HYSPLIT Forum: hysplitbbs.arl.noaa.gov

I would like to do back-trajectories cluster analysis, but I don’t understand this option : in the trajectory setup we put back direction and in the script of the automated trajectories by time will start with the date mentioned in the trajectory setup (not in the back direction)
I select this date 15 june 2017 for example with backward direction with 120 h total run times with the meteorological fil of the month (see figure 1 in the attached file)


Before clustering , I do the automated multiple trajectories by time in order to generate files dump (see figure 2)
The problem here that I would like to do back calculation but here calculation start from 15 june 2017 to 30 june )(see figure 3) not back calculation ??? please explain me this option

(see figure in the attached file)

Any help will be highly appreciated.
I am looking to hear from as soon as possible
Best Regards
Djamel

Open the tdump files you have in Notepad and you will see that because in Trajectory setup you specified 'backward', each trajectory will be backward.

The loop in the Daily trajectory goes forward with time no matter if each trajectory is forward or backward. If you want backward trajectories beginning 15 June and ending 1 June. Then you must specify 1 June as the starting day in Daily.