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[python #IIA-419796]: 0° longitude problem - MetPy Monday #107



Hi,

Hi,

Looking at your query:

    query.lonlat_box(north=70, south=25, east=320, west=60)

and the image plot against the maps, it looks like everything else is correct, 
but the image plot is incorrect. I think this is due to the query, specifically 
`east=320, west=60`, which requests data starting at 60 degrees EAST longitude, 
continuing eastward across the globe and across the international dateline 
until reaching 320 EAST longitude (40 W longitude). If you look carefully at 
your image plot, I think I can make out the US in the image on the left side, 
though flipped left-to-right. I'm not sure what values you used to do the 
plotting, but I'm almost positive they're not quite correct for the data you 
actually got back from the server.

Currently, because the GFS model output is on longitudes from 0->360, there's 
no way to request data across the 0 degree meridian. This will be available in 
the next version of the THREDDS data server, which will have a stable release 
next year.

Ryan

> Hi -
> 
> I am aware (and sufferer) of the long-standing 0° longitude problem when
> displaying meteorological fields in various software packages. Seeing
> your MetPy Monday #107 (I love these examples) I thought to give it
> another try. To my positive surprise moving the temperature image across
> the 0° longitude worked just fine, no gap or whatsoever or other
> artificial gimmick in the image. Then I wanted to overlay contours (MSLP
> in this case),but those are only show up  outside the temperature box,
> i.e. they wrap around the globe outside the chosen box. The attached
> file shows the the lonlat query for both temperature and MSLP as wella s
> the resulting plot. Any comment on this issue?


Ticket Details
===================
Ticket ID: IIA-419796
Department: Support Python
Priority: Low
Status: Closed
===================
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