This year the new month commences at 43-52 on Saturday, so it is good to perform masappirappu tarppanam the next day morning i.e. on Sunday morning. It is considered good to perform tarppanam on Sunday, 15th Jan within 1hrs 32mins after sunrise (please refer to any astronomical calendar to check the sunrise time of your zone)
Notes:
uttarayana puNyakAlam is considered up to 20 nAzhigai after Makara sankramanam.
If Makara sankramanam happens in the day then puNyakAlam after the sankramanam is on the same day. If it happens after sunset i.e during the night, then puNyakAlam is on the next day.