| Mount Dione | |
| Elevation M: | 2589 |
| Elevation Ref: | [1] |
| Prominence M: | 129 |
| Range: | Tantalus Range Pacific Coast Ranges |
| Parent Peak: | Mount Tantalus (2608 m) |
| Listing: | Mountains of British Columbia |
| Location: | Tantalus Provincial Park British Columbia, Canada |
| District: | New Westminster Land District |
| Map: | Canada British Columbia#Canada |
| Map Size: | 270 |
| Label Position: | right |
| Coordinates: | 49.8158°N -123.3292°W |
| First Ascent: | 1916 by J. Fyles and T. Fyles |
| Easiest Route: | Scrambling Southeast Ridge |
Mount Dione is a 2589abbr=offNaNabbr=off summit located in the Tantalus Range, in Tantalus Provincial Park, in southwestern British Columbia, Canada. It is situated 170NaN0 northwest of Squamish, and 0.240NaN0 north of Mount Tantalus, which is its nearest higher peak and the highest peak in the Tantalus Range.[2] The Dione Glacier lies on the southern slope, and the Rumbling Glacier lies to the northeast. Precipitation runoff from the peak drains east into tributaries of the Squamish River, or west into tributaries of the Clowhom River. The first ascent of the mountain was made in 1916 by Tom Fyles and his brother, John Fyles, via the southeast ridge.[1] The mountain names in the Tantalus Range have a Greek mythology theme, and Mount Dione was named for Dione, the wife of Tantalus.[1] The mountain's name was submitted by Neal Carter of the British Columbia Mountaineering Club, and was officially adopted on June 6, 1957, by the Geographical Names Board of Canada.[3]
Based on the Köppen climate classification, Mount Dione is located in the marine west coast climate zone of western North America.[4] Most weather fronts originate in the Pacific Ocean, and travel east toward the Coast Mountains where they are forced upward by the range (Orographic lift), causing them to drop their moisture in the form of rain or snowfall. As a result, the Coast Mountains experience high precipitation, especially during the winter months in the form of snowfall. Temperatures can drop below −20 °C with wind chill factors below −30 °C. The months July through September offer the most favorable weather for climbing Dione.
Established rock climbing routes on Mount Dione:[1]