Fetches the mean average temperature and the mean observed average temperature

fetch.py

body = {
    'sid': 'DENthr',
    'sdate': '2018-01-01',
    'edate': '2018-06-31',
    'output': 'json', # csv or json
    'elems': [
        {
          "name": "avgt",
          "interval": "mly",
          "duration": "mly",
          "reduce": "mean",
          "normal": "departure"
        },
        {
          "name": "avgt",
          "interval": "mly",
          "duration": "mly",
          "reduce": "mean",
          "normal": "1"
        },
    ]
}

# Use your standard URLEncode stuff here
encoded_body = json.dumps(body)

url = 'http://data.rcc-acis.org/StnData'
body = {'params': encoded_body}

# Be aware that the requests library automatically URL encodes the 
# value of the data parameter, so you might have to play with this 
# to get it working the way you want. The really nasty part about this
# API is that you have to URL encode the value of your "params" first,
# then it gets encoded again as the post body
request = requests.post(url, data=body)
response = request.text

print(response)

fetch.sh

curl 'https://data.rcc-acis.org/StnData' \
-H 'Content-Type: application/x-www-form-urlencoded; charset=UTF-8' \
-H 'Accept: application/json, text/javascript, */*; q=0.01' \
--data 'output=json&params=%7B%22sid%22%3A%22DENthr%22%2C%22sdate%22%3A%222018-01-01%22%2C%22edate%22%3A%222018-06-30%22%2C%22elems%22%3A%5B%7B%22name%22%3A%22avgt%22%2C%22interval%22%3A%22mly%22%2C%22reduce%22%3A%22mean%22%2C%22normal%22%3A%22departure%22%7D%2C%7B%22name%22%3A%22avgt%22%2C%22interval%22%3A%22mly%22%2C%22reduce%22%3A%22mean%22%2C%22normal%22%3A%221%22%7D%5D%7D'

response.json

{
  "meta":{
    "state": "CO", 
    "sids": ["DENthr 9"], 
    "uid": 32706, 
    "name": "Denver Area"
  },
  "data":[
    ["2018-01","3.95","30.70"],
    ["2018-02","-2.61","32.50"],
    ["2018-03","2.28","40.40"],
    ["2018-04","0.42","47.40"],
    ["2018-05","4.34","57.10"],
    ["2018-06","5.03","67.40"]
  ]
}

I added the bash script to cURL it, but be aware it requires URL encoding on the JSON you supply as the argument to the params parameter.