I have observed a fair amount of red thread disease this spring. This disease has been most active on perennial ryegrass (see attached image). It has also been seen this spring on tall fescue and fine fescues but to a lesser extent than perennial ryegrass.
Red thread disease tends to be more aggressive in full sun than shade and it often appears where soil fertility and organic matter are low. The recent warm weather will probably make this disease less active but it could resume if cooler wet weather returns. See Fact Sheet FS798 for more details.
Looking forward, turf disease activity is shifting towards brown patch disease as the weather warms. So you could see an influx of inquiries about brown patch if you haven’t already; there was a large increase in this disease at the research farm this weekend. N fertilizer can stimulate brown patch disease, so applicators needs to use moderate to low rates and/or slow N fertilizer.