First time starting from seed

[biodarwin]

Hello folks!

I am wanting to plant some tomatoes for the fall season (zone 8a) and I want to start them from seeds this time around. I bought a germination station which is like a mini green house with a heating mat from amazon. I plant to start the seends sometime in the next 2 weeks or so. Then transplanting into 4" pots when they are ready. I also want to have these indoors for as long as I can, given the heat we have in Louisiana. Ideally I would want to plant in mid-august, but I think that may still be too hot? Am I worring too much and they will be fine outdoors mid August?

One idea was to use an old T-5 216watt, 4ft light (from a former saltwater reef aquarium) to possibly grow them indoors for as long as possible. Should I use a bigger pot than 4" so I can keep them indoors longer? Any advice is greatly appreciated.