Sydney radar still showing September 2010 data?

Krusty · Post by **Krusty** » Sun Jan 30, 2011 12:56

Can anyone explain why the WizTV Sydney Radar is stuck on September 2010? I assume it's because the Appin radar hasn't worked since then so is there a way to update the radar location?

prl · Post by **prl** » Sun Jan 30, 2011 14:44

Or why there's radar for Darwin, but not for Canberra (Captain's Flat radar station).

peteru · Post by **peteru** » Tue Feb 01, 2011 15:49

Darwin gets more cyclones than Canberra?

prl · Post by **prl** » Tue Feb 01, 2011 16:53

I think it's a reasonable question. Both are capitals of their respective territories, but Canberra has a population more that 2 1/2 times the size of Darwin's, which does have weather radar on WizTV. And while I don't think we ever get cyclones here, this is what neighbouring Queanbeyan looked like in December:

(http://resources2.news.com.au/images/20 ... -flood.jpg)

What I'd like to see is something along the line of what I proposed nearly two years ago:

prl wrote:Why not put the radar button on the corresponding forecast page(s)? That way, all radars could be accessible, not just those of the state capitals and the capital of the least populous mainland territory. With the buttons on the forecast pages also there'd be room for all the radar ranges, and perhaps even some of the other services like the Doppler wind and cumulative rainfall.

That was also the last time I grumbled about WizTV not carrying Canberra weather data.

peteru · Post by **peteru** » Tue Feb 01, 2011 21:08

All WizTV radar locations have been updated to use the current BOM preferred radars. The changes affected Sydney, Brisbane and Perth.

peteru · Post by **peteru** » Tue Feb 01, 2011 21:18

prl wrote:Why not put the radar button on the corresponding forecast page(s)? That way, all radars could be accessible, not just those of the state capitals and the capital of the least populous mainland territory. With the buttons on the forecast pages also there'd be room for all the radar ranges, and perhaps even some of the other services like the Doppler wind and cumulative rainfall.

The problem is that there is not enough data available from the BOM to automate this. Building and maintaining something like this would be cost prohibitive if it required manual maintenance like the current radar pages do.

prl · Post by **prl** » Tue Feb 01, 2011 21:19

peteru wrote:
prl wrote:Why not put the radar button on the corresponding forecast page(s)? That way, all radars could be accessible, not just those of the state capitals and the capital of the least populous mainland territory. With the buttons on the forecast pages also there'd be room for all the radar ranges, and perhaps even some of the other services like the Doppler wind and cumulative rainfall.
The problem is that there is not enough data available from the BOM to automate this. Building and maintaining something like this would be cost prohibitive if it required manual maintenance like the current radar pages do.

What is likely to move?

peteru · Post by **peteru** » Tue Feb 01, 2011 22:35

Forecast location != Radar location. The BOM data feed only contains forecasts. No radar data in the feed and no information to map from forecast location to radar location.

Radar images are manually hardcoded to point at well known URLs. When these change, someone has to become aware of the changes and fix the URLs.

BTW: BOM data feed classifies Canberra as a single forecast location within NSW. As far as the BOM data feed is concerned, there is no ACT.

Krusty · Post by **Krusty** » Wed Feb 02, 2011 07:14

peteru wrote:All WizTV radar locations have been updated to use the current BOM preferred radars. The changes affected Sydney, Brisbane and Perth.

Thank you peteru!

Much appreciated, I shall remember that, should it ever change in the future, I did suspect that it was a hard coded link! Thanks again & also for your reply to the other thread!!!

prl · Post by **prl** » Wed Feb 02, 2011 08:14

peteru wrote:Forecast location != Radar location. The BOM data feed only contains forecasts. No radar data in the feed and no information to map from forecast location to radar location.

Radar images are manually hardcoded to point at well known URLs. When these change, someone has to become aware of the changes and fix the URLs.

BTW: BOM data feed classifies Canberra as a single forecast location within NSW. As far as the BOM data feed is concerned, there is no ACT.

I'm aware of all that. I'm talking about how the data is presented, not how it is stored. There's nothing that says the WizTV server can't add associations to that data. In fact, you appeared to be alluding to that in your previous response, but to say that it would be too hard. Adding a level of indirection so that all WizTV references point to a place that itself contains the mechanism to extract the radar image would mean that if the URL for the radar image changed, then it would only need to be changed in one place.

As for there being no ACT in the BOM data, that may be so for the data access path you're using, but the Bureau manages to have a separate presentation of the ACT from NSW on their home page access. The ACT has a separate entry in the left sidebar for the state forecasts, a separate clickable area in the forecast map, and a separate clickable area in the map you get to via the Weather & Warnings link on the home page. Canberra is shown with the other state and mainland territory capitals in the capital cities summary in the centre of the home page.

If you follow the logical path down from any of the links to the ACT forecasts on the front page, you end up at the link http://www.bom.gov.au/act/forecasts/canberra.shtml. That's probably not the data you use directly, but it clearly shows that the BOM thinks it worthwhile to provide that logical structure layered over their internal regional classifications.

In the radar pages, though, they are classified by state and Canberra (Captains Flat) is lumped in with NSW, but the radar sites for the capitals are not distinguished. Brisbane and Adelaide are covered by more than one radar, so they're not unique.

Anyway, your post about the Sydney, Brisbane and Perth radar URLs changing reminds me that I should have a look at fixing my screenscraper that fetches BOM radar and satellite images

It no longer seems to be finding Sydney and Perth, though it's still getting both Brisbane area stations.

peteru · Post by **peteru** » Wed Feb 02, 2011 11:21

The main limitation is how the BOM licenses and provides their data feeds. WizTV can only make use of the data feeds that are licensed by the BOM for use with WizTV and must follow certain rules as to how the information is used and presented. It's not as simple as writing a screenscraper for personal use or massaging the data on the fly. The BOM data is copyrighted, so while technically it would be possible to do all sorts of cool stuff, legally you are limited as to what is permissible.

You'll just have to take my word for it, when I say that there are good reasons for things to be the way they are.

prl · Post by **prl** » Wed Feb 02, 2011 12:41

peteru wrote:... The BOM data is copyrighted, so while technically it would be possible to do all sorts of cool stuff, legally you are limited as to what is permissible.

You'll just have to take my word for it, when I say that there are good reasons for things to be the way they are.

Fair enough, but why not say that up front, instead of all the roundabout stuff about maintainability?

peteru · Post by **peteru** » Wed Feb 02, 2011 14:45

There's nothing "roundabout" with my statement about the costs involved in building and maintaining what you propose.

As with just about everything, implementing what you want just needs time and money. You give me the money and I'll take my time.

prl · Post by **prl** » Wed Feb 02, 2011 16:56

peteru wrote:There's nothing "roundabout" with my statement about the costs involved in building and maintaining what you propose.

As with just about everything, implementing what you want just needs time and money. You give me the money and I'll take my time.

That, in the end, was not the main reason you gave.