ACCESS data is green and GFS data is blue where applicable. The total cloud lines are also bold and clearly visible.
Top level clouds are purple, mid level clouds are brown and low level clouds are red.
Both short term (Days 1-3) and long term (Days 3-5) meteograms are now updated and live.
You can also use the two new buttons right under the meteogram graphs to switch between (Days 1-3) and (Days 3-5) or you can just swipe the meteogram picture horizontally.
Another useful blend is a combination of Total Cloud with Pressure/Rainfall overlay. It will highlight potential precipitation nicely in the areas of total cloud coverage. Many combinations of blends are available for all models so feel free to experiment.
Near the intersection of Burke/Toorak rds and the Sth Eastern feeway
Andrew
In the map sequences, this morning in NSW over the blue mountains range and central tablelands, you can see cloud areas with defined, sharp edges that do not move with the other cloud layers. It is very likely these are low level fog layers. Blinking between the total cloud map and the low level cloud map reveals the difference (mid and high level layers are empty).
This is further confirmed by the satellite loop aus_vis in the same time period. Here's a loop showing fog this morning in NSW over the range and central tablelands.
The fog can be easily identified as it is fairly stationary in contrast of all other cloud layers. It also dissipates in situ and does not drift dramatically. The shape of the fog is also consistent with the contour of the valleys and topography in the range.
So if you happen to see a 100% cover in your meteogram or total map cloud and it doesn't add up to the sum of all the other layers, then your probability of fog will be increased.
You can now check the progress of both downloading the new data from the BoM and the local processing of the data generating the pictures for both Maps and Meteograms. Click on the icons looping arrows or downward arrow, respectively update and download, to view the starting time, time elapsed and a progress pie chart for each process.
Looking at the ACCESS-R Meteogram What is the relationship between the %ages for Low, Middle and High cloud cover and the Total cloud cover figure? ie. the three cloud cover columns (low, middle and high) often don't add up to the Total cloud cover %, why is that? Eg. Tues night in Canberra is showing zero% Low, Middle and High cloud up to 01:00 but 72% Total cloud from 22:00..?
Looking at the ACCESS-R Meteogram What is the relationship between the %ages for Low, Middle and High cloud cover and the Total cloud cover figure? ie. the three cloud cover columns (low, middle and high) often don't add up to the Total cloud cover %, why is that? Eg. Tues night in Canberra is showing zero% Low, Middle and High cloud up to 01:00 but 72% Total cloud from 22:00..?
Mike
This situation has been observed a number of times already and is most likely associated with the recent upgrade to the ACCESS-R model. I believe this anomaly is due to the model trying to predict fog conditions and somehow counting this value towards the total cloud cover. It appears the model is not correctly handling some fog/low cloud conditions. This situation is currently under investigation and will be clarified once the updated model documentation is released by the Bureau of Meteorology.
Looking at the ACCESS-R Meteogram What is the relationship between the %ages for Low, Middle and High cloud cover and the Total cloud cover figure? ie. the three cloud cover columns (low, middle and high) often don't add up to the Total cloud cover %, why is that? Eg. Tues night in Canberra is showing zero% Low, Middle and High cloud up to 01:00 but 72% Total cloud from 22:00..?
Mike
Don't think too hard about the exact numbers would be my advice. In the model's complex view of the world, the high cloud may be in the same place as the low cloud therefore it doesn't add anything to the total cloud cover.
If the model sees the high cloud in only the places where the low cloud is not, then the two figures might add together. But in general that will not be the case.
How should one interpret the predictions when the two lines (GFS & ACCESS) on the Meteogram diverge and completely disagree...?
Mike
Sorry I didn't reply to this earlier but important to note this.. the Meteograms are a very quick and convenient way to grab a cloud forecast but you really must look at the maps if you want to understand the forecast and the differences.
One model (or just one model run) might have an area of low cloud stopping 10km short of your location, and another might have it directly over you. Such small differences are just random fluctuations (noise) in the model output and rarely indicative of real weather, but they will show as a big divergence when viewed as a point forecast via the Meteogram.
A quick look at the map over a few time steps will help separate model signal from noise . The actual weather that arrives might be something different again.
But yes, if the map shows a big and consistent difference between GFS and ACCESS in the 1-3 day forecast, then it's maybe 70-30 odds for ACCESS better (wild indicative guess). Once you're looking 3-5 days ahead, then it's 50-50 either way.
The forecasts maps can now be animated. There is a play/stop button on the top right of the map viewport. Press to play, press again to stop. Or you can use the side menu button "MAP Loop/MAP Image" identical to the satellite page.
The time increment for the playback is currently 3h. Swiping the map horizontally will stop the playback and the time will revert automatically to your previously selected time.
The map touch events are unchanged while playing so you can change anything on the fly: region (AUS, SEAUS, QLD, etc...), model (GFS/ACCESS) , map type (Cloud, Fog, Wind, etc...) seamlessly. If you plan to lock and overlay maps it will play the selected blend.
The frame rate will greatly depend on your graphic hardware. It was tested on various devices and proved to be very fast on any desktop PC and recent tablets or mobile phones with no issues whatsoever, reasonably fast to a little slow on much older devices. If your display is jittery on old mobile phones pressing the map button in the menu will resync the loop in most cases.
Blended maps will be more taxing on your hardware. In any case CFN will adjust the fps automatically if your graphic hardware cannot sustain the desired frame rate.
