[ale] [OT] need live weather radar display

Alex Carver agcarver+ale at acarver.net
Tue Apr 2 19:40:27 EDT 2013


On 4/2/2013 16:02, Ron Frazier (ALE) wrote:
> Hi all,
>
> The following is something I've been periodically searching for for a
> few years.  I need a firefox plugin or website or even a windows and
> linux native app that can display live weather radar on my screen.  It
> must have the following features.
>
> * capable of sitting off in a corner of the screen in a 2" x 2" to 4" x
> 4" window
> * shows current radar when activated and the time the data is from
> * location of the active radar data source can be chosen, unless it
> shows multiple ones
> * map should be zoomable and scrollable
> * street maps and city names should show up under the radar image
> * radar image transparency should be controllable
> * preferably, should reestablish it's settings and location and size
> when restarted
> * I do not need radar animation, just the current status.
> * MUST! auto update every few minutes when the weather service issues
> new radar data, no less often than every 15 minutes, more often if possible
>
> Essentially, I want a little box on my screen to always look as if I'd
> tuned to the weather radar channel on tv.  Trying to go to the tv
> station's website and put that in a window doesn't work too well
> either.  I can go to weather.com and display a map and shrink it, but it
> doesn't look too great, requires me to re establish the window when I
> restart firefox, and doesn't auto update.
>
> I just want to be able to glance at this little window at any time and
> see what's coming my way.  I thought about buying one of those $ 50
> android tablets at big lots just to run a radar app, but that seems like
> overkill.
>
> As I said, I've been searching for something like this for a while and
> haven't found it.
>
> Any help is greatly appreciated.

Radar data isn't updated very fast in mild weather.  In severe weather, 
the volume scan speed is increased and the number of slices is reduced 
to speed things up but it's still pretty long (about 8 minutes or so for 
a WSR-88 reduced scan if I recall).  So faster than 15 minutes is 
probably not going to be of much use.

Now, what you could do is use links to the radar PNGs and write a little 
web page (with your own local server) that simply serves an image into 
the browser of your choice.  I use KMeleon for this even though it's no 
longer supported.  I have several "utilities" running on my own internal 
servers and on any Windows machine I use KMeleon just for viewing those 
(never for external sites).  The neat thing about Kmeleon is that it's 
very lightweight and it can remember window configurations (it calls 
them "Views") so you can pull up a whole bunch of pages at once with one 
click.  I have four monitors running on an internal server on one of my 
side screens using Kmeleon (wall outlet voltage measurement with graph, 
indoor/outdoor temp/humidity with graph, current weather conditions and 
7-day forecast from NWS feed, a webcam that looks out the front window). 
  When I restart the machine, one click brings them all back, window 
sizes included.

In any event, you can get the FFC base reflectivity radar (general 
Atlanta area) at:

http://radar.weather.gov/ridge/lite/N0R/FFC_0.png

And just refresh that every 15 minutes.  Has a timestamp in the file and 
everything.


The PNG is not, however, zoomable, but the volume scan of a radar is of 
little use at the level of city streets which makes zooming a bit silly. 
  Radar is very "blob like", low resolution and only is really useful at 
the size of cities or larger.  Any of those gimmicky things you see on 
the news where they "zoom" the radar in on a city block is just 
extrapolated data.  It would take too long and cost too much money to 
make a radar that could scan with enough detail to show clouds and 
precipitation at street level resolution.

The data source for that PNG was:

http://radar.weather.gov/ridge/radar_lite.php?rid=ffc&product=N0R&loop=no

You can get other images from the same place like the composite scan, 
animated GIFs that would give you relative motion, and some broader 
maps, too.


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