Another consideration is what is the material thickness, typically A588 has also impact properties requirements and to insure impact properties AND base metal strengths the total heat input prior to welding , the heat of the welding process and cooling period are all essential variables. This metal is in the catagory of HSLA (high strength low alloy) and thermal shock is a concern when planning to keep under bead cracking at an absolute minimun, keeping in mind there is never a 100% guarentee on thicker members, (controlling embrittlement in the heat affected zone is your objective in addition to protecting base metal properties),
1 to 6" thick, the need to control the martensitic formation (because we do have C, Mn, Cr, V, ) Without a controlled heat input you will either distroy yield strength or impact (knotch toughness) properties.
Keep in mind what major weld variables contribute to heat input: weld amperage (wire stick out variations during welding will incr. or decr. arc amps during welding), arc volts and travel speed. Never get in a hurry welding HSLA steels and Quenched and Tempered steels: A588, A514, A517, A542, A242, A508, A542, A592, A709-gr100, HY-80, HY-100, SSS-100, etc. A copy of ASM Handbook Vol. 6 -- WELDING -- will be a constant sourse of information.