Early Snow Storm Strikes Eastern
Washington and North Idaho
Some storm total accumulations
from early Nov 8 to early Nov 9.
LOCATION(S)
ACCUMULATION
Priest Lake, Spirit Lake
5-10"
Sandpoint/Bonners Ferry/Newport/Colville/Republic
1-3"
Deer Park/Colbert/Loon Lake
4-8"
Spokane/Coeur D' Alene
2-5"
Moscow/Pullman/Saint Maries
2-4"
Silver Valley
2-5"
Camas Prairie (Winchester, Craigmont)
4-8"
Okanogan Valley (above 2500
feet)
2-4"
Central Basin
Trace to 2"
Waterville Plateau
4-8"
Methow Valley
2-5"
Lake Wenatchee/Plain
Trace to 2"
A strong low pressure system
on November 8th and 9th brought the first widespread snow for the 2000-2001 cold
season to North Idaho and Eastern Washington. The heaviest snow fell in northeast
Washington and North Idaho above 2000 feet in elevation. Most locations received
2 to 4 inches. However, some localized spots picked up 5 to 10 inches. This included,
Spirit Lake and Priest Lake, as well as Waterville and Winchester. The only locations
that did not receive an accumulating snow were the Central Basin and most locations
along the river valleys below 1200 feet in elevation. This was because temperatures
were too warm. The following review will briefly describe a few of the factors
that lead to the early season snow. A comparison of other early season snow storms
will also be provided.
Click image to see it loop
(135KB)
A low pressure system and
associated cold front swept through Alberta and Saskatchewan and into the Northern
Plains on November 5th (shown in the image to the left). Very cold air swept south
behind the cold front. High temperatures were only reported in the teens and lower
20s in eastern Montana and North Dakota on the 6th and 7th, which is about 30
degrees below normal. As the cold air deepened over the next few days, some of
the cold air spilled over the mountains of Western Montana and into North Idaho
and Eastern Washington. This intrusion of cold air set the initial stage for snow
across North Idaho and Washington.
Click image to see a satellite
loop (260KB)
Meanwhile, a storm south of the Gulf
of Alaska headed toward Washington. The storm was quite weak as it approached
the coast on the 6th and into the afternoon of the 7th. However, the storm quickly
gathered strength the eve of the Presidential Election. By the morning of the
8th, the low pressure system developed into a full fledged storm (as seen by the
satellite image right). As the low pressure deepened over Washington, it pulled
more and more cold air in from the east. Plentiful moisture brought in from the
Pacific Ocean by the low, combined with the cold air, brought snow to many parts
of Washington and North Idaho on the morning of the 8th.
The low pressure system stalled
over Washington on the afternoon of the 8th and remained nearly stationary into
the 9th as it weakened. Light snow continued in many areas through the morning
of the 9th, but most of the accumulating snow had stopped overnight on the 8th.
Although the snow never fell particularly hard, the snow fell steady for 18-24
hours. This allowed for the snow to slowly accumulate over time.
Top 5 biggest 24 hour snowfalls
by Nov 8
at the Spokane Airport (1948-2000)
11/04/1973
9.0"
10/22/1957
5.9"
11/04/1994
5.2"
11/08/2000
4.4"
11/08/1985
4.0"
The amount of snow that fell on Nov
8, 2000 was quite significant for early November. There has only been three other
storms that brought more snow to the Spokane Airport in a 24 hour period by Nov
8 (records have been kept at the Spokane Airport since Dec 1947). However in 1985,
8.1" inches of snow fell from Nov 8 to Nov 9. Records for the Palouse and Camas
Prairie also reveal this storm ranks in the top five 24 hour snowfalls by Nov
8 for those locations. The 4.4" of snow recorded at the Spokane Airport on Nov
8, 2000 is the most snow that has ever been measured on that day. The old record
was 4.0" set in 1985.
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