In response to the Nov. 30/Dec. 1 wind event and resulting damage in the Mammoth Lakes Basin, the U.S. Forest Service reports that it is working cooperatively with the Mammoth Lakes Pack Station, Southern California Edison, the Mammoth Community Water District, Mammoth Mountain Ski Area, the Town of Mammoth Lakes, and owners of recreation residence cabins to remove downed trees, address hazards and restore utility services.
According to a USFS press release, “Final damage totals continue to be tallied as crews are able to clear and enter hazardous areas. To date, it is calculated that more than 600 trees were downed or affected by the storm, possibly many more. All cabin owners and permit holders affected by fallen trees have been notified.
“Clean-up efforts are now focused on removing downed and hazardous trees affecting utilities and in developed recreation areas that are used in the winter and early spring. As weather allows, additional cleanup efforts will commence in developed recreation sites used during summer months, such as campgrounds and trailheads.
“The public is advised against visiting the Mammoth Lakes Basin while cleanup efforts are in progress. Areas posted closed with caution or warning tape, or with signs, are temporarily closed to the public and are illegal to enter. Throughout the Lakes Basin, there are downed trees, partially downed trees, downed power lines, and other hazards that could jeopardize the health and safety of visitors.
“Outside of the groomed trail network that is maintained by Tamarack Cross Country Ski Center, hazardous trees will be present throughout the winter and early summer. Traveling off the groomed network is not recommended – this includes the newly constructed Lakes Basin Path. Visitors traveling off of groomed routes are encouraged to use extreme caution when traveling through the forest.”
Mammoth’s local weatherman, Howard Sheckter reported, “It was quite the Mono Wind Event. The most simplistic explanation is to briefly consider the conditions before and during the event.”
These conditions were highlighted by several days of above normal temperatures with highs as warm as 60 in Mammoth and the 70s recorded in Bishop.
“On Nov. 30, we had a dry cold front come through early in the afternoon, the high for that day occurred about noon,” he continued.
On Dec. 1 the high temp peaked at 26 degrees in snow showers.
Tree damage was most likely due to wave breaking on west side where the strongest winds surfaced on Mammoth Mountain’s back side from time to time over a two to three hour period from 3-6 a.m., according to Sheckter.
“Wave breaking is akin to the upper jet briefly surfacing. Over the top of Mammoth Mountain, winds could have briefly gusted in the 150MPH to 170MPH range as sustained winds on Mammoth Mt. were report by recording equipment at 150MPH pegging limits of equipment,” Sheckter continued. “WSFO-RNO forecaster estimated in their AFD, gusts possible between 170 and 180MPH over the crest. Some of that could have surfaced in the affected areas although at lower speeds.”
Community member, Mike Boucher, who has visited the Lakes Basin since the event reported:
“The downed trees (that are apparent from the main road) begin about 50 yards above the bridge off the new bike trail that goes to the Twin Lakes lookout point. Almost all are off to the right on the Mammoth Mountain side of the road. By no means are all or even most of the trees in that area down, but it is eerie that they all have fallen in the same direction — knocked down from the northeast. The damage increases as you get to the Lake Mary Pack Station. There were quite a few pieces of heavy equipment and trucks working to clear up and remove trees from there. It almost looked like a tornado touched down there, except again, everything was knocked down in the same direction. The pack station itself seemed to be in pretty good shape.
“There were many trees knocked down between the pack station and the water tank and the bridge that crosses a small stream just before you get up to Lake Mary (on the bike path). At that point the bike path is blocked by about 20 downed trees. Once you get up to Lake Mary the forest looks much better. There were several areas with trees downed on the ridge that overlooks Twin Lakes and a good number of trees had fallen on or east of the road right before you get to the Wildeyre Lodge. From that point to Horseshoe Lake there wasn’t much to notice out of the ordinary, aside from crews laying electrical tubes for cable leading to the cabins out on Falls track (where evidently more trees had fallen).
“There was red danger tape off to the right side of Lake Mary Road by the pack station and that was about it for warning signs.”
The Forest Service will issue a follow-up press release when primary hazards have been removed and clean-up efforts are suspended.
For additional information, please contact the Mammoth Lakes Welcome Center at 760.924.5500.