You'll find that the CFN navigation menus were slightly modified in the Meteogram and Satellite pages. The side menus are now shorter and less cluttered. All the external link buttons have been grouped under two new buttons called "EXTERNAL RESOURCES".
All the links to external resources will show up in a popup window along with any other content.
Under the meteogram page we added a link to the OzForecast ADFD meteogram.
Quote:
This presents a graphical view of the forecast for your location based on data from the Australian Digital Forecast Database (ADFD) predictions issued by the Australian Bureau of Meteorology. The red line shows the forecast temperature. The grey arrows show the predicted wind speed and direction. The rain forecast down the bottom displays the 50% probability and 25% probability daily rainfall totals, while the blue columns up the top show the possible 3-hourly rainfall distribution, which is only available for the first two days. The greyscale across the top of the chart show the expected sky cloud cover.
I found it really really good , in accuracy as much as can be expected, in simplicity of the presented data, and in no-claim ‘just present data’ concept –had liked that from the start.
I prefer no cookies. Prefer it not to default to my location; it's really annoying esp. when I'd be observing somewhere else.
Instead I wish it would let me set multiple bookmarks of locations or displays or refinements, so that only one click would get me to location 1 of the particular display I like. Another occasion or on the same weekend, just one click would get me to location 2 etc. Then I’d make a decision.
About the ‘seeing’ I’d prefer it displayed; I don’t want to have to fiddle with overlays or anything.
Being a firm fan, I knew immediately what cfn was but others have a valid point. On the other hand it could be your way of familiarising users with cfn such that soon we’d be saying cfn and forgetting what it stands for!
Not sure how useful this would be: somewhere that shows a trend plot of the actuals? (Could be of academic interest to also see actuals vs forecasts but no matter.)
In your development for mobile devices please remember us big-screen lap-toppers (we're mobile too but), and Maccas.
THANK YOU cfn. You’re doing a great service to the astronomy community.
Instead I wish it would let me set multiple bookmarks of locations or displays or refinements, so that only one click would get me to location 1 of the particular display I like. Another occasion or on the same weekend, just one click would get me to location 2 etc. Then I’d make a decision.
You mean the ability to save locations in a "favorite" list? That's interesting. Will look into this when implementing login and user profiles.
Quote:
Originally Posted by Sol-Skysailor
About the ‘seeing’ I’d prefer it displayed; I don’t want to have to fiddle with overlays or anything.
Unfortunately there is no way at this stage to have a seeing index. The next best thing is blinking the wind and jetstream maps. That's how the map overlays came to be. You can view both in one screen. Until we have something better that's all we can do.
Quote:
Originally Posted by Sol-Skysailor
Being a firm fan, I knew immediately what cfn was but others have a valid point. On the other hand it could be your way of familiarising users with cfn such that soon we’d be saying cfn and forgetting what it stands for!
CFN is easier to type than Cloud Free Night.
Quote:
Originally Posted by Sol-Skysailor
Not sure how useful this would be: somewhere that shows a trend plot of the actuals? (Could be of academic interest to also see actuals vs forecasts but no matter.)
We don't keep any history of past data. We currently have limited resources and have to be smart about it. We generate over 4GB of images every 24h. It is a lot of processing and the server is idle maybe 5% of the time each day. And that's not counting any users browsing the site. So maybe in future if we have room to expand and more funds.
Quote:
Originally Posted by Sol-Skysailor
In your development for mobile devices please remember us big-screen lap-toppers (we're mobile too but), and Maccas.
THANK YOU cfn. You’re doing a great service to the astronomy community.
Sol
Desktop PCs are the easy part to develop for but we'll never leave anybody behind whatever device they use to access CFN.
I found it really really good , in accuracy as much as can be expected, in simplicity of the presented data, and in no-claim ‘just present data’ concept –had liked that from the start.
Hence the lack of seeing index. We don't manufacture an index. We present raw data. The user makes up his mind and own forecast based on this data. That's what CFN is about. Presenting data, not delivering a weather forecast.
You mean the ability to save locations in a "favorite" list? That's interesting. Will look into this when implementing login and user profiles.
Hi cfn, I was meaning simple browser bookmarks that I would view say 2-3 tabs for my cfn favourites (could then look back and forth without needing a reload when in a bad internet area).
Hoping not to have to login, it’d be a big disincentive for me. But of course it’s up to what you need to do.
Also, top marks for seeking inputs from users and actually listening. Good work.
Hi cfn, I was meaning simple browser bookmarks that I would view say 2-3 tabs for my cfn favourites (could then look back and forth without needing a reload when in a bad internet area).
You can already do this by bookmarking any existing meteogram location and save it in your favourites or add it to your home screen on your mobile device.
Quote:
Originally Posted by Sol-Skysailor
Hoping not to have to login, it’d be a big disincentive for me. But of course it’s up to what you need to do.
Customizing CFN for a user means the site needs to know who's using it. The easiest way is to authenticate a user. We're working into automating this while keeping it secure. We don't want to make this harder than it needs to be. But each user having a profile on CFN means they could start building their list of sites and do what you've mentioned earlier.
Hi cfn, I was meaning simple browser bookmarks that I would view say 2-3 tabs for my cfn favourites (could then look back and forth without needing a reload when in a bad internet area).
Hoping not to have to login, it’d be a big disincentive for me. But of course it’s up to what you need to do.
Also, top marks for seeking inputs from users and actually listening. Good work.
Regards
Sol
You can already do this? Here's my bookmarked URL for my place: