Warming winter, low rainfall raise fears of more drought
CHICO » High temperatures combined with low precipitation make for concern for the rainy season, as much of California remains well below needed snowpack levels for a second consecutive year.
The National Weather Service in Sacramento reported high temperatures which were seen starting last Saturday will persist through this weekend. The recent days of high winds created additional problems, further drying out already dry grasses and trees.
Meteorologist Hannah Chandler-Cooley said recently that generally, normal maximum temperatures in the Sacramento Valley in January are in the low to mid50s.
Starting Saturday, temperatures measured at highs in the early 70s, cooling only slightly into the upper 60s by Tuesday. These rates exceeded seasonal yearly averages by 15 to 20 degrees.
Chandler-Cooley said there isn’t necessarily reason to be concerned.
“It’s not necessarily unheard of to have these warm spells during the wet season,” she said, and added the trend won’t last long.
While the entire state is below normal ranges for rainfall, half of January and February still remain possible for precipitation to help improve water levels.
However, California Department of Water Resources’s information officer Chris Orrock said, “We are very dry. We’re looking at about being in the bottom 10 driest periods on record for the state.”
The overall statewide water and snowpack levels are at 42% of average, largely driven down by the southern part of the state sitting at 23% of average. The north state is at 50% of average for snowpack, while the central state is at 45%.
While several “good storms” took place in November and December, Orrock said because they were largely isolated in the north state, overall snowpack is very low due to ongoing drought in particularly the southern and central portions of the state.
There is some time to make up some of the drought, he added. But, “We are coming into what
looks like the second of two dry years.”
La Niña weather conditions are also being seen, which leads to below-average precipitation and higher temperatures, and meteorologists are not seeing any large storm indicators to impact California in the next several weeks, Orrock said. A high-pressure system sitting off the Pacific coast is currently moving any approaching storms away from the state, a phenomenon he said has been common since the droughts of 2011 and 2016.
“If it moves just a bit … atmospheric rivers could make up the deficit we’ve seen so far,” he said. “But the longer we go … all the more has to be made up.”
Another problem during such dry periods is the potential for environmental damage and fire starts when accompanied by high winds like those seen since Saturday. High wind speeds which knocked down some trees and power lines across some areas of Northern California.
“In burn scar areas damaged by drought, the high winds cause downed trees and power lines. A lot of trees are already weakened,” Chandler-Cooley said.
These wind speeds and dry vegetation were also connected to unusual fire starts for January seen in some areas like Santa Cruz and San Mateo counties, where at least a dozen fires were being fought as of Tuesday, some of them rekindled from still-hot embers of fires months ago.
Another side effect of the wet year has been low water levels in water reservoirs across the state.
Oroville’s Department of Water Resources Public Information Officer Liza Whitmore reported Lake Oroville is one of those reservoirs, currently measuring at 695.40 feet elevation, or 55% of the average water level.
“A full reservoir will reach nearly 900 feet elevation,” Whitmore noted.
“State Water Project operators have been decreasing outflows from Lake Oroville to conserve storage,” she added. “The low flow channel of the Feather River, near the Feather River Fish Hatchery and through Oroville, is kept at 800 cubic feet per second to maintain safe levels for fish such as salmon and steelhead.”
She added rice farmers in the Sacramento Valley have already obtained much of their water used for rice stubble decomposition for this season.
“Low lake levels at Lake Oroville have put several boat launch ramps out of the water with only Bidwell Canyon’s ramps and a temporary ramp at the Spillway available for use,” Whitmore reported. “Less water in area rivers can affect habitat through less wetland flooding, less groundwater recharge, higher mortality on young fish and other ecological impacts.”
Whitmore added, “When it comes to water conservation no action is too small, and it is important for Californians to consider every drop of water that they use.”
There is possible relief forecast in the coming week, as a high-pressure system could bring the potential for low precipitation or up to ¼ of an inch of rain to parts of Northern California, but it may not be much.