Is the Western drought finally ending? That depends on where you look

Right now, there’s a below-normal likelihood of big fires in the Southwest for early spring due to lots of soil moisture and snowpack.

In the higher-elevation mountains and forests, the above-average snowpack is likely to last longer than it has in recent years, so those regions will likely have a later start to the fire season. But lower elevations, like the Great Basin’s shrub- and grassland-dominated ecosystem, could see fire danger starting earlier in the year if the land dries out.

By a lot of atmospheric measures, California appears to be coming out of drought, and the drought feels like it’s ending elsewhere. But it’s hard to say when exactly the drought is over. Studies suggest the West’s hydroclimate is becoming more variable in its swings from drought to deluge.

Drought is also hard to forecast, particularly long term. Researchers can get a pretty good sense of conditions one month out, but the chaotic nature of the atmosphere and weather make longer-range outlooks less reliable.

We saw that this year. The initial forecast was for a dry winter 2023 in much of the West. But in California, Arizona and New Mexico, the opposite happened.

Seasonal forecasts tend to rely heavily on whether it’s an El Niño or La Niña year, involving sea surface temperatures in the tropical Pacific that can affect the jet stream and atmospheric conditions around the world. During La Niña – the pattern we saw from 2020 until March 2023 – the Southwest tends to be drier and the Pacific Northwest wetter.

But that pattern doesn’t always set up in exactly the same way and in the same place, as we saw this year.

There is a lot more going on in the atmosphere and the oceans on a short-term scale that can dominate the La Niña pattern. This year’s series of atmospheric rivers has been one example.

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Dan McEvoy does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.