Exterior paint also needs a dry surface for an even coat and proper adherence. Unfortunately, moisture isn’t a problem in Texas right now. If a fluke rain storm does occur, it’s best to wait at least one full day before painting. Your professional painting company can discuss your exterior paint job to help you understand when is the optimal time for repainting.
When painting outside, it is always best to check the tin for the minimum/maximum temperatures. You must also take into account chill factors, especially on metal, as this can reduce surface temperatures considerably. From a health and safety perspective, there isn't a specific minimum or maximum temperature for a worker to paint in. Dress appropriately and stay ventilated/hydrated.