Since the new tanks dlc update, a strange bug related to shadows have started appearing by the shoreline of Altis. After a short research it seems to be appearing in 2 locations so far:
1.
https://steamuserimages-a.akamaihd.net/ugc/2435760684527643070/9251353EFB8145EAA5EF15FA80215F8397952958/
https://steamuserimages-a.akamaihd.net/ugc/2435760684527642859/FD060F8134EE664476ACCDA0816B21FABFE12CB8/
2.
https://steamuserimages-a.akamaihd.net/ugc/2435760684527359783/BC62E6180D7E102DD5B5FE848E0EEB29C4B67BFF/
https://steamuserimages-a.akamaihd.net/ugc/2435760684527642149/8B07143DD94565D052C4A7018D03A54D563DB1A8/
Video :
https://www.youtube.com/watch?v=4hawUHaqY4I
There's a possibility clouds cause this bug as it tends to appear randomly and dissapears after a while.