Cut and pasted information for speed:
Best guess for PNO is "something" NOT OBSERVED
RMK SLP013 T01760158. Selected stations will contain SLP for Sea Level Pressure reported as the last three digits in hectoPascals (milibars) to the nearest tenth (e.g., 1001.3 is reported as SLP013).
RMK SLP013 T01760158. Also, at selected stations, the 9 character code (T01760158) breaks down the temperature and dew point to the nearest 1/10th of a degree Celsius. The "T" stands for temperature and the "0" means positive temperature. A "1" in place of the "0" stands for negative temperature. At selected stations, other temperature codes, such as10142, 20012, or 401120084, may appear to document temperatures not related to aviation.