Cutting your lawn while it is wet is a big mistake. Fortunately we have dry summers in the Boise area, but many people have basically free irrigation, which leads many to over watering. Mowing your lawn while it is dry is less stressful on your grass, prevents ruts, easier on lawn equipment, and mulches better. Under normal circumstances it is best to give your lawn a full day to absorb the moisture that you put on your lawn by irrigation.
If the soil is full of too much moisture it will create ruts from the tires on the mowers. Another tactic to preventing ruts is changing the direction that you mow your lawn so the tires are not following the same path week after week. Changing direction perpendicularly is preferred. Mowing in the same direction each week not only creates ruts, but in can also cause your grass to lay down in the direction that it is mowed over and over. This creates an unhealthy lawn and is difficult to correct.
Dry grass mulches very nicely. It is cut into many tiny pieces and is evenly distributed across your lawn so that the clippings lay there unnoticed. Mulching while the grass is wet causes the grass to clump together which is unsightly and can create dead spots where these clumps lay on your lawn.
Wet grass attaches to the undercarriage of the mower and eventually interferes with the spinning blades, this causes extra wear and tear on the mowers.
Obviously you cannot control the weather and sometimes because of your schedule you will need to mow your lawn when it is wet. All Pro Lawn Service highly recommends that you don't make this a habit and always try and mow your lawn when the grass blades and soil are dry.