Here's my take on watering:

http://lawniac.com/lawn-watering

It's a hands on approach that pushes deep and infrequent to its limits and helps roots go deeper into the soil. It does require that you pay close attention to the lawn.

If you're looking for a more set-it-and-forget-it type approach, irrigate 0.75" of water per thousand when/if you see signs of drought stress through May, then move to 0.75" of water per thousand sq ft every 5 days June through August.

Through all this, remember - if you see signs of drought stress, water - regardless of when you last watered or when your next scheduled irrigation is.

I highly suggest getting on a preventive fungicide regimen starting in May at the latest. Keep an eye on the grass, I'm seeing fungus issues right now.

I would recommend waiting for signs of stress myself. That said, last year I installed Rachio, a "smart" irrigation controller. You configure it to type of grass, soil, terrain, etc. After that it waters based on the local weather. It did a pretty good job last year.

Here's my approach to watering. When I came to this forum in 2002 I was a water-every-day kind of guy. After numerous heated discussions, a lawn care professional in Phoenix convinced me that deep and infrequent was the way to go. There are a number of variables that affect watering, evaporation, and retention in the soil. If you try to take all of them into consideration, you won't have time to enjoy the yard. I have boiled it down to the following.

Watering: Deep and infrequent is the mantra for watering. This is for all turf grass all over the place. Deep means 1 inch all at one time. Put some cat food or tuna cans around the yard, and time how long it takes your sprinkler(s) to fill all the cans. Memorize that time. That will be the time you water from now on. My hose, sprinkler and water pressure takes 8 full hours to fill the cans. Your time will likely be less. I like gentle watering. As for watering frequency, that depends on the daytime air temperature. With temps in the 90s, deep water once per week. With temps in the 80s, deep water once every 2 weeks. With temps in the 70s, deep water once every 3 weeks. With temps below 70, deep water once a month. Note that you have to keep up with quickly changing temps in the spring and fall. This deep and infrequent schedule works in Phoenix and in Vermont, so it should work for you. The reason for deep and infrequent is to grow deeper, more drought resistant roots and to allow the soil to dry completely at the surface for several days before watering again. If it rains, reset your calendar to account for the rainfall.

Ok great. This is some useful information. Thanks everyone. I actually just put down a preventive fungicide this past saturday and plan to continue that monthly or as needed. Attached is a photo of the lawn in its current state

It might be just the picture, but the grass looks short. Make sure you cut at the mower's highest setting. Fescue does well at 3.5"-4".

I cut it down too two inches for the winter. But right now its a little uneven as i have at the lowest point 2.5 all the way to 4 inches at the moment. Plan to run the mower once a week to keep everything at around the 3.5 to 4.5