Series of storms to deliver a wet, wintry start to 2020 in the northwestern US
By
Courtney Travis, AccuWeather senior meteorologist
Published Dec 29, 2019 5:16 PM EDT
After a drier-than-normal last week of 2019, a shift in the pattern will allow for multiple storms to target the Pacific Northwest at the start of the new year.
The high pressure that kept it on the drier side has moved into the center of the country, allowing for the jet stream, and thus the weather pattern, to shift in the Northwest.
"While many across the country will be reveling in the new year in dry conditions, those in the Northwest may be an exception," said AccuWeather Senior Meteorologist Brett Anderson.
During Tuesday, a storm will move in from the Pacific Ocean and deliver periods of rain from coastal Washington to the Cascades.
By the evening hours, wet weather is expected to spread into northwestern Oregon and northern Idaho, while rain becomes steadier in Washington. Most of Oregon will be rain, while snow will fall in Idaho.
Snow will be expected in the Washington Cascades to about 4,000 to 4,500 feet, which will allow for a little snow in some of the higher passes, while precipitation remains as rain for the lower elevations.
By Wednesday, New Year's Day, precipitation is expected to lighten up in most areas for the first day of 2020. However, wet weather will be far-reaching. While showers continue for Washington and Oregon, west of the Cascades, snow will stretch from the highest elevations of the Cascades to Wyoming and even the Colorado Rockies.
Overall, cool air will be left behind the storm in the Northwest.
For the first few days of the year, afternoon high temperatures will be near normal for early January, following above-normal temperatures at the end of 2019.
"A bit of a lull is expected in most of Washington and Oregon late Wednesday into Thursday where precipitation will be lighter and it could turn dry for a time," said AccuWeather Senior Meteorologist Alan Reppert.
But another storm will follow quickly.
As Thursday progresses, precipitation will once again increase in the region. While rain is expected near sea level, the colder air already in place across the region will allow for more widespread snow.
"Much lower snow levels, perhaps to 1,500 feet, at the onset of the storm on Thursday will not only make for difficult travel over the major passes through the Cascades in Washington, but snow can fall on the hilltops around Seattle for a time," according to AccuWeather Senior Meteorologist Alex Sosnowski.
Snow levels in Oregon will be around 3,500 feet Wednesday night and early on Thursday, bringing rounds of to snow to passes like Santiam and Willamette.
A little snow could mix in with rain along the higher elevations of US 26, and still cause slippery conditions.
Those traveling across the region should use caution and have their automobile prepared for any driving through higher elevations. Motorists should not travel through the passes unless their vehicle is properly equipped for winter driving, including snow chains. Snow may be intense enough over the passes where some roads may close for a time.
"The weather pattern in the Northwest will be a boon for ski interests. Snow over the high country in the Washington Cascades and Olympics is likely to range between 1 and 3 yards this week alone," Sosnowski stated.
Wet weather may linger from the Washington and Oregon coastlines to Wyoming and Montana through the weekend. Much of the precipitation across interior parts of the Northwest are expected to fall as snow.
"Snow levels may rise enough by Friday to raise the risk of avalanches and flooding as rain falls at some of the intermediate elevations in western Washington and Oregon," Sosnowski added.
The pattern into this weekend is likely to bring a general 3-6 inches of rain in low-elevation, coastal areas of Washington and northwestern Oregon with an AccuWeather Local StormMax™ of 12 inches on the west-facing slopes of the Olympics and Cascades. Enough rain can fall to lead to incidents of flash flooding and mudslides, while the varying snow levels will raise the risk of avalanches.
An active weather pattern is expected across much of the country into the first weekend of the new year. Although there could be a brief break in the wet weather following the weekend, another storm could bring more rain and mountain snow by the middle of January.
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
Series of storms to deliver a wet, wintry start to 2020 in the northwestern US
By Courtney Travis, AccuWeather senior meteorologist
Published Dec 29, 2019 5:16 PM EDT
After a drier-than-normal last week of 2019, a shift in the pattern will allow for multiple storms to target the Pacific Northwest at the start of the new year.
The high pressure that kept it on the drier side has moved into the center of the country, allowing for the jet stream, and thus the weather pattern, to shift in the Northwest.
"While many across the country will be reveling in the new year in dry conditions, those in the Northwest may be an exception," said AccuWeather Senior Meteorologist Brett Anderson.
During Tuesday, a storm will move in from the Pacific Ocean and deliver periods of rain from coastal Washington to the Cascades.
By the evening hours, wet weather is expected to spread into northwestern Oregon and northern Idaho, while rain becomes steadier in Washington. Most of Oregon will be rain, while snow will fall in Idaho.
Snow will be expected in the Washington Cascades to about 4,000 to 4,500 feet, which will allow for a little snow in some of the higher passes, while precipitation remains as rain for the lower elevations.
By Wednesday, New Year's Day, precipitation is expected to lighten up in most areas for the first day of 2020. However, wet weather will be far-reaching. While showers continue for Washington and Oregon, west of the Cascades, snow will stretch from the highest elevations of the Cascades to Wyoming and even the Colorado Rockies.
Overall, cool air will be left behind the storm in the Northwest.
For the first few days of the year, afternoon high temperatures will be near normal for early January, following above-normal temperatures at the end of 2019.
Related:
"A bit of a lull is expected in most of Washington and Oregon late Wednesday into Thursday where precipitation will be lighter and it could turn dry for a time," said AccuWeather Senior Meteorologist Alan Reppert.
But another storm will follow quickly.
As Thursday progresses, precipitation will once again increase in the region. While rain is expected near sea level, the colder air already in place across the region will allow for more widespread snow.
"Much lower snow levels, perhaps to 1,500 feet, at the onset of the storm on Thursday will not only make for difficult travel over the major passes through the Cascades in Washington, but snow can fall on the hilltops around Seattle for a time," according to AccuWeather Senior Meteorologist Alex Sosnowski.
Snow levels in Oregon will be around 3,500 feet Wednesday night and early on Thursday, bringing rounds of to snow to passes like Santiam and Willamette.
A little snow could mix in with rain along the higher elevations of US 26, and still cause slippery conditions.
Those traveling across the region should use caution and have their automobile prepared for any driving through higher elevations. Motorists should not travel through the passes unless their vehicle is properly equipped for winter driving, including snow chains. Snow may be intense enough over the passes where some roads may close for a time.
"The weather pattern in the Northwest will be a boon for ski interests. Snow over the high country in the Washington Cascades and Olympics is likely to range between 1 and 3 yards this week alone," Sosnowski stated.
Wet weather may linger from the Washington and Oregon coastlines to Wyoming and Montana through the weekend. Much of the precipitation across interior parts of the Northwest are expected to fall as snow.
"Snow levels may rise enough by Friday to raise the risk of avalanches and flooding as rain falls at some of the intermediate elevations in western Washington and Oregon," Sosnowski added.
The pattern into this weekend is likely to bring a general 3-6 inches of rain in low-elevation, coastal areas of Washington and northwestern Oregon with an AccuWeather Local StormMax™ of 12 inches on the west-facing slopes of the Olympics and Cascades. Enough rain can fall to lead to incidents of flash flooding and mudslides, while the varying snow levels will raise the risk of avalanches.
An active weather pattern is expected across much of the country into the first weekend of the new year. Although there could be a brief break in the wet weather following the weekend, another storm could bring more rain and mountain snow by the middle of January.
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.
Report a Typo