Storm to crawl through southwestern US with rain, snow into late week
By
Renee Duff, AccuWeather senior meteorologist
Updated Mar 10, 2021 2:16 PM EDT
As the calendar seemingly jumps to April across the eastern half of the nation this week, the West will be stuck in a cool and dreary pattern with rain, snow and even hail showers expected each day.
A storm system that has been lurking offshore early this week will slowly pivot southeastward and inland across California and the Southwest during the latter half of the week. Once over land, it will sit, spin and churn out days of unsettled weather.
Some of the steadiest rain and snow from the storm will sweep through California into Wednesday night, but stray rain and snow showers are forecast to linger into Friday across the Southwest.
A look at the radar early Wednesday morning shows needed rain and snow sweeping through California. (AccuWeather)
A general 0.25 to 0.50 of an inch of rain is forecast at most low-elevation locations in Northern California into Thursday.
"There is not an abundance of moisture to work with and no atmospheric river to cause excessive rain with this storm," AccuWeather Senior Meteorologist Mike Doll said.
Despite this, the cumulative effect of the showers and potential for more robust downpours could yield rainfall totals of 0.50-1.00 inch for coastal areas of Southern California into late week. Lesser amounts are expected farther inland across the Southwest.
"West- and southwest-facing slopes in the coast ranges of Southern California could receive well over an inch of rain," Doll said.
The greatest risk for widespread showers and dampened outdoor plans will be through Wednesday around San Francisco, and through Thursday for Los Angeles and San Diego.
"Rain and snow will spread across Nevada and the Four Corners states late Wednesday and Thursday," AccuWeather Lead Long-Range Meteorologist Paul Pastelok said.
Although most of this rainfall will be beneficial due to meager precipitation totals during the winter months and the ongoing drought, it is possible for heavier downpours to trigger localized flooding concerns, especially near burn scar areas. Motorists will want to slow down on the highways amid any downpours to reduce the risk of hydroplaning.
"This storm will feature very cold air high in the atmosphere, so thunderstorms are possible and snow levels will be low," Pastelok said.
Within any embedded thunderstorms, brief heavy rainfall, gusty winds and dangerous lightning can be expected. Small hail is also possible, and it's not out of the question for some areas to pick up enough hail to create slippery roadway conditions. In a couple of instances, there is also the risk of funnel clouds and even a brief tornado or waterspout.
Scenes of hail pelting portions of Washington and Oregon were all too common over the weekend as chilly storm systems moved through the region, and similar videos may come out of California and other parts of the Southwest into late week.
One to 2 feet of snow is expected to pile up in the Sierra Nevada, leading to treacherous travel for motorists over Interstate-80's Donner Pass. Snow will fall heaviest in this portion of the mountains through Wednesday.
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Farther south, over a foot of snow is also possible at the top of the highest peaks of the Southern California mountains, but forecasters say drivers at lower elevations may also need to take caution. Snow levels can dip to 2,500-3,500 feet around the middle of the week, especially in more robust showers. Winter storm warnings are in effect ahead of the snow.
Through Thursday, motorists along I-5 near the Grapevine and through I-15's Cajon Pass could face treacherous conditions with reduced visibility and snow-covered roads. The worst conditions over the Southern California passes in terms of rounds of heavy snow are likely to be from Wednesday to Wednesday night. The snow may be heavy enough to shut down travel.
"With the stormy pattern, temperatures are expected to be several degrees below normal across most of the West this week," Pastelok said.
Downtown Los Angeles may be stuck in the upper 50s around the middle of the week, when highs near 70 F are more typical of the time of year.
In Phoenix, while the city may get little, if any, precipitation from the storm, residents will not escape the chilly air as highs struggle to get out of the lower 60s on Thursday -- a far cry from Sunday's high of 89 and the day's average of 76.
Amid the unsettled pattern, hikers are discouraged from venturing into the high terrain due to the unpredictability of the intensity of the showers, as well as the potential for lightning, thunder, hail and snow.
As the storm pivots inland and strengthens over the interior West, a massive, multiple-day snowstorm is expected to bury Colorado, including the Denver area this weekend. Meanwhile, more flooding and severe weather will target areas farther east.
Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier, Spectrum, FuboTV, Philo, and Verizon Fios.
