Random 1.3.1 Terraria FPS lagspikes

[CanSteam]

When these happen, it often looks like some times suddenly become brighter for no reason, and sometimes, the clouds move ery fast. It's weird; whats the cause?

 

[Leinfors]

1: Do you have frameskip on or off (in the options menu)?
2: What is your monitor size?
3: What is your monitor's refresh rate, if you know it?

Any information you can share will help with diagnosing this issue.