<body><div><figure><img src="https://img.particlenews.com/image.php?type=thumbnail_580x000&amp;url=1skfZK_1H3dAdMz00" alt="https://img.particlenews.com/image.php?url=1skfZK_1H3dAdMz00" width="1600" height="900" ><figcaption>The latest forecast for rain and snow across northern California. Graphic courtesy National Weather Service, Sacramento</figcaption></figure>A series of Pacific storms is expected to reach Plumas County starting Friday, bringing rain, gusty winds and a chance of thunderstorms before colder weather introduces some snow. Local and state agencies are watching roads and slopes across the Dixie Fire footprint.For Quincy specifically, the National Weather Service office in Sacramento forecasts rain Friday with a possible thunderstorm, temperatures around the upper 40s and south-southwest winds that could gust to roughly 40 mph. Rain will continue through the night, with more wet weather through the weekend and rain and snow possible by Monday.As of Wednesday evening, National Weather Service graphics forecast as much as 12 inches of snow above 6,000 feet, with 2 feet at highest peaks and an inch or less down to 5,000 feet.Forecasters currently do not expect a widespread flash-flood problem, based partly on a relatively dry start to the water year leaving soil unsaturated. In an email statement Monday, NWS told The Plumas Sun flooding impacts were unlikely and the agency did not expect the intense rainfall rates associated with thunderstorms at this time.The approaching storms will reach a landscape that agencies now classify differently than they did in the years immediately after Dixie. From 2022 to 2025, the hydrophobic soil and loss of vegetation made the region especially susceptible to erosion, mudslides or flash floods. The fire was recently removed from the NWS public burn scar rainfall threshold page. The NWS Sacramento office said “it was retired from their burn scar-specific flash flood warnings because the burn scar is five years old and enough recovery has been observed to limit overall concerns.” That change does not mean mud, rocks or sediment will no longer move during storms.<figure><img src="https://img.particlenews.com/image.php?type=thumbnail_580x000&amp;url=2mzi2P_1H3dAdMz00" alt="https://img.particlenews.com/image.php?url=2mzi2P_1H3dAdMz00" width="1600" height="900" ><figcaption>Latest precipitation forecast. Graphic courtesy National Weather Service, Sacramento</figcaption></figure>“We generally retire thresholds when we don’t anticipate there being a potential for damaging debris flow events,” said Don Lindsay, program manager for the California Geological Survey’s Burned Watershed Geohazards office.In other words, “retired” doesn’t mean nothing can happen. It means the risk of the large, damaging debris flows that prompted special warnings after the fire has declined. The agency added that it would still issue regular flash flood warnings should a thunderstorm or atmospheric river produce heavy enough rain.County agencies preparePlumas County emergency officials have been preparing for winter weather since September, said Lori Pini, manager of the county office of emergency services.OES has participated in briefings with state officials at the California Governor’s Office of Emergency Services and NWS. Pini has also surveyed local fire departments about their need for sand and sandbags, and she contacted community services districts about their ability to operate during significant weather and power outages.The county also held a pre-El Niño meeting Oct. 15, attended by 34 representatives from 24 partner agencies, including the sheriff’s office, California Highway Patrol, the California Department of Forestry and Fire Protection, local fire departments, public works, Plumas National Forest and emergency medical and public health agencies.Pini said the county has identified locations that have flooded previously and plans to monitor them as the storms arrive. Public works officials also continue to watch locations where problems have occurred within the Dixie Fire burn area.If conditions worsen, OES can increase the frequency of agency briefings, said Pini. Emergency notifications or evacuations, if needed, would be coordinated with the sheriff’s office through the Genasys alert system.Pini said OES does not receive current slope-stability assessments. Understanding how the landscape itself has changed since Dixie falls largely to scientists such as those at the California Geological Survey.Measuring recovery after DixieFollowing the fire, Lindsay said CGS and its partners established an “unusually” extensive monitoring program to understand how burned slopes responded to rainfall.Each year, scientists reviewed rainfall and runoff data from roughly the previous 12 months. They gathered information from rain and stream gauges, monitored instruments installed on burned slopes, studied satellite measurements of vegetation and repeatedly returned to specific locations to measure vegetation and ground cover.The hydrology changed along with the vegetation. Immediately after a severe fire, rainfall can move rapidly across exposed ground instead of soaking into it. Lindsay said monitoring showed the amount of runoff generated by a given amount of rainfall declined as the landscape recovered.CGS compiled those results and discussed them with NWS and other agencies before recommending whether Dixie-specific rainfall thresholds should remain in place.“I like to think of it as a collaborative decision,” Lindsay said.In addition to ground monitoring, how the Dixie burn scar is recovering can also be measured from space using satellite images.<blockquote>“There’s a fair amount of recovery on the landscape and that recovery can be seen.”Don Lindsay, California Geological Survey’s Burned Watershed Geohazards program manager</blockquote>According to data from the Chambers Creek monitoring site above the State Route 70 corridor, total vegetative ground cover increased from roughly 55% after the fire to about 85% today. Live vegetation reached about 40% by October 2024. At the nearby Chips Creek site, ground cover exceeded 92%, according to CGS.“There’s a fair amount of recovery on the landscape and that recovery can be seen,” Lindsay said.CGS did not treat the nearly million-acre Dixie footprint as a single landscape. Scientists paid particular attention to the steep, wetter Feather River Gorge and Highway 70 corridor. A separate monitoring zone covered the drier eastern and northeastern portion of the fire near Interstate 395. The two areas initially had different rainfall thresholds because their climates, terrain and runoff behavior differed.Recovery does not mean the hazards are goneEven after the special postfire thresholds were retired, Lindsay said the Feather River Canyon remains inherently vulnerable.