I usually plant tomato seeds in peat pellets, then pot up to 2" peat pots,
before finally transplanting them outside.

This year many of my young tomato plants died, so I started a new batch in
peat pellets. The plants all have four new true leaves; some have six or
eight. It is about time to pot them up to the larger pots, but I am
wondering if it would be okay to simply put them out in the ground now. I
know that first transfer helps to develop their roots, but I wonder if they
would still be okay without that intermediate step.

I live in southern Utah, zone 7 or 8, where it is currently about 90 degrees
in the day and 65 at night (around 40 C day and 20 C night).
--S.