TYNI wrote:Can anyone identify what the best satellite tool is to utilize in determining the centre of a developing circulation? Visible, RGB, Water Vapour, TPC
I've seen several discussions this season debating a centre location fix by NHC, and have had trouble location a closed low based on a centre fix.
Thanks for helping!
To get a surface center fix in a developing tropical cyclone, you need to see the low cloud field. Visible imagery is a great way to do this, but sometimes high clouds (like cirrus outflow) obscure surface rotation, or, if it's night, for obvious reasons, you can't see the clouds so well.
If visible is not available or doesn't provide the detail for the fix, a couple of options are RGB imagery (which colors low clouds differently from high clouds and can help you sometimes...sometimes...) and Microwave imagery (if you get a good overpass) or scatterometry (ditto).
Identifying a surface circulation from water vapor or infrared imagery in a developing Tropical cyclone is not a good practice. You see it done on these boards sometimes, but it's not a good idea. In a wore developed TC, with a strong circulation, you can use them (becasue the circulation often extends up to where those sensors can "see") though in those cases, visible and Microwave are STILL better in case there is any separation of the low and mid level centers.