In what month do you plant your tomatoes in lower az?
Time to Plant
Certified GKH Gardening Expert
This will all depend on when your temperatures remain above 50 degrees. They don't tend to germinate below this, so as long as there is nothing predicted for a few weeks, then you can plant them then.
You could also start them inside now under some light, and they will be mature earlier, as you will be planting slips then.
Here is an article that will guide you on the care of tomatoes: https://www.gardeningknowhow.com/edible/vegetables/tomato/growing-tomatoes-guide.htm