Years of drought have been wiped out by an active storm track in California this winter, and drought conditions have dramatically improved across the West. Furthermore, this trend is expected to persist into the spring.
A dominant weather pattern featuring a southward dip in the jet stream over the West has allowed a series of precipitation-rich storm systems to track through the region, especially over the last two months.
Far-above-average rain and snow over the last few months have knocked out the years-long drought in California.
This drought reduction was largely due to a very wet period that lasted from early February into early March.
San Francisco, Sacramento and Reno recorded double the average precipitation in the period from early February into early March.
The West Coast has dried out a little in recent weeks, which has allowed for more sunshine and a super bloom of wildflowers in Southern California.
This pattern has also brought colder-than-average temperatures to much of the West, helping to turn wet systems into snowy ones. Seattle had its third-coldest February on record, and Missoula, Montana, had its second-coldest February. The chilly conditions have extended farther south, as evidenced by the fact that Santa Barbara saw its third-coldest February.
Snowier systems are a big change from the 2016-17 water year and several years before. Even though it also experienced above-average precipitation, the snowpack in the lower elevations is much higher this water year than last.
Spring and summer snowmelt is crucial to the water supply in the region, so snowpack in the mountains is important for alleviating drought.
As of March 14, the average snow water equivalent in the Sierra is at 159 percent to average for the date – great news heading into spring.
In fact, much of the West is near- or above-average in terms of the snow water content in the snowpack, with a few areas well above 100 percent to average. The far northern Rockies and northern Cascades are notable exceptions.
The most recent data from the U.S. Drought Monitor shows the big changes these storms have brought to the rest of the West.
Just over half of the West was experiencing drought conditions on Jan. 15, but by March 5, barely 25 percent of the region was still in drought.
Additional weak low-pressure systems are expected to impact the West over the next couple of weeks. Each of these will bring additional precipitation to alleviate drought conditions in parts of the region.
The lack of major storm systems might actually be a good thing.
No major flood concerns across California or the West are expected any time soon.