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LJH · 31-07-2017, 03:55

Quote:

Additionally, it would be nice to get the UK Met weatherfaxes working, but they have a rotating set of numeric identifiers that needs to be figured out.
We would like to know what the sequence is so a download approach can be worked out. The site is here (both B&W and Color)

Surface pressure charts - Met Office

There appear to be two different number sets on the met office web site. The first in the url "fcTime=1501174800" The number used here is the number of seconds from 1 Jan 1970 0:00:00.

The images appear to be randomly numbered. I could not see an precise relationship between the numbering based on either chart type, or chart valid time. Also the difference between the numbering of the BW and Color charts varies somewhat randomly. I have a feeling that it may incorporate a time stamp from when it was saved.

Since the chart ids are dynamic, the best approach may be to use the URL, which is predictable and then scrape the <img> tags (src= and alt=) for the charts from the source HTML.

rgleason · 31-07-2017, 10:06

When I do Surface pressure charts - Met Office
the Analysis comes up.

"Since the chart ids are dynamic, the best approach may be to use the URL, which is predictable and then scrape the <img> tags (src= and alt=) for the charts from the source HTML."

Can you illustrate to me how we would do this? - I am not familiar with the technique. Several links as an example would help I think.

rgleason · 31-07-2017, 10:16

Quote:

Originally Posted by stelian

Here is an updated version.

Changelog:
- fix UK MET - Central longitude swap
- fix UK MET - Central - A projection
- fix weathercharts.org Surface Analysis URL

Stelian.

Thanks,

I've been working on the files since before this post, but can copy the full

UK MET
weathercharts.org

for both weatherfaxinternetretrieval.xml and coordinatesets.xml from yours.

Are you aware that If you have to make a new coordinate set you will find it in the usercoordinateset.xml file?

Would you mind perfecting those two urls and links, so when I copy them over they are done? That would be very helpful.

I will stay away from making any changes to those sections, since you are working on them! I will await your response.
Thanks Rick

rgleason · 31-07-2017, 10:21

Quote:

Originally Posted by stelian

In fact, looking at the "longitude swap bug", it looks like many areas are wrong.

For example, the first area in WeatherFaxInternetRetrieval.xml (NOAA - Boston - 1), will be filtered out if the boat is placed in Boston.

The reason is the same:
<Area Name="1" lat1="28N" lat2="52N" lon1="45W" lon2="85W" />

Should be:
<Area Name="1" lat1="28N" lat2="52N" lon1="85W" lon2="45W" />

And there are many many others...

Stelian, You are our expert here. Can you give us a rule about how they must all be formatted?

For latitude is it always western most first up to and not including Greenwich?

Once I know the rule I will pour through all of NOAA, NOAA-OPC & OPC and correct it.

Thanks, never realized or utilized that search function.

rgleason · 31-07-2017, 10:24

Quote:

Originally Posted by LeaseOnLife

I checked some old favorites:
OK for me are: Fiji, South Africa, Chile, Bermuda

For Mauritius the sat pic is ok, but the synoptic chart calibration is off

Dirk

Dirk,
Thank you. So I can assume that

FIJI
South Africa
Chile
Bermuda

are all OK. That is very helpful!

I will try to change the one Mauritius Chart now, so it will be OK.

Keep them coming! Thanks.

stelian · 31-07-2017, 11:08

Quote:

Originally Posted by rgleason

Stelian, You are our expert here. Can you give us a rule about how they must all be formatted?

For latitude is it always western most first up to and not including Greenwich?

Once I know the rule I will pour through all of NOAA, NOAA-OPC & OPC and correct it.

Thanks, never realized or utilized that search function.

I'm no expert, but from what I read in the source, the zone starts at lon1, then go East until reaching lon2 (if you consider that western longitudes are negative and eastern are positive, it is like going in the natural (nagative to positive) direction).

And UK Met and weathercharts.org are fully validated, you can use the latest version I've sent.

Stelian.

LeaseOnLife · 31-07-2017, 11:50

Quote:

Originally Posted by rgleason

Dirk,
Thank you. So I can assume that

FIJI
South Africa
Chile
Bermuda

are all OK. That is very helpful!

I will try to change the one Mauritius Chart now, so it will be OK.

Keep them coming! Thanks.

I only check for valid download links and then the overlay on the chart. I haven't checked on the reversed longitude issue.

India: all links seem to be invalid (download fails) and a quick search has not brought up anything meaningful, please remove/comment out until we find valid links.

LeaseOnLife · 31-07-2017, 12:19

French Polynesia: all display OK
Singapore: all links are dead

rgleason · 31-07-2017, 14:50

I'm probably the one who screwed up the searches by reversing, and that is probably mainly for the NOAA, Noaa-OPC and OPC websites. Sooo I'll fix em.

rgleason · 31-07-2017, 16:35

India Met Marine Section appears to be here
IMD - Marine Meteorology

India appears to be using lots of PDF popup up automatically. I am not able to find the chart and weatherfax resources that we used to have, which is a real shame.

Here is an interesting image on Vorticity from their satellite data.
http://satellite.imd.gov.in/img/3D_vor850.jpg

Here is another satellite image which could be useful
Satellite Images

If someone could investigate this India Met website and any others to provide some useful surface charts and forecasting, that would be great.

rgleason · 31-07-2017, 16:49

In searching for India's respected MET these links were found.
A lot of these have dropdown selections.
We need to find out if there is other info available and determine what is useful.

Indian Meteorological Department - Home
Numerical Weather Prediction
Numerical Weather Prediction
Numerical Weather Prediction
Numerical Weather Prediction
Numerical Weather Prediction
Satellite Images

rgleason · 31-07-2017, 16:53

Here is something India
Mean Sea Level Pressure at 24hr periods.
Numerical Weather Prediction

wind & rain
http://nwp.imd.gov.in/cfs.php?param=windrf

rainfall
http://nwp.imd.gov.in/wrf27pro.php

http://nwp.imd.gov.in/wrf/WRFd01-MSLP_00.png

IMD:GFS Model
http://nwp.imd.gov.in/gfsproducts.php

Hit view extended range
http://nwp.imd.gov.in/cfs_form_all.php

I need someone to make a good list of urls for
MSLP Mean Sea Level Pressure
Wind & Rain
IMD:GFS Model MSLP
IMD:GFS Model Wind and Rain

for a good range on 24hr interval.
Try to get sequences of images with the exact same coordinate and projection characteristics.

We can turn that into our India weather data.

rgleason · 31-07-2017, 17:09

About satellite images
https://groups.google.com/forum/#!to...-s/YjulIkdinYE

Infrared
http://satellite.imd.gov.in/img/3Dglobe_ir1.jpg

http://satellite.imd.gov.in/img/3Dasiasec_wv.jpg

rgleason · 31-07-2017, 18:00

stelian · 01-08-2017, 02:19

I've found another error in the weathercharts.org URLs: one of the prognosis charts was missing.

Find attached a new version (edited, including only weathercharts.org data)

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