Mountain weather at ~6,400 ft changes fast — sunshine to snow squalls in an afternoon. Check current conditions before you head up to Loon Lake or Crystal Basin, and don't rely on a single source for safety-critical decisions.
Current conditions & multi-day forecast
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Wind forecast
Live wind map centered on Loon Lake — useful for boaters and paddlers. Winds funnel and gust hard across the open reservoir in the afternoon.
More wind detail: Windfinder · WindAlert · Windy.app.
Nearby: Spider Lake station
A volunteer weather station at nearby Spider Lake (callsign SPDRWX) reports live-ish temperature, wind, and humidity to the APRS/CWOP network. It's the closest continuous readout to Loon Lake, though it is a hobbyist station — not an official gauge — so treat it as a helpful nearby reference.
Seasonal averages
| Month | Avg high (°F) | Avg precip (in) | Snowpack |
|---|---|---|---|
| January | 41 | 10.1 | Yes |
| February | 43 | 8.2 | Yes |
| March | 45 | 7.5 | Yes |
| April | 49 | 4.9 | Yes |
| May | 56 | 2.3 | Yes |
| June | 65 | 0.8 | No |
| July | 72 | 0.2 | No |
| August | 72 | 0.3 | No |
| September | 66 | 1.0 | No |
| October | 57 | 3.0 | No |
| November | 47 | 7.1 | Yes |
| December | 42 | 9.5 | Yes |
Averages from SMUD (precipitation 1962–2007 across five Upper American River Project locations). Recent monthly average air temperatures are also available from CDEC station LON.
Snow & winter conditions
Loon Lake Road (Ice House Rd) and the surrounding Crystal Basin are typically snow-covered and gated in winter; the area is most accessible late spring through fall. Carry chains and check road status before traveling in the cold months.
Caltrans QuickMap (roads & chains) → CDEC snow overview →
Weather resources
- NWS point forecastOfficial Sacramento (STO) forecast
- Caltrans QuickMapLive road, closure & chain control
- CDEC Van Vleck (VVL)Nearest snow-pillow station
- CDEC snow conditionsStatewide / basin snowpack
- AirNowAir quality & wildfire smoke
- Spider Lake (SPDRWX)Nearby volunteer station
- Loon Lake reservoir conditionsLake level & access on this site
Data & attributions: forecast and observations courtesy of NOAA / National Weather Service; wind map by Windy.com; nearby readings from the volunteer Spider Lake (SPDRWX) CWOP operator; snowpack from California CDEC station Van Vleck (SMUD); seasonal averages from SMUD.
