Snow falling in the mountains and valleys was a welcome sight in a state struggling with drought.

Heavy late-December snowstorms made that month the wettest it has been in at least two years, and snowfall from the more recent storms seems to be breaking La Niña’s dry winter curse. But experts caution the somewhat-promising start to winter is just that — a start.

It’s too soon to know whether the spate of precipitation will be fleeting or will multiply into more storms, building the snowpack needed for a healthy spring runoff to feed rivers and defying La Niña, a weather pattern that typically makes the Southwest drier than normal in the winter and spring.