[python #MLB-623842]: MSLP and 1000-500 hPa Thickness with High and Low Symbols

Greetings!

The image you sent back indicated that you are trying to download too much data 
in a single request. This is occurring because you are using `all_times()` on 
our THREDDS server, where there is an entire month's worth of data available. 
Try instead to restrict the times you try to download:

    from siphon.catalog import TDSCatalog
    from datetime import datetime

    gfscat = 
TDSCatalog('http://thredds.ucar.edu/thredds/catalog/grib/NCEP/GFS/Global_0p5deg/catalog.xml')
    dataset = gfscat.datasets['Best GFS Half Degree Forecast Time Series']
    nc = dataset.subset()
    q = nc.query()

    q.time_range(datetime(2021, 6, 20, 12), datetime(2021, 6, 21, 18))
    q.variables('Pressure_reduced_to_MSL_msl', 
'Geopotential_height_isobaric').add_lonlat().accept('netcdf')

    d = nc.get_data(q)

You might also consider reducing the geographic area of data you're downloading 
(or even the level with `q.vertical_level()`):

    q = nc.query()
    q.time_range(datetime(2021, 6, 17, 12), datetime(2021, 6, 21, 18))
    q.lonlat_box(-80, -60, -5, 15)
    q.variables('Pressure_reduced_to_MSL_msl', 
'Geopotential_height_isobaric').add_lonlat().accept('netcdf')

    d = nc.get_data(q)

Hope this helps!

Ryan

> Greetings.
> I am doing one of the Unidata Pyton Gallery tutorials, found at this url (
> http://unidata.github.io/python-gallery/examples/HILO_Symbol_Plot.html),
> but I have a problem why I need model data from TDSCatalog ('
> http://thredds.ucar.edu/thredds/catalog/grib/'
> 'NCEP / GFS / Global_0p5deg / catalog.xml')
> and no re-analysis (
> https://www.ncei.noaa.gov/thredds/ncss/grid/narr-a-files/{0:%Y%m}/{0:%Y%m%d
> }/
> 
> This my code:
> 
> gfscat = TDSCatalog('http://thredds.ucar.edu/thredds/catalog/grib/'
> 'NCEP/GFS/Global_0p5deg/catalog.xml')
> dataset = gfscat.datasets['Best GFS Half Degree Forecast Time Series']
> nc = dataset.subset()
> q = nc.query()
> 
> q.all_times().variables('Pressure_reduced_to_MSL_msl',
> 
> 'Geopotential_height_isobaric').add_lonlat().accept('netcdf')
> 
> d = nc.get_data(q)
> 
> 
> But do error
> 
> [image: image.png]
> 
> 
> Could you help me please?
> Thank you for your answer. Thank you very much for your help.


Ticket Details
===================
Ticket ID: MLB-623842
Department: Support Python
Priority: Low
Status: Closed
===================
NOTE: All email exchanges with Unidata User Support are recorded in the Unidata 
inquiry tracking system and then made publicly available through the web.  If 
you do not want to have your interactions made available in this way, you must 
let us know in each email you send to us.