I signed up for the Wunderground API Key and needed a script to grab the extended forecast.
#!/usr/bin/env python
import urllib2
import json
wurl = urllib2.urlopen("http://api.wunderground.com/api/<your-key-here>/forecast/q/TX/KSAT.json")
json_string = wurl.read()
parsed_json = json.loads(json_string)
for data in parsed_json['forecast']['simpleforecast']['forecastday']:
print data['date']['weekday'] + ':'
print data['conditions']
print "Highs:", data['high']['fahrenheit'], "Lows:", data['low']['fahrenheit'], "\n", data['pop'], "% Chance of rain \n"
wurl.close()