'Extreme' drought nearly eliminated in California in wake of storms caused by atmospheric rivers

"Extreme" drought, the second-highest level of drought, has been nearly eliminated in California in the wake of storms caused by atmospheric rivers slamming the state over the last several weeks.

Extreme drought fell from 27.1% last week to 0.32% in the numbers released Thursday, according to the U.S. Drought Monitor. "Severe" drought, the third-highest level, fell from 71% to 46%.

Parts of California have received more than 3 feet of rain since Christmas, while the Sierra Nevada Mountains have had a record snowiest start to the season, already surpassing seasonal averages.

California drought map

The data includes rain collected through Jan. 9 at 4 a.m., while doesn't include the last two days of heavy rain.

It will take several seasons at 120% to 200% the normal rain and snowfall to eliminate drought in the West, according to experts. However, the Sierra Nevada region is already measuring between 87% and 192% of its normal precipitation for the season.

The rain is helpful, but snowpack is even more critical -- even preferable -- because it melts slowly and is better absorbed by the ground and also later contributes to the "water bank" for the spring and summer, Nate Stephenson, a scientist emeritus at the U.S. Geological Survey's Western Ecological Research Center, told ABC News.

California is currently at 226% of its normal snowpack for this time of year has surpassed the normal amount that is measured on April 1, when the snowpack is typically at its peak.

Soil moisture in California has also drastically improved -- measuring at 100% as of Tuesday, compared to 2% on Nov. 1. The moisture is likely staving off a mass die-off of trees in the state, experts told ABC News.

Some of the largest reservoirs in California are also beginning to recover, but they remain nowhere near their typical average for this time of year.

After years of drought, here's a look at how this winter's storms help the state's water supply.

Shasta Lake, located in Shasta County in Northern California, is currently at 41% capacity versus an average of 67% for this time of year.

Lake Oroville and Folsom Lake are currently at 46% and 42% capacity, respectively, compared to average storage capacities of 85% and 100% for this time of year, data shows.

The inundation so far is not helping the Colorado River Basin as much, the region that needs the most help -- including Lake Mead and Lake Powell -- because they are in the heart of a 22-year mega drought.

Lake Mead is at 28% capacity after hitting record lows last summer.

ABC News contributed to this report.