A METAR reports: KSFO 121853Z 28012G20KT 10SM FEW015 SCT035 18/12 A2992. What is the wind condition?

The wind group 28012G20KT decomposes into three parts: 280 is the direction the wind is coming from, 012 is the sustained speed, and G20 is the peak gust, all in knots. Two details separate a confident answer from a guess. First, wind direction is always the direction the wind blows from, not toward. Second, winds in a written METAR are referenced to true north, while winds spoken over the radio by a tower or ATIS are referenced to magnetic north — a distinction that exists because charts are drawn to true and runways are numbered to magnetic. For a remote pilot the gust value drives the decision: a 12-knot sustained wind is routine for most airframes, while 20-knot gusts can exceed the margin a small aircraft has left for position holding.

280 gives a wind from 280 degrees referenced to true north because this is a written METAR, 12 knots is the sustained speed, and G20 marks gusts to 20 knots. All three elements read directly off the group in fixed positions.

METAR wind groups are written as dddffGffKT. Written observations reference true north; spoken ATIS and tower winds reference magnetic north. Gusts are reported when the peak exceeds the sustained speed by 10 knots or more.

Written Is True, Spoken Is Magnetic. If you read it on a page, it points at true north; if you hear it on the radio, it lines up with the runway numbers.

Check the gust value against your aircraft's published wind limit, not the sustained speed. Gusts are what exceed the margin, and they are what the exam expects you to notice.

• •Applying magnetic reference to a written METAR
• •Transposing the direction and speed fields
• •Planning to the sustained wind and ignoring the gust value