Hi Martin,
Interesting! I guess the main issue would be wind-direction, but if this isn't being considered in this exercise then your suggestion of using a polygon to represent the 'cloud' would be best. I would make it irregular, rather then just a circle, and make it grey with transparency, so the base mapping can be seen. Here's a couple of examples I've just knocked up using the eclipse tool and then merging objects together.

I guess you could add a symbol to show the point of escape, if that was relevant.
Interesting to see what others come up with.
Greg
------------------------------
Greg Driver
Knowledge Community Shared Account
Shelton CT
------------------------------
Original Message:
Sent: 06-20-2019 04:52
From: Martin Dowler
Subject: Advice on how to display plumes of smoke
I have been asked to generate a map for an emergency planning exercise. There is no data as such but essentially I need to generate a file to be printed out which shows smoke/fumes over a small area from a certain point. It's outside of what I normally do and I wondered if anyone had any visual examples and/or suggestions about how best to achieve it and make it look visually correct (or just appealing). I could just display a polygon over the area and shade it but just wondered if there is a better solution.
Many thanks
Martin
------------------------------
Martin Dowler
CHESHIRE & WIRRAL PARTNERSHIP NHS TRUST
------------------------------