Depending on your location in the northern growing areas, different things are happening.
Dollar spot is very active. Propiconazole is an excellent fungicide to prevent or cure dollar spot. Propiconazole is labelled for both golf and residential turf. Dollar spot initially can be seen as small circular spots, but will progress together to form large affected areas. When looking at the leaf blades, dollar spot forms what is known as an hour glass lesion. Above the disease lesion, the blade will desiccate over time, browning out the turf blade.
In the southern portion of the north, brown patch is becoming very active with the heat and humidity of summer. The Strobe fungicides (Azoxystrobin) is excellent for both preventing and curing brown patch.
The Strobe Family
The latest additions to the Strobe fungicide family are Strobe Pro and Strobe Pro G. These are a combination of Azoxystrobin and Propiconazole. Both of these products are labelled for golf course turf and residential turf. The Strobe Pro G is an easy alternative for lawn care to be able to treat localized areas without having to load a tank.