger totals and water pooling on roads and in normally dry washes.
  • Northern and eastern high country areas are picking up rain changing to snow, with several inches possible at higher elevations and some travel impacts on mountain highways.

4. “But isn’t Arizona supposed to be dry?”

Arizona is usually dry because high pressure and desert geography limit how often strong, moist systems reach the state, but “dry” doesn’t mean “no rain,” especially in winter. Winter is one of the two wet seasons (the other is monsoon in summer), and every year a few Pacific or mixed systems bring rain and mountain snow that recharge soils, rivers, and reservoirs. So the rain you’re seeing now is less a freak event and more one of those periodic, much‑needed visits from a passing storm.

TL;DR: It’s raining in Arizona because winter storm systems—driven by low pressure, Pacific moisture, and cooler air—are moving through, making conditions temporarily cool and unsettled instead of hot and dry.

Information gathered from public forums or data available on the internet and portrayed here.