By JP Crumrine
Correspondent
Last month, Warning Coordination Meteorologist Alex Tardy of the San Diego Office of the National Weather Service (NWS), was in Idyllwild at the invitation of Mountain Disaster Preparedness.
Tardy spoke in general about weather forecasting and specifically about the coming winter predictions.
“We can predict well in 6 to 10 days pretty accurately,” Tardy said with pride, then lamented that longer range forecasts were less reliable because the presence of many conditions that create and change weather are not yet present and known.
The lower reliability of long-term forecasts was apparent last week. In his Dec. 6, video, Tardy said, “There are some indications that January will be wet but not February.” And this precipitation wouldn’t arrive until the holidays.
However, two days later, Daniel Swain, meteorologist and climate scientist at the Institute of the Environment and Sustainability at the University of California, Los Angeles, shared a slightly different view and confidence about the approaching winter weather.
For the next two weeks, they both agreed. “It will remain dry and warm for the next few weeks,” Swain began, then added, “I expect [it] to change rather dramatically and quickly … I think it will get a lot wetter in the months to come.”
The difference in the confidence of their views for the future was Swain had the benefit of an analysis that aggregated several weather models. The summary indicates that a very strong jet stream will develop south of Japan in the next two weeks and move east across the Pacific Ocean.
This, in combination with the El Niño conditions in the equatorial Pacific, is likely to bring several Pineapple Express storms to Southern California because these combined pattern changes are more likely to bring the jet stream further south.
Is a stormy and wet January a guarantee? Not yet, according to both meteorologists.
In his blog, Swain wrote, “… the critical time for California remains about 2 weeks out, then the nose of this powerful jet core would possibly arrive near the coast. Will it make it all the way, and will it still be remarkably strong? Will it direct a sequence of strong/moist storms into California in the days following? I’m leaning toward yes at the moment, but as always … things can change, and this is still a fair distance in the future. Uncertainty is high, but this certainly has potential.”
Recent El Niño weather conditions have not produced very rainy winters. In fact, the two most recent wet winters, including 2023, were when La Niña conditions were present.
This year, the NWS sees a very strong El Niño in the Pacific now.
While Tardy leans toward more precipitation next month and during winter, he did not have the benefit of Swain’s more recent analysis.
“I have high confidence in a wetter winter than not. December was distinctly different than January through March will be,” Swain concluded in his broadcast.
But both men cautioned about this year’s snowpack. With an expectation of a warmer than normal winter, even with greater precipitation, it is more likely to rain. And the warmer temperatures will prevent the ground from getting cold enough to prevent whatever snow may fall from accumulating.
