Highway 145/Glasgow Ave at Rico CO
Ore Cart photo - Dec 29, 2021
Late December 2021 storms pushed snow depths to above normal at Rico and other western Colorado locations. Chart below shows snow depth at weather stations where elevation is similar to Rico.
Ore Cart chart
The U.S. Department of Agriculture (USDA) Natural Resources Conservation Service snow water equivalent map shows averages for Colorado's river system areas and statewide:
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Snow Water Equivalent Map
Colorado River Drainages
- January 4, 2022 -
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A recent National Oceanographic and Atmospheric Adminstration (NOAA) Climate Prediction Center report shows Western Colorado was wetter and warmer than normal in December 2021:
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U.S. temperature
and precipitation departures
- past 30 days -
maps source:
Weekly ENSO Evolution, Status and Prediction Presentations download at Climate Prediction Center El Niño Southern Oscillation site
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Pacific La Niña causes a drier winters?
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The National Climate Prediction Center January 3 El Niño Southern Oscillation (ENSO) update states that La Niña has not gone away, and will continue through winter:
- La Niña is present.
- Equatorial sea surface temperatures (SSTs) are below average across the central and east-central Pacific Ocean.
- The tropical Pacific atmosphere is consistent with La Niña.
- La Niña is favored to continue through the Northern Hemisphere winter 2021-22 (~95% chance) and transition to ENSO-neutral during the spring 2022 (~60% chance during April-June).
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More information about El Niño and La Niña at National Oceanographic and Atmospheric Administration (NOAA) - Resources.
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A forecaster at the National Weather Service (NWS) in Grand Junction explained by phone December 29 that low pressure systems parked over the Pacific Northwest U.S. States created a circulation pattern of atmospheric moisture flow from the Pacific Ocean eastward over the West Coast and to the Rocky Mountains. The forecaster also attributed the wet weather pattern to:
- "other oscillations"
- Colorado is less affected by La Niña compared to other regions
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National Weather Service forecast map for December 29-30, 2021 shows low pressure systems over the Pacific northwest and Californa.
Wind arrows indicating counter-clockwise flow added by Ore Cart.
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The NOAA/NWS glossary explains Low Pressure System and wind circulation:
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Low Pressure System
An area of a relative pressure minimum that has converging winds and rotates in the same direction as the earth. This is counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Also known as a cyclone, it is the opposite of an area of high pressure, or a anticyclone.