What Does PRESFR Mean in a METAR?
PRESFR means pressure falling rapidly, often a storm or front approaching. It stands for PRESsure Falling Rapidly.
PRESFR in a real report
RMK PRESFR
What it changes for you
Two things: what is coming, and what your altimeter is doing.
Rapidly falling pressure is a system arriving. Expect the wind to pick up and change direction, and expect the ceiling and visibility that come with whatever is causing the fall.
The altimeter part is the one that bites. A setting you were given an hour ago, in air whose pressure has been dropping fast, puts you lower than your altimeter says. The old saying covers it: from high to low, look out below.
What usually comes with it
PRESFR rarely appears alone. WSHFT, FROPA and a PK WND group in the same
remarks section all describe pieces of the same event.
Related codes
Decode a report containing this code
Paste a METAR, TAF, PIREP or SIGMET into the WxDecoder decoder. Every group comes back in plain English. The raw code sits beside it, so you can check the decode rather than trust it.
Frequently asked questions
What does PRESFR mean in a METAR?
Pressure falling rapidly. The station pressure dropped at a rate of at least 0.06 inches of mercury in the 15 minutes before the observation. It usually means an approaching storm or front.
Do I need to change my altimeter setting because of PRESFR?
You need to keep it current, which you should anyway. A rapidly falling pressure means the setting you dialled in on the ground is going stale faster than usual, and flying on a high setting into a low puts you lower than indicated.