California Avalanche Map Layers

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"What's the danger?" Here are autogenerated DEM Shading rules for each advisory zone that allow for quickly adding avalanche danger, problems, and sun angle layers to CalTopo maps. Reports sourced from avalanche.org.

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Digital Elevation Model (DEM) shading let's you create custom shading schemes based on elevation, slope, aspect and tree cover.

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Avalanche Report

Danger report updates are fetched at 7:33pm and 7:33am. The selected elevation bands are not meant to be exact, but represent a characteristic of the terrain which varies locally.

The highest band typically includes alpine areas beginning as the treeline transitions into open slopes extending to ridges and peaks.

The middle band is typically a narrow transition zone between dense forests and treeless alpine areas.

The lowest band typically extends from valley floors or snowline to near treeline.

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Usage

You'll find that Terrain Modeling in the left pane will show layers that can be turned on and edited. The right pane will show Custom Layers that can be toggled on or off.

Select A Zone: Bridgeport Avalanche Center Eastside Region Mount Shasta Central Sierra Nevada

Avalanche Report

Pre-populated CalTopo Map

2024-12-21 Avalanche Danger

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• Moderate danger (above 8701')
• Moderate danger (6201' to 8700')
• Low danger (below 6200')

2024-12-21 Persistent Slab

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• NW to NE aspects (above 8701')
• NW to NE aspects (6201' to 8700')

Issued at: Friday, December 20, 2024 7:00AM
Issued by: BAC

Avalanche Report

Pre-populated CalTopo Map

2024-12-21 Avalanche Danger

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• Low danger (above 10001')
• Low danger (7801' to 10000')
• Low danger (below 7800')

Issued at: Friday, December 20, 2024 7:00AM
Issued by: ESAC

Avalanche Report

Pre-populated CalTopo Map

2024-12-21 Avalanche Danger

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• Moderate danger (above 8701')
• Moderate danger (6201' to 8700')
• Low danger (below 6200')

2024-12-22 Wind Slab

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• W to SE aspects (above 8701')
• W to SE aspects (6201' to 8700')

Issued at: Saturday, December 21, 2024 6:34AM
Issued by: MSAC

Avalanche Report

Pre-populated CalTopo Map

2024-12-21 Avalanche Danger

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• Moderate danger (above 8701')
• Moderate danger (6201' to 8700')
• Moderate danger (below 6200')

2024-12-21 Persistent Slab

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• NW to NE aspects (above 8701')
• NW to NE aspects (6201' to 8700')
• NW to NE aspects (below 6200')

Issued at: Friday, December 20, 2024 6:30AM
Issued by: SAC

Zone

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