PRESFR
Indicates that the atmospheric pressure has been falling at a rate of at least 0.06 inches of mercury (2.03 hPa) per hour at the time of observation. Rapidly falling pressure is a significant weather indicator, often preceding the arrival of strong low pressure systems, fronts, or severe weather.
RMK PRESFR
RMK AO2 PRESFR
RMK PRESFR SLP968
PRESFR stands for "Pressure Falling Rapidly" in the remarks section of a METAR report. Indicates that the atmospheric pressure has been falling at a rate of at least 0.06 inches of mercury (2.03 hPa) per hour at the time of observation. Rapidly falling pressure is a significant weather indicator, often preceding the arrival of strong low pressure systems, fronts, or severe weather.
PRESFR 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: "RMK PRESFR". This appears in the remarks section and indicates pressure falling rapidly information as part of the weather observation.