What Does TEMPO Mean in a TAF?
TEMPO means temporary fluctuations lasting less than an hour at a time during the period given. It stands for TEMPOrary fluctuations.
TEMPO in a real report
TEMPO 0520/0523 3SM TSRA
What it changes for you
TEMPO is the bad half hour inside an acceptable period. For planning it is
often the deciding line in the whole forecast.
The rule that gets misread: it is an overlay. TEMPO 2820/2824 3SM TSRA has not
said the wind changed. It has not said the rest of the period is bad. The
prevailing conditions still run underneath.
How to plan against one
If you will be there during the window, you have to be able to handle the
TEMPO conditions. Temporary says nothing about which half hour.
For an alternate, your minimums have to clear the TEMPO conditions. Treat the
prevailing forecast as the plan and the TEMPO as unlikely, and a legal
alternate turns out not to be one.
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 TEMPO mean in a TAF?
Temporary fluctuations expected to last under an hour at a time, and to cover less than half the stated period in total. It overlays the conditions already in force rather than replacing them.
Does TEMPO replace the conditions before it?
No. TEMPO overlays a temporary condition on top of whatever is already running, so anything it does not mention carries on unchanged. That is what separates it from FM, which replaces the conditions before it outright.