California Avalanche Map Layers

---

"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.

Show Instructions

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

---

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.

---

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

Copy to clipboard

Pre-populated CalTopo Map

Pre-populated CalTopo Map

Pre-populated CalTopo Map

Pre-populated CalTopo Map

Download Zone Shape

Download Zone Shape

Download Zone Shape

Download Zone Shape

Bridgeport Avalanche Center
Avalanche Report

2024-04-09 Avalanche Danger

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

a0-0e8701-20310f fff200
a0-0e6201-8700f fff200
a0-0e0-6200f 50b848

Copy to clipboard

2024-04-08 Wind Slab

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

a293-158e8701-20310f A200FF
a293-158e6201-8700f A200FF

Copy to clipboard

Issued at: Sunday, April 07, 2024 7:00AM
Issued by: BAC

Eastside Region
Avalanche Report

2024-04-09 Avalanche Danger

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

a0-0e10001-20310f fff200
a0-0e7801-10000f 50b848
a0-0e0-7800f 50b848

Copy to clipboard

2024-04-09 Wind Slab

• All aspects (above 10001')

a158-158e10001-20310f A200FF

Copy to clipboard

2024-04-09 Wet Loose

• E to W aspects (above 10001')
• E to W aspects (7801' to 10000')
• E to W aspects (below 7800')

a68-293e10001-20310f 0000FF
a68-293e7801-10000f 0000FF
a68-293e0-7800f 0000FF

Copy to clipboard

Issued at: Monday, April 08, 2024 7:00AM
Issued by: ESAC

Mount Shasta
Avalanche Report

2024-04-09 Avalanche Danger

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

a0-0e8701-20310f 50b848
a0-0e6201-8700f 50b848
a0-0e0-6200f 50b848

Copy to clipboard

2024-04-09 Wet Loose

• All aspects (6201' to 8700')
• All aspects (below 6200')

a23-23e6201-8700f A200FF
a23-23e0-6200f A200FF

Copy to clipboard

Issued at: Monday, April 08, 2024 6:39AM
Issued by: MSAC

Central Sierra Nevada
Avalanche Report

2024-04-09 Avalanche Danger

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

a0-0e8701-20310f fff200
a0-0e6201-8700f fff200
a0-0e0-6200f fff200

Copy to clipboard

2024-04-09 Wet Loose

• SE to W aspects (above 8701')
• All aspects (6201' to 8700')
• All aspects (below 6200')

a113-293e8701-20310f A200FF
a113-113e6201-8700f A200FF
a158-158e0-6200f A200FF

Copy to clipboard

2024-04-09 Wind Slab

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

a113-23e8701-20310f 0000FF
a113-23e6201-8700f 0000FF

Copy to clipboard

Issued at: Monday, April 08, 2024 6:40AM
Issued by: SAC

Sunlight Angles

Time of day	Lighting (Az/Z)
2024-04-08 06:40AM Shade	81 by 1 Copy to clipboard
2024-04-08 08:10AM Shade	95 by 18 Copy to clipboard
2024-04-08 09:40AM Shade	111 by 36 Copy to clipboard
2024-04-08 11:10AM Shade	134 by 51 Copy to clipboard
2024-04-08 12:40PM Shade	171 by 59 Copy to clipboard
2024-04-08 02:10PM Shade	212 by 55 Copy to clipboard
2024-04-08 03:40PM Shade	240 by 43 Copy to clipboard
2024-04-08 05:10PM Shade	259 by 26 Copy to clipboard
2024-04-08 06:40PM Shade	273 by 9 Copy to clipboard

Sunlight Angles

Time of day	Lighting (Az/Z)
2024-04-09 06:40AM Shade	81 by 1 Copy to clipboard
2024-04-09 08:10AM Shade	95 by 19 Copy to clipboard
2024-04-09 09:40AM Shade	111 by 37 Copy to clipboard
2024-04-09 11:10AM Shade	134 by 52 Copy to clipboard
2024-04-09 12:40PM Shade	172 by 60 Copy to clipboard
2024-04-09 02:10PM Shade	214 by 56 Copy to clipboard
2024-04-09 03:40PM Shade	242 by 43 Copy to clipboard
2024-04-09 05:10PM Shade	260 by 26 Copy to clipboard
2024-04-09 06:40PM Shade	274 by 8 Copy to clipboard

Sunlight Angles

Time of day	Lighting (Az/Z)
2024-04-09 06:50AM Shade	81 by 1 Copy to clipboard
2024-04-09 08:20AM Shade	96 by 18 Copy to clipboard
2024-04-09 09:50AM Shade	113 by 35 Copy to clipboard
2024-04-09 11:20AM Shade	136 by 49 Copy to clipboard
2024-04-09 12:50PM Shade	171 by 56 Copy to clipboard
2024-04-09 02:20PM Shade	210 by 53 Copy to clipboard
2024-04-09 03:50PM Shade	238 by 41 Copy to clipboard
2024-04-09 05:20PM Shade	257 by 26 Copy to clipboard
2024-04-09 06:50PM Shade	273 by 9 Copy to clipboard

Sunlight Angles

Time of day	Lighting (Az/Z)
2024-04-09 06:40AM Shade	80 by 1 Copy to clipboard
2024-04-09 08:10AM Shade	95 by 18 Copy to clipboard
2024-04-09 09:40AM Shade	111 by 35 Copy to clipboard
2024-04-09 11:10AM Shade	134 by 50 Copy to clipboard
2024-04-09 12:40PM Shade	170 by 59 Copy to clipboard
2024-04-09 02:10PM Shade	211 by 55 Copy to clipboard
2024-04-09 03:40PM Shade	239 by 43 Copy to clipboard
2024-04-09 05:10PM Shade	258 by 27 Copy to clipboard
2024-04-09 06:40PM Shade	273 by 9 Copy to clipboard

---

Change Regions: California Wyoming Oregon Alaska Montana Idaho Arizona New Hampshire Washington New Mexico Utah Colorado Canada

If you enjoyed this or found it helpful, please consider buying an espresso to keep the flow going.

Show Known Issues