Draftiness and its aftermath

Wednesday 21 August and Thursday 22 August were a bit windy.  My weather station (in a relatively sheltered position) recorded a total wind run of 273 km  on Wednesday and 278 km on Thursday.  To put them in context they are the 6 ^th and 5 ^th longest runs I have recorded since firing up the station in February this year.  The longest run I have recorded was on 2^nd March.

It has been suggested that some explanation of the meaning of wind run would be good.  It doesn't get a mention in the BoM Glossary but other sites have the following suggestions, which between them get the idea across:

• It is a measure of the amount of wind in a period;
• It is the average wind speed per recording period multiplied by the number of recording periods; 
• It is a bit like the trip meter in a car, which measures the number of times the wheels go round and multiplies it by the circumference of the wheel telling you the distance you have traveled. For wind run is is the number of revolutions of the measuring device x the circumference of the device.

This graph compares the wind runs on the three dates.

Another way of assessing the windiness is to look at the maximum gust recorded.  This next chart shows the maximum gust x hour for the three days discussed above.

So which day was the windier?  

• Looking at the wind run chart, it is clear that 2 March wins.  This is backed up by ranking each hourly reading (1 = biggest value) with 2 March clearly having the highest average rank (1.04) and the 2  days in August being similar at 2.42 and 2.33.  
• For maximum gust the pattern is confused in the chart and only partially clarified by looking at the ranks.  2 March and 21 August are close with average ranks of 2.04 and 2.00 while 22 August is somewhat better with an average of 1.79.

An advantage of the maximum gust is that one can look at BoM data for that, while they don't show current data for runs in their free material.  Here are some numbers for the three dates (NB: as Blogger doesn't make nice with tables, this is an image so the data can't be copied as such).

In case  you wonder where Hogan Island is, wonder no more.

I scrolled West from Hogan Island, and the next non-trivial amount of land is s few km South of Buenos Aires - so the roaring 40s are a little North of their range.

This windiness leads to an amount of damage to trees etc so it was good to see a team of arborists out tidying things up this morning.  (They had been out and about yesterday as well.)

Well done that team!  Not everyone was feeling that energetic!