Saving Weather Stations to a Shapefile with Python

The National Weather Service offers several XML data feeds related to weather conditions. In this tutorial we will use the list of all national observation stations to create a shapefile of Washington stations with Python.

def createXMLfileFromURL(strURL,strOutFilePath):

 #Open url and read
 res = urllib2.urlopen(strURL)
 data = res.read()
 
 #Write data to file
 writer = open(strOutFilePath,'w')
 writer.write(data)
 writer.close()

if __name__=='__main__':

 #Grab the XML feed and write it to a file
 noaaIndexXML = '/home/gregcorradini/XMLfeeds/indexNOAAII.xml'
 createXMLfileFromURL('http://www.weather.gov/xml/current_obs/index.XML',noaaIndexXML)

 #Use ElementTree to walk XML for 'station'
 root= (etree.parse(noaaIndexXML)).getroot()
 listStations = root.findall('station')

 #Findall WA stations in XML document
 waStations = [i for i in listStations if i.findall('state')[0].text == 'WA']

 #Create a dictionary for each station
 dictWa = {}
 for i in waStations:
  #Notice we are using the lat/lng values to create a geom.Point
  dictWa[i.findall('station_id')[0].text] = {'the_geom':geom.Point(float(i.findall('longitude')[0].text),float(i.findall('latitude')[0].text)),'station_id':i.findall('station_id')[0].text,'lat':float(i.findall('latitude')[0].text), 'lng':float(i.findall('longitude')[0].text), 'xml_url': i.findall('xml_url')[0].text}

 #Create a schema for weather stations
 staSchema = schema.Schema('wa_stations_notemp',[('the_geom',geom.Point,Projection('epsg:4326')),('station_id',str),('lat',float),('lng',float),('xml_url',str)])

 #Get a workspace
 ws = Directory('/home/gregcorradini/GeoTools/geoscript_wrk/isolines/data/US_shapefiles/')

 #Create a stations shapefile with our schema
 staLayer = ws.create('wa_stations_notemp',schema=staSchema)

 #Create a feature for each station value
 counter = 1
 for key in dictWa.keys():
  staFeature = staLayer.schema.feature(dictWa[key],str(counter))
  staLayer.add(staFeature)
  counter += counter