Southwest Colorado got hit by a warm winter system, sometimes called a Pineapple Express, Saturday night, and the region can expect a string of storms one after another through the week.

A system moving in late Wednesday is expected to be colder than the two cells ahead of it, said Chris Cuoco, a meteorologist with the National Weather Service in Grand Junction.

“You got a warm subtropical system that started in the Pacific around Hawaii on Saturday night, and it never really dries out this week,” he said.

Monday may be the clearest day of the week, Cuoco said, but even Monday a chance of a rain-snow mix below 7,500 feet and snow above 8,500 feet remains in the forecast.

Late Monday night, another system should move into Southwest Colorado and the Four Corners. Cuoco said it too will bring winds from the southwest, and is not expected to lower temperatures significantly. Cuoco expects more of a rain-snow mix from this cell as well.

The cell that moves in late Wednesday and early Thursday, Cuoco said should be colder and produce more snow, but even then he said lower elevations of Southwest Colorado, like Cortez, should see highs in the mid-30s.

“We’re riding on a glide path with storm after storm lined up for the next week or so,” he said. “All the storms should produce good snowfall in the higher elevations of the San Juans.”

On Sunday, a winter storm warning was in effect for the San Juan Mountains for elevations above 8,000 feet through 6 p.m. A winter storm warning means the weather service expects snow will make travel hazardous or impossible over mountain passes.

“This is not the day to be going over Coal Bank or Lizard Head,” Cuoco said.

Chains or snow tires were required on Coal Bank and Molas Pass Sunday afternoon.

As of Sunday afternoon Purgatory Resort reported 1 inch of new snow in the last 24 hours. Telluride Ski Resort reported 2 inches and Wolf Creek Ski Area reported 2 inches.

The Colorado Avalanche Information Center lists the avalanche danger as considerable, or a 3 on its 5-point scale with 5 being extreme.

The Pineapple Express that moved through Saturday night and early Sunday morning gets its name from the area where it forms, near the Hawaiian islands.

Cuoco said a wet heavy snow fell in the mountains below 8,500 feet on Saturday night and Sunday morning.

The weather service is expecting an El Niño this winter, but so far the weather service has issued only an El Niño watch, and has not officially declared an El Niño, Cuoco said.