TAF help

[Captain]

Anyone here know the ceiling altitude structure for TAFs?

Like I've seen 007 broken but never 027 bkn. Seems like its hundred foot increments to around 1 thousand and then 500 foot increments. But I can't find it listed anywhere.

Thanks in advance.

 

[MAKG1]

It's clearly not that simple. The current TAF for Oakland has XXX012:

KOAK 241137Z 2412/2518 34003KT P6SM OVC015
[FONT=Monospace,Courier][SIZE=+1] FM241700 29007KT P6SM SCT010
FM242200 28014KT P6SM FEW012
FM250300 29009KT P6SM SCT012
FM250700 29005KT P6SM BKN012
[/SIZE][/FONT]

 

[Captain]

It's typically based on the VLIFR, LIFR, IFR, MVFR and VFR flight categories as well as the IFR alternate requirements and approach minimums. There's not much of a difference between OVC012 and OVC015. So you'll likely see OVC015. Same with BKN027 and BKN025. BKN025 will be forecast.

Thanks. Do you know of an official table that breaks it down and shows how rounding will be done or is it up to the observer?