| A, Accumulated |
Data value summed over several previous
measurement periods. |
| AM, Aerial Marker |
A vertical marker with equally-spaced
crossbars at one- and two-foot increments. The depth of snow at
these remote sites is determined by observation from low-flying
aircraft. Snow water equivalent is calculated using measurements
of snowpack density from nearby snow measurement sites. |
| Average |
The mean value for a 30-year base
period. The 30-year average is the accepted standard set by the
World Meteorological Organization. The current base period is
1961-1990. A new 30-year average is calculated every 10 years.
Standard averages are computed for sites having at least 25 years
of data. |
| Basin |
The major drainage area in which a
measuring site is located. |
| Conditional Average |
An average based on less than 25 years
of data. |
| D, Disc., Discontinued |
Site is no longer active and data
collection has been discontinued. |
| Data |
Refers to snow water equivalent or
precipitation amounts. |
| E, Est, Estimate |
Data value developed from a long-term
correlation with a currently measured site. Estimates are provided
when a site has been discontinued or a manual measurement was not
made. |
| Elevation |
The vertical reference of a site
location above mean sea level, measured in feet. |
| Max Date, Maximum Date |
The date when the snow water equivalent
of the seasonal snowpack was at its highest prior to melting. |
| Max SWE, Maximum Snow Water
Equivalent |
The highest recorded value of snow
water equivalent for the seasonal snowpack, in inches. |
| Meltout Date |
The date when the seasonal snowpack was
completely melted at a snow measuring site. |
| Months |
Month names that head data columns in
this report indicate:
- Snow depth and snow water equivalent measurements that are
usually taken near the end or middle of the month, and
reported as first of month or fifteenth of month readings.
This explains why, for example, a February 27 and a March 15
reading are shown under the March column.
- Precipitation increment or catch measured during the month
indicated.
|
| Precipitation |
The liquid equivalent (inches) of
rainfall, snow, sleet, or hail, collected by precipitation storage
gauges. |
| Seasonal Snowpack |
The snowpack that typically starts
accumulating in the fall or early winter and remains until meltout
occurs the following spring or summer. This does not include the
intermittent snowpacks that occasionally occur in the early fall
or early summer. |
| SNOTEL |
Abbreviation for SNOwpack TELemetry. A
west-wide system for obtaining snow water equivalent,
precipitation, air temperature, and other hydrologic measurements
from remote data sites via radio transmission. |
| Snow Course |
A permanently marked data site where
manual snow measurements are collected. |
| Site Number |
An indexing/locating number based on
alpha and numeric grid divisions. Refer to the Data Site Maps
included with the printed version of this report. |
| Snow Depth |
An average of the vertical measurements
of the depth of the snow measured at the snow course sample points
and recorded to the nearest inch. Snow depth at aerial markers is
estimated to the nearest half foot unless a ground measurement is
made. |
| Start Date |
The date when the seasonal snowpack
first began to accumulate at a snow measuring site. |
| SWE, Snow Water Equivalent |
The depth of water in the snowpack, if
the snowpack were melted, expressed in inches. |
| WY, Water Year |
The water year in North America is
referred to as the twelve month period beginning October 1 in one
year and ending September 30 of the following year. The water year
is designated by the calendar year in which it ends. |
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