One way...
[{"id":"87f2e728.b0f2b8","type":"cronplus","z":"50866d2.d5b4b94","name":"at 6am","outputField":"payload","timeZone":"","persistDynamic":false,"commandResponseMsgOutput":"output1","outputs":1,"options":[{"name":"schedule1","topic":"morning","payloadType":"json","payload":"{\"command\":\"describe\",\"expressionType\":\"solar\",\"location\":\"54.9992500,-1.4170300\",\"solarType\":\"selected\",\"solarEvents\":\"sunrise\",\"timeZone\":\"Europe/London\"}","expressionType":"cron","expression":"0 0 6 * * * *","location":"","offset":"0","solarType":"all","solarEvents":"sunrise,sunset"}],"x":490,"y":340,"wires":[["1ed3b3b6.124ecc"]]},{"id":"1ed3b3b6.124ecc","type":"cronplus","z":"50866d2.d5b4b94","name":"","outputField":"payload","timeZone":"","persistDynamic":false,"commandResponseMsgOutput":"output1","outputs":1,"options":[],"x":740,"y":340,"wires":[["5e4e408f.71d81"]]},{"id":"e6e3dc17.ed21e","type":"debug","z":"50866d2.d5b4b94","name":"it is 6am and sunrise has passed","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1160,"y":320,"wires":[]},{"id":"5e4e408f.71d81","type":"switch","z":"50866d2.d5b4b94","name":"is day?","property":"payload.result.solarState.day","propertyType":"msg","rules":[{"t":"true"},{"t":"else"}],"checkall":"true","repair":false,"outputs":2,"x":900,"y":340,"wires":[["e6e3dc17.ed21e"],["a6e4017a.2bf3a"]]},{"id":"a6e4017a.2bf3a","type":"debug","z":"50866d2.d5b4b94","name":"it is 6am and sunrise is yet to happen","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1170,"y":360,"wires":[]}]
the interesting part happens in the payload of the first cron node