Wind, downpours and snow accompanying storm crashing into West Coast
By
Maura Kelly, AccuWeather meteorologist
Published Dec 6, 2019 11:41 AM EST
An expansive storm system spreading rain and snow across the West through Saturday is creating dangerous travel conditions across the region.
The storm, which has been slowly moving toward the western United States during the second half of the week, will crash ashore on Saturday.
The first drops of rain arrived along the coast of Northern California on Friday afternoon.
Satellite capture from NOAA GOES-West at 6:30 a.m. Friday, EST.
Showers spread into coastal areas of the Pacific Northwest, including Seattle and Portland, Oregon, on Friday night, as rain picked up in intensity across Northern California.
The intense downpours led to flooding on Highway 1 in Marin County, California, on Friday night, local law enforcement reported.
Rainfall totals can climb toward 2-4 inches in Northern California by the time the heaviest rain is over this weekend.
Occasional downpours can also be accompanied by wind gusts of 40-50 mph, threatening to cause sporadic power outages.
Spotty rain showers are forecast to reach as far south as the Los Angeles Basin into Saturday.
As the storm continues to advance inland into the first half of the weekend, a push of Arctic air will sink south from Canada and a mix of rain and snow can be expected in the interior Northwest.
Mainly snow can be expected above 6,000 feet in the Cascade Mountains, but snowfall totals are expected to remain light. The heaviest snow will be reserved for mountains farther south.
Across the Sierra Nevada Range, snow levels are expected to drop to around 7,000 feet. Snowfall totals can reach 6-12 inches along the range, but the swath of moisture moving across the state can increase totals to around 2-4 feet in the higher peaks.
An AccuWeather Local StormMax™ of 50 inches of snow is expected in the highest terrain of Northern California. Traveling on mountain passes will be difficult for many drivers, as temperatures drop and snow accumulation will fall on many pass levels.
"Motorists traveling through the Sierra Nevada should be aware of chain requirements and be prepared with an emergency survival kit in case their vehicle breaks down or stalls," stated AccuWeather Meteorologist Kyle Elliott.
On Saturday, the heaviest rain will also spread farther inland and along the foothills of the Sierra Nevada.
The risk for flash flooding and mudslides will be greatly increased across the region due to the rounds of storms that have trekked across the region.
The newest burn scars across the region will be the most vulnerable places for mudslides to occur.
The storm will continue to push east Saturday night and into Sunday with valley rain and mountain snow expanding across Montana, Nevada, Utah, western Colorado, Arizona and western New Mexico.
"Some rain will also spread into Southern California as well," according to AccuWeather Expert Meteorologist Dan Kottlowski.
"However, impact over much of Southern California should be less extreme in terms of flooding and mudslide potential," Kottlowski said.
Snow is expected to gradually taper off in the Sierra Nevada as snow arrives in the Rocky Mountains.
The storm is forecast to move into the Midwest during the beginning of the week, where it can produce snow and usher in Arctic air before spreading impacts into the Northeast.
Meanwhile, in California, a quieter weather pattern will take hold.
Download the free AccuWeather app to check the forecast in your area. Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
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News / Winter Weather
Wind, downpours and snow accompanying storm crashing into West Coast
By Maura Kelly, AccuWeather meteorologist
Published Dec 6, 2019 11:41 AM EST
An expansive storm system spreading rain and snow across the West through Saturday is creating dangerous travel conditions across the region.
The storm, which has been slowly moving toward the western United States during the second half of the week, will crash ashore on Saturday.
The first drops of rain arrived along the coast of Northern California on Friday afternoon.
Satellite capture from NOAA GOES-West at 6:30 a.m. Friday, EST.
Showers spread into coastal areas of the Pacific Northwest, including Seattle and Portland, Oregon, on Friday night, as rain picked up in intensity across Northern California.
The intense downpours led to flooding on Highway 1 in Marin County, California, on Friday night, local law enforcement reported.
Rainfall totals can climb toward 2-4 inches in Northern California by the time the heaviest rain is over this weekend.
Occasional downpours can also be accompanied by wind gusts of 40-50 mph, threatening to cause sporadic power outages.
Spotty rain showers are forecast to reach as far south as the Los Angeles Basin into Saturday.
As the storm continues to advance inland into the first half of the weekend, a push of Arctic air will sink south from Canada and a mix of rain and snow can be expected in the interior Northwest.
Mainly snow can be expected above 6,000 feet in the Cascade Mountains, but snowfall totals are expected to remain light. The heaviest snow will be reserved for mountains farther south.
Across the Sierra Nevada Range, snow levels are expected to drop to around 7,000 feet. Snowfall totals can reach 6-12 inches along the range, but the swath of moisture moving across the state can increase totals to around 2-4 feet in the higher peaks.
An AccuWeather Local StormMax™ of 50 inches of snow is expected in the highest terrain of Northern California. Traveling on mountain passes will be difficult for many drivers, as temperatures drop and snow accumulation will fall on many pass levels.
"Motorists traveling through the Sierra Nevada should be aware of chain requirements and be prepared with an emergency survival kit in case their vehicle breaks down or stalls," stated AccuWeather Meteorologist Kyle Elliott.
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On Saturday, the heaviest rain will also spread farther inland and along the foothills of the Sierra Nevada.
The risk for flash flooding and mudslides will be greatly increased across the region due to the rounds of storms that have trekked across the region.
The newest burn scars across the region will be the most vulnerable places for mudslides to occur.
The storm will continue to push east Saturday night and into Sunday with valley rain and mountain snow expanding across Montana, Nevada, Utah, western Colorado, Arizona and western New Mexico.
"Some rain will also spread into Southern California as well," according to AccuWeather Expert Meteorologist Dan Kottlowski.
"However, impact over much of Southern California should be less extreme in terms of flooding and mudslide potential," Kottlowski said.
Snow is expected to gradually taper off in the Sierra Nevada as snow arrives in the Rocky Mountains.
The storm is forecast to move into the Midwest during the beginning of the week, where it can produce snow and usher in Arctic air before spreading impacts into the Northeast.
Meanwhile, in California, a quieter weather pattern will take hold.
Download the free AccuWeather app to check the forecast in your area. Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.