A/T hunting in second gear shift?

[Turbo Terry]

When my truck is first driven (cold) the first few shifts (maybe2-3-4) are funny acting. The transmission starts out fine in 1 st gear then shifts to 2nd. As it goes into 2nd it will jerk or shudder then be OK for the rest of the shifts. If I let the truck warm up (transmission in neutral) it does not do it as bad. Once every thing is warm it shifts fine. Also sometimes in traffic if I,m not on the throttle very hard it will do this even when warmed up. If I push on the throttle harder it shifts fine. Any ideas?