That file starts with a blank line then 2 lines with “OK” then the data string
OK
OK
http://wxcalgary.com/meteotemplate/api.php?
U=1520796268&T=4.3&TMX=4.3&TMN=4.3&TIN=27.8&HIN=15&H=42&P=1032.1&W=0.8&G=0.0&
B=44&R=0.0&RR=0.000&BATT=4.7&PASS=3454&SW=WD&T2=255.0&SD=1.00&LW1=0&LW2=0&L
W3=0&LW4=0