“The steep slopes are subject to those hazards irrespective of fire,” he said.<figure><img src="https://img.particlenews.com/image.php?type=thumbnail_580x000&amp;url=2mlT2E_1H3dAdMz00" alt="https://img.particlenews.com/image.php?url=2mlT2E_1H3dAdMz00" width="1600" height="1200" ><figcaption>Slide near Rush Creek Road, winter 2023.</figcaption></figure>Dixie increased that vulnerability, particularly in the first years following the fire, but the landscape’s recovery has substantially reduced the additional runoff-driven hazard caused by the burn, Lindsay said. Some effects of a major wildfire, however, can remain much longer.And the type of postfire hazard can change with time. In the first years after a severe fire, intense rainfall hitting exposed slopes can quickly turn into runoff. That water can scour loose sediment and carry rock, soil and woody material downslope as a debris flow.As plants and ground cover return, that immediate runoff response diminishes.But Lindsay said scientists are also studying a later postfire process involving shallow landslides. Several years after a fire, water can again infiltrate soils more readily. At the same time, roots from fire-killed vegetation can decay and lose some of the strength they once provided to the soil.Shallow landslides can become a concern roughly four to seven years after a fire under the right conditions, Lindsay said. Dixie is now five years old.That doesn’t mean scientists expect such landslides from this weekend’s storms. Lindsay emphasized that the later process is considerably more difficult to predict than the rapid debris flows that can follow a newly burned landscape. Soil saturation, drainage between storms, root strength and other factors all play a role.Forecasters have also said soils remain relatively dry entering this week’s storms, one reason widespread flooding isn’t currently anticipated.Not all rain falls the same wayResearch after Dixie has shown why the total amount of rainfall from a storm doesn’t tell the entire story.Lindsay and other researchers studied two very different storms over the burned Feather River Canyon.One delivered a large amount of precipitation over a longer period but at relatively low intensity. Another delivered far less water overall but included a short burst of extremely intense rainfall.It was the short, intense storm that produced major debris flows, including flows that blocked Highway 70 and scoured channels in the Feather River Canyon.Runoff-driven postfire hazards, Lindsay said, are “largely controlled by short duration, high-intensity rainfall.”That difference is important as Friday approaches. NWS now includes a slight change of thunderstorms in the Plumas County forecast Friday afternoon. This doesn’t mean debris flows are expected, but it’s one reason scientists and forecasters pay attention to how quickly rain falls, not simply a storm’s final precipitation totals.Highway 70 remains closely watchedMeanwhile, the California Department of Transportation is monitoring the incoming storms and the impacts of wet weather to local highways.“State Route 70 is always a route to keep an eye on there through the Feather River Canyon,” said Chris Woodward, a spokesperson for Caltrans District 2.Woodward said the concern comes from both the Dixie Fire footprint and the canyon itself. The two-lane highway runs through steep terrain with exposed rock slopes on one side and the Feather River on the other. Rain, erosion and freeze-thaw cycles can contribute to rockfall and slides even without a wildfire.Those hazards have repeatedly affected the highway since Dixie.Woodward pointed to a major slide near the Butte-Plumas county line during an October 2021 atmospheric river as well as debris flows near Opapee and Murphy creeks in June 2022. The June debris flows occurred within the Dixie burn area.Caltrans maintenance crews monitor weather forecasts and locations with histories of problems, said Woodward. Before winter, crews inspect culverts and roadside drainage and address vegetation hazards. Crews can then stage according to local conditions as storms get closer.Higher elevations will face a different transportation threat as snow levels fall through the weekend. A winter storm watch remains in effect for those higher elevation zones from Friday through Monday, although the watch doesn’t cover Plumas County as a whole.Warnings can still be issuedThe retirement of Dixie’s special thresholds also doesn’t mean NWS has stopped watching the area.Forecasters said they can issue traditional flash flood warnings if rainfall or hydrologic conditions warrant them. During this week’s storms, they’ll monitor rainfall rates, radar and reports from CHP to determine whether a warning is needed.NWS officials previously said reports of rockslides, rapidly moving water or prolonged heavy rainfall are among the conditions that can contribute to a warning decision.For Plumas County residents, Pini urged preparation before conditions deteriorate.OES recommends signing up for Genasys emergency notifications and making sure the system has the correct home address. Because many Plumas County communities are rural and winter storms can disrupt roads and utilities, the county recommends that residents consider keeping enough supplies to remain self-sufficient for a week or longer.Caltrans recommends checking QuickMap before traveling and avoiding roads covered by water or debris. Woodward warned that floodwater can hide damage to the roadway and that an initial rockfall or debris slide may be followed by additional material.Five years after Dixie, the slopes surrounding the Feather River no longer look or respond to rainfall exactly as they did in the fire’s immediate aftermath. But Lindsay said recovery is gradual, and some effects of wildfire can persist for years.</div></body>

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A series of Pacific storms is expected to reach Plumas County starting Friday, bringing rain, gusty winds and a chance of thunderstorms before colder weather introduces some snow. Local and state agencies are watching roads and slopes across the Dixie Fire footprint. For Quincy specifically, the National Weather Service office...

As storms approach, Dixie Fire recovery faces new test

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A series of Pacific storms is expected to reach Plumas County starting Friday, bringing rain, gusty winds and a chance of thunderstorms before colder weath

As storms approach, Dixie Fire recovery faces new test

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