21 May 11:20 am 48 36 62 N 17 10.00 FEW050 29.68 25.421 OK


21 May 11:20 am = the actual observation time was 11:20 AM local time.(MDT in this case) on May 21
48 36 62 = temp was 48 deg F, dew point (temp at which fog might occur) was 36 and relative humidity or 62%
N 17 10.00 wind from the North at 17 mph with a visibility of 10 miles.
FEW050 = a few clouds at 5000 ft above the ground
29.68 = Barometric pressure of 29.68 in of Mercury
25.421 = I don't know that one.
OK = air quality OK