Category Archives: BoM Australia

Weather Bureau for Australia

Perth heading for coldest September since at least 1906

Chris Gillham in Perth has been monitoring mean daily temperatures at Perth BoM sites and says Perth Airport 9021 is a shoo-in to have the coldest September mean since opening in 1944. Perth Metro 9225 in Mount Lawley has only been open from Jan 1994 replaced Perth Regional Office 9034 which commenced 1897 and underwent various moves before ending up in East Perth. Progress with temperature updates can be checked at AWN or the BoM.
Chris has a page discussing the history of various Perth weather stations since 1897. I will update as the final numbers are available and hope to include other Perth region sites such as Pearce – Jandakot – Medina etc It is amazing we can have a month like this in the teeth of the vast Perth urban heat island.

BoM max temperature Outlook for September heading for fails

A large percentage of Australia was predicted to have hotter than normal days this month –

as Sep counts down keep a watch on how different areas are trending.
Using the easy to access AWN monthly data it looks as though the following areas will need a late Sep heatwave to avoid the Outlook failing.
For example Tasmania, Adelaide, Ceduna, Alice Springs, Perth, Kalgoorlie region, Giles region, Kimberley, Cape York.
You can also compare with weekly max temp anomalies through this month – which show substantial green or neutral areas. You should be able to see maps for the weeks ending 6th, 13th and 20th Sep.
Here are the 4 weekly max anomaly maps starting 6th Sep 16

13th Sep 16

20th Sep 16

27th Sep 16

Perth dam catchments rainfall – how much is that?

It is obvious that BoM and Water Corporation rain stations are low down in catchments near the various dams –

convenient near roads and easy for staff to monitor. Click on Select Using Map – Large areas of the catchments are not monitored by BoM rainfall stations. In 1997 this contour map showed annual average rain for SW WA – the rain numbers would have been heavily influenced by pre 1975 higher level rainfall. It would be helpful if the WA Govt or BoM could redo the map using post-1975 rainfall – which is vastly more relevant to water supply issues than pining after pre-1975 numbers.
The WA Dept of Food & Agriculture have a www site for their own network of weather stations – which in many cases also report to the BoM pages – for example the daily rain maps.
Last week I noticed that the DAFWA station Glen Eagle near the Albany Highway between the Canning and Wungong catchments has recorded the stunning total of 1280mm for the year to date.

Perhaps it is at a higher altitude – will try and find out. GE only commenced in August 2015 – I assume DAFWA checks the calibration of their instruments.
Here is my table of catchment stations with 2016 rain totals updated through August.

The zeros & blanks need urgent attention from the BoM and some monthly totals from Water Corp need examination.
The WA Dept of Water has a large network of stations in the catchments but most seem to be discontinued. Here is a map of their stations – Set Site Category to Meteorological.

I checked a string along the Brookton Highway and none was current – it is time consuming to check. Who knows what useful data they may have. We need all data public to audit and produce a better record of catchment rain.

Example of error in Bureau of Meteorology rain data

On the weekend I noticed this error in the BoM rain map –

I thought come Monday they will correct this to 9.27mm. Here we are Tuesday and no such luck, the error has gone into their daily rain numbers – presumably to be discovered in checks at a later date, weeks months away. It has also gone into 3rd party sites like AWN

there could be others. It puzzles me that an error as gross as this lives on for 3 days – surely a little robot algorithm could flag outliers way less than this. I thought it was topical in view of my call for an audit of Perth dam catchments rain data.

Perth dams rain data is in need of an audit

Just ran an update as at 31 July – several Water Corporation stations look suspect – several BoM stations are out of date by months. My spreadsheet showing audit required.Source of BoM data and map – for a years daily data enter the 6 digit BoM station ID alongside Station number then click the Get Data button. Map showing dams and localities. BoM map with their sites and dams visible.
In May I reported – West Australian Govt Water Corporation fails to record March 2016 rain at several dams

Sydney hottest April day last Wednesday only happened at Observatory Hill

The centre of our largest urban heat island reached 34.2 on 6 Apr 2016 topping 33.9 from 5 Apr 1986.
Other stations I have checked that were open in 1986 were all hotter in April 1986.
Sydney Airport 34.7 on 6 Apr 2016 but 35.7 on 4 Apr 1986
Bankstown AP 35.8 on 6 Apr 2016 but 36.9 on 4 Apr 1986
Parramatta Nth 35.2 on 6 Apr 2016 but 37 on 4 Apr 1986
Richmond RAAF(067105) 36.6 on 6 Apr 2016 but Richmond RAAF(067033) 38.2 on 4 Apr 1986
The ABC TV weather news was beating up Penrith but that station did not open until 1995 and there seems to be no other Penrith station – tough – what liars.

Looking at the state I have checked Goulburn, Condobolin, Cobar, Bourke – the first 3 were all hotter in Apr 1986. Bourke Post Office was hotter 3 times between 1906 and 1922. So just now I can not find that 6 April made a record hot day anywhere in NSW except Sydney Obs Hill – any suggestions? This would be remarkable.