I just selected real weather updated every 15 minutes.

 

This could be another source - when using FSX directly, sometimes a bad update is applied, and so pressure goes to zero, or temperature becomes extremely high, causing similar issues to what you are seeing.

 

An external weather program should fix this as they seem to do a sanity check on the data, preventing these extremes.

 

Best regards,

Robin.

It just sounds like the sudden wind shift issue to me.

 

Registered FSUIPC, use wind smoothing. Tick the box to supress turbulence.

Thanks to you both, Martin & Rob. Like you said, what did the Aces Team know about meteorology. Reckon I'll go to REX or get the registered FSUIPC