Jtds.tmp files

Hello,

I have noticed that C:\Users\metabase\AppData\Local\Temp is flooded with files.
Is there anyone that nows why this is happening and how i can clean it regularly.
I have the free version of metabase and the thing I can see is that it happens once every 30 minutes. The same time as a postgresql-table is updated with new data.
The file is named jtd976566585454.tmp for example.