Weird flashes for a split-second

Platform:
PC

Description:
Sometimes there are weird flashes in the water. Usually barely noticeable and remind me more of flashes on the eye’s retina due to radioactive particles or heavy ions. But this time it was quite obvious that there are some graphical glitches in the water.

Steps To Reproduce:
I was running from Hästvik to the Saltholmen naval base southbound when the flashes appeared. But I cannot replicate them.

Images / Videos:

Host or Client:
Both == solo

Players in your game:
Only Mats.

Specifications:
R5 2600, 16GB RAM, Game on PCIe NVMe SSD, Win10 64bit