# How do I get the forecast from OpenWeatherMap?

**URL:** <https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028>\
**Category:** General\
**Created:** [2 September 2019 11:50 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028 "2019-09-02T11:50:20Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![SteveMann](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/stevemann/32/3810_2.png) [@SteveMann](https://discourse.nodered.org/u/SteveMann)\
**Post date:** [2 September 2019 11:50 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028/1 "2019-09-02T11:50:20Z")

</div>

I have openweathermap generating the current weather once a minute. That part works just fine. However, I would like to know if rain is in the forecast so that I can turn off my lawn sprinklers. I've tried creating a second OWM node and new API key for that node, and all I get is "invalid API key".

I tried changing the currently working node: "Current weather for.." to "5-Day forecast for..", but I can't find where in the JSON response I would find out if it's going to rain or not. And yes, I've read the API docs.

Any assistance would be greatly appreciated.

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<div class="post-metadata">

**Author:** ![afelix](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/afelix/32/9743_2.png) [@afelix](https://discourse.nodered.org/u/afelix)\
**Post date:** [2 September 2019 12:25 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028/2 "2019-09-02T12:25:16Z")

</div>

It appears that probability for precipitation is not included in the JSON API ☹ So it looks like the best you can get is by hooking your setup to `weather.main` and look for the text values such as `"Rain"`, `"Drizzle"` and `"Snow"`. Furthermore, you can use `msg.data` to page through the full API response, which gives the amount of precipitation already fallen in the last hour if needed

[https://openweathermap.org/current#current\_JSON](https://openweathermap.org/current#current_JSON)

However, it appears the XML API _does_ have some information about precipitation available, which in my opinion is odd that they didn't make those available in the JSON api as well.

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<div class="post-metadata">

**Author:** ![SteveMann](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/stevemann/32/3810_2.png) [@SteveMann](https://discourse.nodered.org/u/SteveMann)\
**Post date:** [2 September 2019 13:50 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028/3 "2019-09-02T13:50:19Z")

</div>

I think I found it..

```auto
      {  
         "dt":1567447200,
         "main":{  
            "temp":20.16,
            "temp_min":19.28,
            "temp_max":20.16,
            "pressure":1016.58,
            "sea_level":1016.58,
            "grnd_level":1005.97,
            "humidity":84,
            "temp_kf":0.88
         },
         "weather":[  
            {  
               "id":500,
               "main":"Rain",
               "description":"light rain",
               "icon":"10d"
            }
         ],
         "clouds":{  
            "all":100
         },
         "wind":{  
            "speed":2.79,
            "deg":170.433
         },
         "rain":{  
            "3h":0.5
         },
         "sys":{  
            "pod":"d"
         },
         "dt_txt":"2019-09-02 18:00:00"
      },

```

This is the forecast for 5 hours from now, and it does show rain. Do you have any clue what this means?

```auto
 "rain":{  
            "3h":0.5
         }

```

Also, do you have any clue which object in an array of ten objects within an array of 40 objects should I be looking at? And there's two of these arrays of 40 objects of ten objects. I get dizzy trying to understand basic objects, so you can see why this has me puzzled.

```auto
9/2/2019, 9:33:57 AMnode: 5cd765d7.01a35c
msg : Object
 object
 topic: ""
 payload: array[40]
  [0 … 9]
    0: object
    1: object
    2: object
    3: object
    4: object
    5: object
    6: object
    7: object
    8: object
    9: object
  [10 … 19]
  [20 … 29]
  [30 … 39]
 _msgid: "136a2f4.0f761d1"
 location: object
 data: object
   cod: "200"
   message: 0.0111
   cnt: 40
   list: array[40]
   city: object
 title: "5 day Forecast"

```

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<div class="post-metadata">

**Author:** ![ukmoose](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ukmoose/32/13_2.png) [@ukmoose](https://discourse.nodered.org/u/ukmoose)\
**Post date:** [2 September 2019 13:52 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028/4 "2019-09-02T13:52:50Z")

</div>

Write the entire JSON output to a file and then open it in a text editor that can format/colour JSON.

Far easier to search for terms and see the over all structure.

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<div class="post-metadata">

**Author:** ![afelix](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/afelix/32/9743_2.png) [@afelix](https://discourse.nodered.org/u/afelix)\
**Post date:** [2 September 2019 14:04 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028/5 "2019-09-02T14:04:35Z")

</div>

This is the 5 day/3 hour forecast right? That means each of the items in the payload array contains 1 forecast every 3 hours for a period of 5 days. That's 8 a day, times 5 is 40 items total. Each of the objects has a timestamp for when it's going to be, I don't know from mind if the one nearest is shown first or last, but I can imagine in position 0. Each of those objects will have the same kind of formatting. Meaning you can use a JSONAta to get out what you want. I'm bad at writing those, but I know others on this forum are genius at that.

> [@SteveMann](#):
>
> This is the forecast for 5 hours from now, and it does show rain. Do you have any clue what this means?

I think this depends on what the API docs say for it. Could be probability, like 50% chance for rain... can be 0.5mm of rainfall. Look it up in the OWM api docs, that's all I can advise. I use a completely different API for my own forecasting needs, so I'm not able to help you there without looking up those things in the same place myself too.

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<div class="post-metadata">

**Author:** ![SteveMann](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/stevemann/32/3810_2.png) [@SteveMann](https://discourse.nodered.org/u/SteveMann)\
**Post date:** [2 September 2019 14:19 UTC](https://discourse.nodered.org/t/how-do-i-get-the-forecast-from-openweathermap/15028/6 "2019-09-02T14:19:26Z")

</div>

Yes, from the 5 day/3 hour forecast. But there is no current weather, (but a second node with "Current Weather" selected does work with the same API key).

The objects are not formatted the same. Object 0 in array 0 contains no rain object. The rest do.

```auto
9/2/2019, 10:05:10 AMnode: d39452b1.78f4a
msg.payload : array[40]
  array[40]
  [0 … 9]
    0: object
      dt: 1567436400
      main: object
      weather: array[1]
      clouds: object
      wind: object
      sys: object
      dt_txt: "2019-09-02 15:00:00"
    1: object
      dt: 1567447200
      main: object
      weather: array[1]
      clouds: object
      wind: object
      rain: object
        3h: 0.5
      sys: object
      dt_txt: "2019-09-02 18:00:00"
    2: object
      dt: 1567458000
      main: object
      weather: array[1]
      clouds: object
      wind: object
      rain: object
        3h: 2.188
      sys: object
      dt_txt: "2019-09-02 21:00:00"
   3: object
      dt: 1567468800
      main: object
      weather: array[1]
      clouds: object
      wind: object
      rain: object
        3h: 10.687
      sys: object
      dt_txt: "2019-09-03 00:00:00"

```

I was guessing that the rain object shows the accumulated rain over three hours. But if this were so, I should have a boat handy in the third object.