Whether precipitation and temperatures end up above or below normal here this year, forecasters say it’ll  be about a 50/50 shot revolving around a La Nina event.

“We are likely going to shift into a La Nina winter, which means sea-surface conditions are going to be favoring colder-than-normal temperatures which tends to influence weather patterns across the globe,” Sam Webber, meteorologist with the National Weather Service’s Salt Lake City office, told the Standard-Examiner Monday. “In North America, we see trends across the the Western United States that favor above-normal precipitation during La Nina years in the Pacific Northwest and below-normal precipitation in the Southwestern U.S.”

Caught in the middle of this is Utah.

“In typical La Nina winters, northern Utah — especially far northern Utah — tends to side a little bit better with the Pacific Northwest region, whereas the southern half of Utah sides better with the Southwest as far as seasonal predictability goes,” Webber said.

He said the most recent outlooks for the winter months predict equal chances for above- or below-normal precipitation for the northern 2/3 of the state while the southern 1/3 of the state favors below-normal precipitation.

Webber said La Nina patterns like what is predicted can see a lot of variance in the region.

“This event is currently forecast to be a weak La Nina event,” he said. “Since 1990, we’ve had seven weak La Nina events. If we take a look locally, say in Upper Cottonwood Canyon, four out of those seven winters where we had weak La Ninas ended up drier-than-normal and then three out of the seven ended up wetter than normal.”

He noted that one of those weaker La Ninas was two seasons ago when the Wasatch Front saw record snowpacks.

“It’s still looking like we’re going to be kind of equal chances,” he said. “Really, that’s kind of what we were in our blockbuster winter of ’22-’23 where we were in a weak La Nina, similar to what we are going into this year, and we saw an incredible season. Year before that, the ’21-’22 season, was also a weak La Nina, the year before that was a moderate La Nina and those were all varying intensities of winter.”

As for the lower elevations, he added that what type of precipitation is seen under this pattern can depend a lot on where the storms originate.

“If we have storms moving in from the south or southwest as we do coming up this week, it’s going to be much warmer and favor higher snow levels so the valleys are going to see much more rain,” he said. “If we see a storm coming from the northwest or north, that sees a lot colder air, we’re going to see more potential for snow.”

Webber said that, with the snow season really just getting under way, snowpack numbers are just a bit below average.

“We like to take a look at, especially in northern Utah, Upper Little Cottonwood Canyon at the snow and snow-water equivalent accumulated through the season up there,” he said. “The average peak in that snow-water equivalent through all winters is 48.6 inches. As it stands right now, we’ve only seen 3 inches of snow-water equivalent. … We’re sitting at 2.3 inches of snow-water equivalent where we should be around 4.8 (inches). We’re a little bit below, we’re about 50% of normal right now, so we’re really going to need to start turning on the faucet, per se, to get the snow-water equivalent numbers up through the rest of the winter.”

He noted that peak snow-water equivalent in the region usually isn’t reached until late April, so there are abundant chances for the state to catch up on precipitation.

“So far, things are shaping up pretty good,” he said. “I suspect that this storm that we’re about to get (is) going to bring the Northern Utah mountains upwards of 1-2 inches of snow-water equivalent. That’s going to bring a pretty big bump in our season snowpack and snow-water equivalent accumulation. We’re going to shut off for a period thereafter where we might see some dry weather, but it’s still early in the season and, really, we’re just going to have to take a pulse check as we head into the beginning of the new year.”