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News / Weather Forecasts
Storm to crawl through southwestern US with rain, snow into late week
By Renee Duff, AccuWeather senior meteorologist
Updated Mar 10, 2021 2:16 PM EDT
As the calendar seemingly jumps to April across the eastern half of the nation this week, the West will be stuck in a cool and dreary pattern with rain, snow and even hail showers expected each day.
A storm system that has been lurking offshore early this week will slowly pivot southeastward and inland across California and the Southwest during the latter half of the week. Once over land, it will sit, spin and churn out days of unsettled weather.
Some of the steadiest rain and snow from the storm will sweep through California into Wednesday night, but stray rain and snow showers are forecast to linger into Friday across the Southwest.
A look at the radar early Wednesday morning shows needed rain and snow sweeping through California. (AccuWeather)
A general 0.25 to 0.50 of an inch of rain is forecast at most low-elevation locations in Northern California into Thursday.
"There is not an abundance of moisture to work with and no atmospheric river to cause excessive rain with this storm," AccuWeather Senior Meteorologist Mike Doll said.
Despite this, the cumulative effect of the showers and potential for more robust downpours could yield rainfall totals of 0.50-1.00 inch for coastal areas of Southern California into late week. Lesser amounts are expected farther inland across the Southwest.
"West- and southwest-facing slopes in the coast ranges of Southern California could receive well over an inch of rain," Doll said.
The greatest risk for widespread showers and dampened outdoor plans will be through Wednesday around San Francisco, and through Thursday for Los Angeles and San Diego.
"Rain and snow will spread across Nevada and the Four Corners states late Wednesday and Thursday," AccuWeather Lead Long-Range Meteorologist Paul Pastelok said.
Although most of this rainfall will be beneficial due to meager precipitation totals during the winter months and the ongoing drought, it is possible for heavier downpours to trigger localized flooding concerns, especially near burn scar areas. Motorists will want to slow down on the highways amid any downpours to reduce the risk of hydroplaning.
"This storm will feature very cold air high in the atmosphere, so thunderstorms are possible and snow levels will be low," Pastelok said.
Within any embedded thunderstorms, brief heavy rainfall, gusty winds and dangerous lightning can be expected. Small hail is also possible, and it's not out of the question for some areas to pick up enough hail to create slippery roadway conditions. In a couple of instances, there is also the risk of funnel clouds and even a brief tornado or waterspout.
Scenes of hail pelting portions of Washington and Oregon were all too common over the weekend as chilly storm systems moved through the region, and similar videos may come out of California and other parts of the Southwest into late week.
One to 2 feet of snow is expected to pile up in the Sierra Nevada, leading to treacherous travel for motorists over Interstate-80's Donner Pass. Snow will fall heaviest in this portion of the mountains through Wednesday.
CLICK HERE FOR THE FREE ACCUWEATHER APP
Farther south, over a foot of snow is also possible at the top of the highest peaks of the Southern California mountains, but forecasters say drivers at lower elevations may also need to take caution. Snow levels can dip to 2,500-3,500 feet around the middle of the week, especially in more robust showers. Winter storm warnings are in effect ahead of the snow.
Through Thursday, motorists along I-5 near the Grapevine and through I-15's Cajon Pass could face treacherous conditions with reduced visibility and snow-covered roads. The worst conditions over the Southern California passes in terms of rounds of heavy snow are likely to be from Wednesday to Wednesday night. The snow may be heavy enough to shut down travel.
"With the stormy pattern, temperatures are expected to be several degrees below normal across most of the West this week," Pastelok said.
Downtown Los Angeles may be stuck in the upper 50s around the middle of the week, when highs near 70 F are more typical of the time of year.
Related:
In Phoenix, while the city may get little, if any, precipitation from the storm, residents will not escape the chilly air as highs struggle to get out of the lower 60s on Thursday -- a far cry from Sunday's high of 89 and the day's average of 76.
Amid the unsettled pattern, hikers are discouraged from venturing into the high terrain due to the unpredictability of the intensity of the showers, as well as the potential for lightning, thunder, hail and snow.
As the storm pivots inland and strengthens over the interior West, a massive, multiple-day snowstorm is expected to bury Colorado, including the Denver area this weekend. Meanwhile, more flooding and severe weather will target areas farther east.
Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier, Spectrum, FuboTV, Philo, and Verizon Fios.
Report a Typo