NOAA APT weather satellite images

 

Recorded at Northampton UK by G6KIZ using a R2ZX receiver

Currently there are 3 fully operational NOAA APT weather satellites in operation NOAA 15 NOAA 18 and the latest NOAA 19 which was launched on the 6th February 2009.

NOAA 17 developed a serious fault in February 2010. The fault resulted in badly degraded images which then impacted composites built using them. For this reason I took the decision to cease recording of NOAA 17 images entirely however release 2.10.7 of WXtoImg provided the option of excluding specific satellites from composite images so this option was used instead. From May 8 2010 most NOAA 17 passes produced good images with only the occasional poor one but I don’t recall seeing a good one lately so I am using the WXtoImg 2.10.11 option to exclude in from the web pages. The NOAA POES status page should carry the latest information.

All the satellites are in approximately circular polar orbits at around 850km altitude and transmit 10w RF in the 137-138MHz band which makes them relatively easy to receive with a simple antenna. The main problem with reception in the UK is the staggeringly stupid decision to allow text pagers to operate in the same band. The authorities would doubtless argue that any problems are the fault of the APT receiver but low cost equipment cannot realistically be expected to cope with the intermodulation interference caused but a powerful nearby transmitter operating a few KHz away from the satellite frequency. The result is that pager interference will be seen on most of the pictures here as short dark lines where a pager signal wiped out the satellite. The demodulated signal is processed through a normal PC soundcard and the two greyscale images at different infrared wavelengths combined to produced the false colour images displayed below.

The MCIR-precip composite images give a good idea of where there is likely to be rain by use of bright false colouring. Looking at two images recorded a few hours apart can usually show the probable path the rain will follow. Note though that the colours are only an indication of possible rain not that rain is actually reaching the ground.



Paul Glover’s images
These images donated by Paul Glover of Worthing illustrate just what can be achieved with fairly modest amateur equipment when there is no local pager tower intermodulation interference.

Feel free to download any images for your own purposes – they can make attractive desktop wallpapers for instance.

Hardware problems

I have been experiencing intermittent hardware problems and there will be periods when no updates get uploaded

I am not always able to reset the equipment so the problem can persist for some time. I replaced the network switch which I suspect was the cause of the latest round of problems on 2nd September 2016. Only time will tell if this has fixed anything.

Well that didn’t go too well – a week later and once again my home network has failed. It must be the recent router change I made to a Netgear D7000. I hadn’t made this connection immediately because when M0XDK checked on the problem the first time the switch had powered itself down probably due to overheating. It hadn’t done this when my daughter reset it the next time nor when I finally got home and reset everything myself but I was still blaming it. I will be returning the router next time I’m home later this month.

The Netgear D7000 router has now been replaced with an Asus DSL-AC68U which I am hoping will remain online. As there is only just over 3 weeks of the caravan season left I’ll at least be able to sort out any issues quicker until the spring. Given the abysmal return on advertising clicks I may well just shut the site down anyway though as the costs are nowhere near being covered.

I have been contacted by a couple of people who thought my comments above meant I would be shutting DigitalHam down – of course I may some time in the future but certainly not immediately – I was just in a bad mood about my router problems which I’ve detailed here for those interested.

Image upload problems

Regular user of this page will be aware that there have been frequent occasions where updated pictures are not being uploaded. Sometimes these are hardware issues but of late there have been issues uploading to my hosters Krystal from WxToIMG. I am making yet another attempt to sort this out by hosting the images from home using a Raspberry Pi 2 webserver. It is quite likely that once my prepaid hosting time is up I will be hosting Digitalham entirely from home.

Hosting

I am now hosting Digitalham entirely from home on an old Intel core I3 machine I bought on eBay. This means if the server goes down while I am away from home it could be down for a while however Linux is pretty robust – my Raspberry Pis have never failed so far. The server response time is considerably faster than the shared hosting but of course the sever bandwidth is limited to the 20Mbps upstream my home internet connect supports.

I had problems with getting the weather page which carried the webcam and WeeWX weather report to work so I have removed it from Digitalham. The WeeWX page itself does work OK but not the method I was using to include it in Digitalham. I have not had time to investigate that but if interested the page is available at https://home.digitalham.co.uk/weewx/index.html

WXtoImg is still running on Windows and transferring the satellite picture data to the Digitalham server by FTP but I intend to investigate running that on the server too which means I will be able to have just the one machine running 24×7 again rather than the current two.

Weather satellite images recorded at Northampton, United Kingdom

Latitude: 52.226, Longitude: -0.905 Software: WXtoImg version 2.11.2 beta Receiver: R2ZX Antenna: Bill Sykes and Bob Cobey QFH


Next Scheduled Satellite Pass - NOAA 18

Start of Pass : 22 Oct 2017 18:19 GMT Daylight Time
Time Available : 22 Oct 2017 18:44 GMT Daylight Time

May not be recorded if less than 15 minutes after the current pass : 22 Oct 2017 16:57 GMT Daylight Time

Click on any thumbnail image below to see it at full size



Composite MCIR
Composite MCIR
22 Oct 2017 15:57

Composite MSA
Composite MSA
22 Oct 2017 15:57

Composite MCIR-precip
Composite MCIR-precip
22 Oct 2017 15:57

NOAA 19 MCIR
NOAA 19 MCIR
22 Oct 2017 15:57

NOAA 19 MSA
NOAA 19 MSA
22 Oct 2017 15:57

NOAA 19 MCIR-precip
NOAA 19 MCIR-precip
22 Oct 2017 15:57

Next Scheduled Satellite Passes over Northampton, United Kingdom

Satellite
Name
Start of Pass Time Available Direction Maximum Elevation
Degrees (East or West)
Frequency
MHz
UTC Local Time* UTC Local Time*
NOAA 18 22 Oct 17:19 22 Oct 18:19 22 Oct 17:44 22 Oct 18:44 137.9125
NOAA 15 22 Oct 17:31 22 Oct 18:31 22 Oct 17:46 22 Oct 18:46 137.62
NOAA 18 22 Oct 18:59 22 Oct 19:59 22 Oct 19:12 22 Oct 20:12 137.9125
NOAA 19 23 Oct 04:12 23 Oct 05:12 23 Oct 04:25 23 Oct 05:25 137.10
NOAA 18 23 Oct 07:15 23 Oct 08:15 23 Oct 07:33 23 Oct 08:33 137.9125
NOAA 15 23 Oct 07:20 23 Oct 08:20 23 Oct 07:35 23 Oct 08:35 137.62
NOAA 18 23 Oct 08:56 23 Oct 09:56 23 Oct 09:08 23 Oct 10:08 137.9125
NOAA 19 23 Oct 14:04 23 Oct 15:04 23 Oct 14:17 23 Oct 15:17 137.10

* local time is GMT Daylight Time

Since converting DigitalHam to use WordPress I have added some old email conversations as comments.



  31 Responses to “NOAA APT weather satellite images”

  1. Hi,
    Thanks for the heads up. It appears to have sorted itself now and I can’t find any error with my monitoring script which didn’t pick it up.

    It may be that there were two passes close together. If that happens and it hasn’t completed the earlier pass it won’t switch to the later one.

    Markl