Snow/Ice Event, December 29, 2003- early January, 2004

December 29:

The largest snow storm in several years brought significant snowfall totals to most of Oregon. A combination of cold air near the surface, and overrunning moist air from a Pacific weather system, was responsible for the snow. The National Weather Service (NWS) issued the following statement at 8:30 a.m. on 12/29:

An upper level trough and surface low pressure area moving across the Oregon this morning have combined to pull cold moist air into the forecast area. This has produced areas of heavy snow. Several feet of snow have fallen in the Cascades over the past 24 hours with a foot of snow in the Salem area and 1 to 3 inches so far around the Portland area...heaviest near Oregon City and Wilsonville.

Earlier, NWS had issued warnings for many parts of the state. These were issued at 7:34 a.m.:

Portland area:
A heavy snow warning continues. The snow level has lowered to at or near valley floor this morning. Snow accumulations of 1 to 4 inches can be expected above 200 feet...and at the valley floor one to 3 inces of snow accumulation is likely in some areas before the snow ends later today.
Salem area:
The snow level this morning has lowered to near valley floor in some areas. Reports this morning in the Salem area are 4 to 6 inches of new snow with 10 to 12 inches in the higher outlying areas above around 200 feet.

A radar image at 8:30 a.m. shows the extent of the snow falling at that time (blue areas).

Near Corvallis, the Hyslop Experiment Station reported 3.8 inches of snow as of 8 a.m. This was a new daily record for December 29 (old record was 1.3 inches in 1971, and records go back to 1889), and the largest one-day event since 6" was reported in February, 1993. Even if no additional snow falls this year, 2003's annual total (currently 3.8 inches!) will be the largest since the 5.0 inch total in 1995.

Oregon State University's campus received 3-4 inches by 8 a.m. Pictured here are the baseball stadium and the Valley Library quad on 12/29 at 8:30 a.m.

East of the Cascades, snowfall totals were also unusually high. Some of the totals of new snowfall reported for the morning of 12/29 included:

Cascade totals were even higher:

Snow is expected to end by midday, 12/29.

January Snows

An additional big snow storm began on the morning of January 2. A surface low moved onshore, causing a wrap-around effect which brought more cold air to areas west of the Cascades. Moisture from the system fell as snow.

The surface analysis from the Weather Channel at 11:59 a.m. PST on the 1st shows the low center over north central Oregon and the snow wrapping around the low in a counter-clockwise manner.

The radar summary for 11 a.m. shows the snow highlighted in blue.

Satellite pictures for 11 a.m. include the visible, enhanced infrared, and water vapor images. The fronts analysis using an IR image shows the position of the low as well as the cold front. Notice the very cold air offshore, as indicated by the speckled pattern in the clouds.

Web cameras operated by the Oregon Department of Transportation (ODOT) showed very messy conditions at 11 a.m.:

ODOT's text summary of road conditions appears here. For the first time in recent memory (at least), chains were required along the entire length of I-5 through Oregon.

Steve Pierce (Vancouver) and Karri Pasteris (Tigard) kindly provided pictures from their homes.

January Ice

Cold air remained over all of Oregon for the first week in January. On January 5, a Pacific storm approached the Oregon coast. Rain began to fall in the southern Willamette Valley in the early hours of January 6. As the rain reached the ground, it generally froze on contact with objects (roads, cars, trees, and so on) that had been chilled by the cold temperatures -- the dreaded "freezing rain." Icy roads made driiving hazardous. Many trees were damaged or destroyed by large amounts of ice adhering to branches. Downed power lines (often due to falling trees) caused power outages.

Portland Airport saw many flights cancelled on the evening of January 6 and the morning of the 7th. The following was issued by the airport on January 7:

"Inclement Weather Notice
As of 9:30 a.m. on Wednesday, January 7, 188 flights have been cancelled in and out of Portland International Airport (PDX).
We continue to expect many cancellations, but the status of flights is dependent on the weather and determined by each individual airline. Please check the "Flight Search" Web page for more information, or contact your airline. For a list of airlines and their phone numbers, visit our "Airlines" page. 
Airport Way is open, but very slippery from the I-205 interchange to the Terminal. All parking lots are open and the buses which serve the surface lots are running on schedule. Airport MAX, along with the total MAX system, is out of service. Travelers wishing to use public transportation can ride a bus to and from PDX, via the Gateway Transit Center for more information visit the Tri-Met Web site at www.trimet.org."

Roads were a mess. KGW-TV (Portland) reported the following road closures and problems on January 7:

-- I-84 remained closed between Troutdale and Hood River.

-- Highway 20 was closed east of Newport.

-- Oregon State Police required motorists on I-5 to use chains or traction devices between Wilsonville and Jefferson, south of Salem.

-- Motorists were urged to use chains for driving on all Portland-area freeways.

-- One lane of SR 14 was blocked by a snowslide near Bingen and WSDOT crews were trying to limit traffic to only local residents.

-- State Route 14 between Washougal and the Bridge of the Gods was completely closed.

-- Highway 224 remained closed near Carver.

-- Highway 35 south of Hood River was closed to trucks due to the weather.

-- The Astoria Bridge was closed.

-- A stuck car was blocking one lane of I-405 northbound at 4th Avenue.

-- Clackamas County road crews reported dangerous conditions countywide. Roads were a solid sheet of ice in north county east to Sandy and snowy conditions persisted from Sandy east. South county is icy, but road workers reported some thaw from Mulino south. Freezing rain continues in most areas of the county except east of Sandy where it is snowing.

Steve Pierce (Vancouver) kidly provided the following photos:

Ice on branches

Icicles

Icicles2

Icy tree

In Corvallis, snow was followed by a severe freezing rain event. The biggest casualties were trees and power lines. The following pictures were taken by Chris Daly of OSU: