24 Hour Freeze Warning
This checks openweathermap.org for the low temperatures for the next 24 hours and provides an alert to Home Assistant if outside temperature is or will go below freezing. Imperial (Farenheit) temperature is used and US Zip code is used, but the flow can easily be edited to long/latitude. See Forecast Api documentation for options. Make sure you update the "Get 5 Day Forecast" node to edit the url to put in your zip and token "http://api.openweathermap.org/data/2.5/forecast?zip=zip=[REPLACE_WITH_YOUR_ZIP_AND_COUNTRY_ID]&appid=[REPLACE_WITH_YOUR_API_KEY]&units=imperial" (api token you can get free at Openweathermap.org). The message states the first time the temperature dips below freezing and also states the lowest temperature in next 24 hours.
Example screenshot of Windows Desktop notification using Homeassistant Taskbar Menu:
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Temperature will continue to be below freezing in next 24 hours and will be \" + msg.messages.future24Hours.twentyFourHourLow + \"\\u00B0F on \" + msg.messages.future24Hours.twentyFourHourLowTime;\n \n } else {\n msg.payload.data.message = \"Freeze Warning: It is currently \" + msg.messages.currentLow + \"\\u00B0F.\";\n \n }\n return msg; \n\n}\n\nif (!isEmpty(msg.messages.future24Hours.twentyFourHourLow)) {\n msg.payload.data.message = \"Freeze Warning: It will be \" + msg.messages.future24Hours.firstFreezeTemp + \"\\u00B0F on \" + msg.messages.future24Hours.firstFreezeTime + \", getting down to \" + msg.messages.future24Hours.twentyFourHourLow + \"\\u00B0F on \" + msg.messages.future24Hours.twentyFourHourLowTime;\n return msg; \n}\n\n\nreturn msg; \n\nfunction isEmpty(str) {\n return (!str || str.length === 0 );\n}\n\n\nfunction formatTime(dateString) {\n \nvar options = {\n\tweekday: 'long',\n month: \"2-digit\",\n day: 'numeric',\n year: '2-digit',\n hour: 'numeric',\n minute: 'numeric',\n hour12: true\n};\ndateString = dateString.split(\" \").join(\"-\").split(\":\").join(\"-\").split(\"-\");\n\nvar date = new Date(dateString[0], dateString[1] - 1, dateString[2],dateString[3],dateString[4]);\n\nreturn date.toLocaleString('en-US', options);\n}\n","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":950,"y":1180,"wires":[["c632ba8fb423ed30","32f47ba8af8bbd3c"]]},{"id":"c632ba8fb423ed30","type":"switch","z":"9f91b407.d238f8","name":"","property":"payload.data.message","propertyType":"msg","rules":[{"t":"nempty"},{"t":"eq","v":"","vt":"str"}],"checkall":"true","repair":false,"outputs":2,"x":810,"y":1280,"wires":[["2e6f4746c075230f","696430b5064f374e"],[]]},{"id":"2e6f4746c075230f","type":"api-call-service","z":"9f91b407.d238f8","name":"Notify Home Assistant","server":"","version":1,"debugenabled":false,"service_domain":"notify","service":"persistent_notification","entityId":"","data":"{\"message\":\"\"}","dataType":"json","mergecontext":"","output_location":"payload","output_location_type":"none","mustacheAltTags":false,"x":1060,"y":1280,"wires":[[]]},{"id":"696430b5064f374e","type":"debug","z":"9f91b407.d238f8","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload.data.message","targetType":"msg","statusVal":"","statusType":"auto","x":1040,"y":1340,"wires":[]}]
