Question:
When I see the temperature of the hour on a particular site, does that mean the average for the time period since the last reported data point, or is it the instant temperature at that exact time?
Answer:
Hourly temps are the "near instantaneous" readings at the time of the hourly report (i.e., minute xx:53 at Metro Airport).
Wind data (speed & direction) are typically based on the average over a 2-minute period ending at the observation time (i.e., xx:53). If wind directions vary by something like 60 degrees or more over the 2-minutes, the direction is termed "variable."
The hourly "gust" is the maximum 3- or 5-second average wind recorded during the 2-minute period. The "gust" direction is assumed to be the same as the direction of the 2-minute wind. Gusts are reported if/when the gust tops something like 14-15 knots.
There are some other options: in each hourly report (called a METAR report), there can be a "PEAK WIND" included in the "REMARKS" comments.
The "PEAK WIND" is really the PEAK gust that occurred since the last METAR report, and includes, speed, direction and time-of-occurrence.
In fact, there are intermediate METAR reports, called SPECIALS, that can be issued between the hourly reports.
Hope this helps.
Jay Grymes
Chief Meteorologist
WAFB Storm Team
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