Inch by inch by inch, weekend rain heals drought wounds. That is, it is healing the landscape across the El Dorado County and Northern California, squelching the danger of wildfires, filling Folsom Lake up by several feet, and putting Tahoe winter sports back on the map for the coming Presidents Day weekend.
At North Tahoe, Squaw Valley USA closed for the day. An hour south of Lake Tahoe near Carson Pass, so did Kirkwood. On Sunday, Squaw reported 38 inches of fresh powder in a 24-hour period on its upper mountain. Kirkwood reported 67 inches on top for the five-day storm. Squaw and Kirkwood have areas with localized microclimates where specific bowls and slopes act as snow scoops.
Lake Tahoe itself had received 13.5 billion gallons of water in a 24-hour period that ended Sunday morning
Many areas across the county have received about six inches of rain during the storm series. In a drought, the first three inches is absorbed as if landing on a giant dry sponge. Runoff is minimal, but will give rise to fresh vegetation. The transformation of of the rolling foothills from brown to green, for instance, will be sensational in the next month.
Some areas, though, really got hammered. Bald Mtn gauge near Georgetown, recorded almost 8 inches of precipitation for a 24-hour period and more than 12 inches since the storm started. Areas from El Dorado Hills to Cameron Park received over 3 inches of precipitation for a 24-hour period. Areas from Cameron Park to Placerville were seeing 4-6 inches of precipitation for a 24-hour period and the Georgetown Divide was getting 6-8 inches of precipitation for a 24-hour period during the height of the storm.
About noon Sunday, S.p. wrote, "6.20 " from 5 am Saturday to 5 am Sunday in Pollock Pines. EL5500"
About 1pm Sunday, Karyn wrote, "Our rain gauge is indicating 9.91 inches since Friday morning. We are in Pollock at about 4100' elevation."
About 2pm Sunday, Karen wrote, "7.6 at my place in Pleasant Valley since Fri morning"
About 3pm Sunday, Mike wrote, "I should have emptied my gauge last night. I woke up here in CP to it overflowing at 5" and don't know how much I missed but it's already got another .75" in it.'
About 5pm Sunday, Sal wrote, "I have gotten enough to fill this water bath canner, about 8 inches"
About 5pm Sunday, Lindsey wrote, "last check is around 10" in somerset"
As,of 6pm Sunday, Mike wrote, "the water level at Folsom Lake has risen 9.5 vertical feet since the rain started and even though the rain has essentially been over for a few hours, water inflow amounts are still increasing every hour."
The official record for Pilot Hill (between Cameron Park and Coloma) marked 3.35 inches on Sunday, and 5.47 inches for Thu, Fri, and Sat, bringing the storm total to 9.82 inches and a seasonal total of 13.34 inches of precipitation.
That's how nature heals the land.
Drought is Not Over.
You may hear reports that say, "The storm hasn't really put a dent in the drought." What this means is, "The levels at reservoirs for water to be sent south have not come up."
(KCRA) —Folsom Lake continues to rise as creeks and rivers flowing into the reservoir surge with runoff after days of rainfall. Since the start of the storm Friday, the lake has risen 14 feet, according to data from the California Department of Water Resources.
When the ground is saturated, the runoff starts from rain, as well as from snowmelt in late spring, of course. As of Sunday, most reservoirs had not risen at all. As of one week ago Sunday, Folsom Lake had only 17 percent of its total capacity. The recent rains added 30,000 acre-feet by early Sunday and pushed it to just 20 percent of capacity – still barely one-third of what it should be for this time of year. The low reservoir levels stood in contrast to heavy precipitation, particularly in foothill areas, since the storm began Wednesday night. By Sunday afternoon, Grass Valley had reported 101/2 inches of total rain, Auburn Dam Ridge nearly 71/2 inches, Placerville nearly 7 inches.
Over the four-day period, the lake added roughly 54,000 acre-feet of water, nearly a quarter of the lake's current content.
Wayne Lusvardi writes:
In California, drought is normal. What California depends on is a wave of monsoon rainstorms in a single year occurring every three to five years to fill reservoirs. When weather conditions result in a skipping of one cycle of monsoon rainstorms, the result in an official drought emergency.
To begin with, an untimely high-pressure “ridge” in the Pacific Ocean about four miles high and 2,000 miles long has caused a three-year drought. As National Geographic described it, “Storms that would normally soak a parched state — and build up California’s snowpack — are bouncing off the dome of high pressure, heading into southern Canada, then riding the jet stream south into the U.S. midwest.” This high-pressure ridge has diverted the monsoon rainstorms that California depends on for snowpack in the Sierra Mountain Range that fills water reservoirs.
The storms that finally bought Northern California a desperately needed deepdrenching this weekend after the driest year in state history are the result of a developing situation that scientists call "an atmospheric river," and recent research has shown that they have played a significant role in breaking droughts in the past.
Sometimes known as "the Pineapple Express," these rivers of rain are long, narrow bands of highly-concentrated moisture that are formed in the Pacific Ocean and barrel eastward until they hit land, bringing downpours and flooding. When they hit California, they pack an amazing punch. Just one can carry 15 times as much water as the Mississippi River.
The term "atmospheric river" was coined just 15 years ago, when new technology allowed scientists to put microwave equipment on satellites that better measured water vapor patterns in the air.
Since then, scientists have come to realize that such systems transport huge amounts of water in warm, moist air like conveyor belts to California. Even though they are only a few hundred miles wide, a few such storms often provide the bulk of the state's annual water and snow.
Atmospheric rivers are responsible for nearly 50 percent of all the precipitation on the West Coast. They have been the cause of historic storms, Dettinger's research shows, from the 1861 floods that forced Gov. Leland Stanford to take a row boat through the streets of Sacramento to his inauguration to the downpours of 1997-98, which flooded Yosemite Valley.
Unfortunately, this weekend's atmospheric river doesn't make future storms more likely. But it does show that the stubborn ridge of high pressure off the West Coast that has blocked storms for more than a year can break down, said Daniel Swain, a Ph.D. candidate at Stanford University who closely studies the subject.
"There's no guarantee that it won't come back," Swain said of the ridge. "It's possible this is just a temporary break, but I'm cautiously optimistic we'll have more typical rainfall conditions for the rest of the winter."