AIM 4-1-13: "ATIS information includes the time of the latest weather
sequence, ceiling, visibility, obstructions to visibility, temperature, dew
point (if available), wind direction (magnetic) ... "

AIM 4-2-10: "The three digits of bearing, course, heading, or wind direction
should always be magnetic. The word "true" must be added when it applies."

AIM 7-1-12 d3 (Note): "Wind direction broadcast over FAA radios is in
reference to magnetic north."

AIM 7-1-12 d5 Fig 7-1-8 (METAR): "WIND DIRECTION AND SPEED. Direction in
tens of degrees from true north (first three digits) ..."

PHAK Ch 11 TAF: "Forecast Wind - The wind direction and speed forecast are
given in a five-digit number group. The first three indicate the direction
of the wind in reference to true north. ..."

PHAK Ch 11 Winds Aloft: "Wind direction is always in reference to true north
...."

There's more, but this ought to be sufficient.

Regards,

Jon

"Hiro" wrote in message
...
Ok,,, so it' been known to pilots that ATIS reports are based off of
magnetic heading: AWOS, ASOS, FB WINDS (Winds Aloft) are based on true
heading. The question is, where in the FAA publication does it say
that? I looked through FAA's PHAK, AIM, and AC00-45F, but none of
them indicated anything about the heading.