They close it during severe weather events. It's usually open after a little rain and snow. It was recently closed around New Year's with the big storms then and reopened on the 6th. They will close the gates, the only way to know in advance is calling the ranger station.
As far as I know this is a year round acsess . However, it does make sense to close the gate when it rains. The dirt road that takes you to the top is fine to drive thru but it's very uneven when there is no rain, I would not want to try getting thru in the rain. The road has some sections that have steep drops on both sides. The scenery is absolutely beautiful, that alone makes the trip worth while.
There is usually no snow moat of the year, unless it's really low snow levels. It is open all year round, rain or shine. Hope this helps. Plz look up Pinnacle4x4ohv in instagram, it's my Jeep and Truck offroaf club in socal
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