FOLSOM  (AP) — Search crews have temporarily suspended their search for four men who are presumed dead after their speedboat capsized on a lake east of Sacramento.

California parks department spokeswoman Vicky Waters said high winds and poor visibility forced the dive teams that had been scouring Folsom Lake on Sunday to stop looking for the men, who have not been seen since their boat overturned on Saturday afternoon.

Waters says the search will resume on Monday and is considered a recovery operation instead of a rescue at this point.

Investigators are trying to determine why the 35- to 40-foot vessel capsized. Waters says the accident happened in a part of the man-made lake dotted with small islands and where the water’s depth is much shallower.

The men have been identified as 54-year-old Toby Strauch, 47-year-old James Strauch, 53-year-old Jake Jacobs and 48-year-old Jon Smith, all from the Sacramento area.