To use the service you need 2 things

1. A date
2. A weather station ID

For my examples i will be using the following data

Date:

May 7th 2011

Station:

WINNIPEG RICHARDSON AWOS MANITOBA
Latitude: 49°55’00.000” N   
Longitude: 97°14’00.000” W    
Elevation: 238.70 m
Climate ID: 5023226    
WMO ID: 71852   
TC ID: YWG
ID: 47407

To find the Station ID for a weather station near you you can use this google map I created.

http://maps.google.ca/maps/ms?hl=en&ie=UTF8&msa=0&msid=110896327429032700382.00048bdcb7e0dd16f3ebd&z=3

Environment Canada Station URL:

http://climate.weatheroffice.gc.ca/climateData/dailydata_e.html?timeframe=2&StationID=47407&Year=2011&Month=5&Day=01

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