Who doesn't like a nice blue background behind their subjects? Usually for warblers that's blue sky. But when spring is cold (news flash, spring has been cold), the insectivores stay close to water where there may be more bugs. There was a nice flock of yellow-rumps along North Lake in Grand Mere, and many were foraging low hoping to find some emergent insect. I couldn't tell how much success they were having, but it reached high 50's today, so hopefully they did better in the afternoon.