<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hey,<div class="">what you want to perform is a cyclone tracking. There are many examples on the NCL website regarding how to find the lot-lan indices of a multi-dimensional array (see Example 3 here <a href="https://www.ncl.ucar.edu/Document/Functions/Built-in/minind.shtml" class="">https://www.ncl.ucar.edu/Document/Functions/Built-in/minind.shtml</a>). You just have to develop something out of this. </div><div class=""><br class=""></div><div class="">Please note that if you want to track the cyclone movement you need to develop a conditional sampling that does not consider the entire domain when looking for the MSLP minimum. I suggest you to have a look at the relevant literature before starting to write a NCL script. </div><div class=""><br class=""></div><div class="">Mary is trying to publish one of my script that allows to track a cyclone directly from the output but we still need to adapt it. I'm attaching the script that I'm using for regular lat-lon grid but I believe it would take it more time for you to understand all my notations than to write your own :) </div><div class=""><br class=""></div><div class="">Good luck </div><div class=""></div></body></html>