P
Reports the amount of precipitation that has fallen in the past hour, in hundredths of an inch. The value follows the P indicator as a four-digit number. For example, P0012 means 0.12 inches of precipitation fell in the last hour. P0000 indicates a trace of precipitation (less than 0.005 inches).
P0012
P0000
P0156
P stands for "Hourly Precipitation" in the remarks section of a METAR report. Reports the amount of precipitation that has fallen in the past hour, in hundredths of an inch. The value follows the P indicator as a four-digit number. For example, P0012 means 0.12 inches of precipitation fell in the last hour. P0000 indicates a trace of precipitation (less than 0.005 inches).
P appears in the remarks (RMK) section at the end of a METAR observation. The remarks section follows the main body of the METAR and provides additional details about the observation that don't fit into the standard coded format.
Here is an example: "P0012". This appears in the remarks section and indicates hourly precipitation information as part of the weather observation.