More Snow to Add to Massive Snowpack in California's Sierra Nevada, Rockies (FORECAST)

Linda Lam
Published: March 3,2017
After a break, another Pacific storm will pile another foot or more of snow in California's Sierra Nevada and northern Rockies into the weekend, adding to what's been a near-record snowpack for late winter.
(MORE: 6 Strange Things We've Seen in the Past Week's Weather)
As of March 2, parts of the Sierra have over 200 inches of snow on the ground, according to the National Resources Conservation Service.

• Leavitt Lake, California (9604 feet elevation): 240 inches
• Mt. Rose Ski Area, Nevada (8801 feet elevation): 207 inches
• Mammoth Mountain, California (8,909 feet elevation): 200 inches

A survey of the Sierra snowpack's water content on March 1 found near historic values from 1983 in the central and southern Sierra, and well-above average water content in the northern Sierra.
In fact, the just-completed October through February period was California's wettest such period on record dating to 1895, according to the Western Regional Climate Center.
The March 2 snowpack in parts of the Rockies, including Farmington, Utah (124 inches), was also the most in at least 20 years.
The familiar wet pattern that has brought copious amounts of precipitation to parts of the West the past few months will return to northern California this weekend and persist into early next week, as another upper-level trough digs southward into the West.

Current Satellite and Moisture

This system will be a colder system, with snow falling in lower elevations of the Pacific Northwest and northern California.
The good news is that this system will not have as much moisture as many of the storms that brought flooding to northern California this winter.
(MORE: California Storm, Flood Damage Could Top $1 Billion)

Forecast Details

Saturday

• The cold front will drop into northern California, allowing rain and snow to continue spreading south and east.
• Rain is expected in northern California, with snow in the Sierra and much of the Pacific Northwest, as cold temperatures move into the region.
• Snow will fall at elevations as low as 500 feet in Washington and 1,000 feet in Oregon by Saturday night for much of the Northwest.
• Gusty winds are expected to accompany the cold front, with strong gusts possibly impacting travel in the Sierra.
• Snow will fall at elevations as low as 4,000 feet in the Sierra, falling overnight into Sunday.
• Snow will also fall in parts of the northern Rockies.
• FORECAST: San Francisco | Fresno, California | Reno, Nevada

Saturday's Forecast

Sunday

• Showers may reach into portions of Southern California, while the chance for rain continues in northern California.
• Snow will continue to fall across much of the Pacific Northwest, Sierra, the northern Great Basin and northern Rockies.
• Windy conditions are expected in most of the West, with the strongest gusts likely in portions of California and the Great Basin.
• FORECAST: Sacramento | South Lake Tahoe | Los Angeles 

Sunday's Forecast

Monday

• Rain and snow showers, along with some breezy conditions, will linger in northern California and the Pacific Northwest.
• Snow is expected to fall at elevations as low as 500 feet.
• FORECAST: Portland, Oregon | Medford, Oregon | Spokane, Washington

Monday's Forecast

How Much Rain and Snow

• Rainfall in central and northern California is generally expected to be less than an inch.
• Some of the foothills of the Sierra may see rainfall totals up to 3 inches.
• Some debris flows are possible in burn areas, but, in general, widespread flooding is not expected.
• Snowfall totals of a foot or more are likely in the Sierra, Cascades, and high country of Idaho and western Wyoming. Up to 3 feet of snow may blanket parts of the Sierra's highest elevations.
• Light snowfall accumulation is possible in some lowland locations of the Pacific Northwest and northern Great Basin, including Seattle and Portland, especially Sunday and Monday mornings.

Rain and Snow Forecast

In the Sierra, snow will become more of a fluffy, light snow behind the cold front. This combined with high snowfall rates and gusty winds may create areas of blowing and drifting snow, making for dangerous travel conditions.
(MAPS: Weekly Planner)
Since much of the precipitation in the mountains will fall as snow, runoff is expected to be limited, which will hopefully not add to the flooding concerns in northern California.
Little, if any, rainfall is expected in Southern California, where some drought conditions remain. However, as of Feb. 28, 2017, only 8.73 percent of the state remains in drought, according to the U.S. Drought Monitor. This is the lowest percentage of California in drought since Dec. 27, 2011.
An active pattern will likely continue in parts of the Pacific Northwest next week, but temperatures should begin to warm midweek. Some areas of the West may see more spring-like weather by late week.
MORE: California Flood Aerials (PHOTOS)

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