Looks like either Red Thread or Pink Patch, that pink color you are seeing is a characteristic of both diseases. Red thread tends to be pretty benign, although unsightly, and will usually resolve itself without chemical fungicides. Red thread often strikes nitrogen deficient turf, but it can be found on healthy turf as well. Pink Patch is similar in that it produces pink color, and is fairly benign, but with Pink Patch you get cottony growths on the blades, unlike Red Thread's antler like growths from the tips of leaf blades. Again, low nitrogen can be a factor, but the main one is turf that is constantly wet for extended periods of time like your are having in Long Island.

Thanks for replying and your knowledge. I doubt my lawn is nitrogen deficient. I applied Lesco weed and feed approx 3 weeks ago. Back in early April, I applied Lesco fertilizer and crabgrass control. The lawn is growing rapidly and a dense shade of green which I always thought was a sign of good nitrogen levels (I'm no expert though)

I have only found this so far in one area of my yard (approx 40'x60' area) I have slowly started to see it creep away from this area to the surrounding turf.

I haven't ran the sprinklers in about a week but we consistantly have been having overcast weather and on and off showers which I assume is not helping this situation. Any other advice?

Yup, you are fertilizing too much. You should do most of your feeding (especially synthetic ferts) in late summer and fall. Also I wouldn't use Weed and Feed. Kill weeds with herbicides when they are a problem, and fertilize your lawn at the correct time (for LI right around now is when you want to drop your fertilizer). I would recommend no more synthetic N fertilzer until Labor Day. If you use organics you can apply those more liberally in spring, but I wouldn't go crazy with those either. In my original post I wrote low N can be a factor in those diseases, but obviously this is not true in your case.

While I agree with Tiemco's sentiment, there is a complication that Tiemco needs to be aware of. Homeowners in NY cannot get most good pre-emergents without fertilizer. The fertilizer in the pre-m may have been the 0-0-7 Dimension (how's that for getting around the law?). I'm not saying it was 0-0-7, but that is listed as "pre-emergent plus fertilizer" in NY.

+1 on the weed-and-feed opinion.

Good point Andy, I always forget about NY's fertilizer laws. If you can get low or no nitrogen fertilizer with preemergents then that's the way to go, but if you can't, then I understand.