[gradsusr] 500 hpa & Jetstream

Mon Apr 27 09:41:25 EDT 2015

Stuart,
Use whatever timeseries (or timestep range) fits your needs.  What I sent
you was just an example with six timesteps.  The point was that you need to
change your timestep through a time loop, either by specifying the timestep
(or time/date) as an argument for the variable, or by setting the timestep
(or time/date) for each increment of time.

Stephen Mc

On Mon, Apr 27, 2015 at 9:06 AM, Chorley Weather <
weatherstu at chorleyweather.com> wrote:

> On 27-04-2015 13:33, Stephen McMillan wrote:
> > For the heights to change, you need to change the timestep.  The
> > example you sent has t=5.  If, for example, you want it to vary from
> > timestep 5 to 10, you need t=5 on the first, t=6 on the second, and so
> > forth.  Here's a simple loop, using your sample script:
> >
> > 'set lev 500'
> >
> > t1=5;t2=10
> > ts=t1
> > while(ts<=t2);#start time loop'set gxout shaded'
> > 'set csmooth on'
> > 'set clevs 4920 4960 5000 5040 5080 5120 5160 5200 5240 5280 5320 5360
> > 5400 5440 5480 5520 5560 5600 5640 5680 5720 5760 5800 5840 5880 5920
> > 5960 6000 6040 6080 6120'
> > 'set ccols 61  63  65  67  69  71  73  75  77  79  81  83
> > 85  87  89  18  20  22  24  26  28  30  32  34  36  38
> > 41  43  45  47  49  51'
> >
> > 'd hgtprs(t='ts')'
> >
> > 'define slp  = const((prmslmsl*0.01),0,-u)'
> >
> > 'set gxout contour'
> > 'set ccolor 0'
> > 'set cthick 10'
> > 'set cint 5'
> > 'set clopts 0'
> > 'set clab masked'
> > 'd slp'
> > ts=ts+1
> > endwhile;#end time loop
> > 'cbarn'
> >
> > Stephen Mc
> >
> > On Mon, Apr 27, 2015 at 8:08 AM, Chorley Weather
> > <weatherstu at chorleyweather.com> wrote:
> >
> >> On 26-04-2015 20 [1]:28, Stephen McMillan wrote:
> >>
> >> Stuart,
> >> It would help if you shared the portion of your script that you
> >> used
> >> to attempt doing the 500mb height charts. What is the snag?  What
> >> GrADS error are you getting?  What are you trying to get your code
> >> to
> >> do?
> >>
> >>  Whether you need to define them depends on how you're using
> >> them.
> >> Following is a simple sample, assuming I've opened the gfs 0p25:
> >>
> >> 'set lev 500'
> >> 'set clevs 5160 5280 5400 5520 5640'
> >> 'set ccols 9 4 11 3 7'
> >> 'd hgtprs(t=5)'
> >>
> >> You can also define it first...
> >> 'define hgt500=hgtprs(t=5)'
> >> 'd hgt500'
> >>
> >> Stephen Mc
> >>
> >> On Sun, Apr 26, 2015 at 9:53 AM, Chorley Weather
> >> <weatherstu at chorleyweather.com> wrote:
> >>
> >> Hi guys,
> >>
> >> Still rather new to grads but have managed to create some good
> >> charts running the GFS 0.25, however, I have hit a snag on the
> >> 500mb
> >> height chart. Ive scripted all the colour and shading, including
> >> the
> >> contour bar but the hgt500 code will not work. Does this need
> >> defining and if so can someone please share the definition. Also
> >> I'd
> >> love a jet stream chart, however, I am also struggling with that.
> >> Any info would be much appreciated.  I've attached my precip &
> >> rainfall chart to show I'm not completely without hope :)
> >>
> >> Thanks in advance,
> >> Stuart.
> >>
> >> --
> >> Chief Forecaster & Owner
> >> _______________________________________________
> >> gradsusr mailing list
> >> gradsusr at gradsusr.org
> >> http://gradsusr.org/mailman/listinfo/gradsusr [2] [1]
> >>
> >> Links:
> >> ------
> >> [1] http://gradsusr.org/mailman/listinfo/gradsusr [2]
> >>
> >> _______________________________________________
> >> gradsusr mailing list
> >> gradsusr at gradsusr.org
> >> http://gradsusr.org/mailman/listinfo/gradsusr [2]
> >  Hi Stephen,
> >
> >  Thank you very much for your help. The sample worked fine and I have
> > manged to create a chart including a pressure overlay. However, the
> > issue I now have is the heights don't change when I run the gfs data.
> > I still get the same heights but the pressure works fine. I've
> > attached some of my script for you to view. Not sure what I'm missing
> > to make the heights run with the gfs data. All my other charts work
> > fine so I know the noaa/dods link is fine.
> >
> >  'set lev 500'
> >  'set gxout shaded'
> >  'set csmooth on'
> >  'set clevs 4920 4960 5000 5040 5080 5120 5160 5200 5240 5280 5320
> > 5360 5400 5440 5480 5520 5560 5600 5640 5680 5720 5760 5800 5840 5880
> > 5920 5960 6000 6040 6080 6120'
> >  'set ccols 61  63  65  67  69  71  73  75  77  79  81
> > 83  85  87  89  18  20  22  24  26  28  30  32  34  36
> > 38  41  43  45  47  49  51'
> >
> >  'd hgtprs(t=5)'
> >
> >  'define slp  = const((prmslmsl*0.01),0,-u)'
> >
> >  'set gxout contour'
> >  'set ccolor 0'
> >  'set cthick 10'
> >  'set cint 5'
> >  'set clopts 0'
> >  'set clab masked'
> >  'd slp'
> >
> >  'cbarn'
> >
> >  Regards,
> >  Stuart
> >
> >  --
> >  Chief Forecaster & Owner
> > _______________________________________________
> >  gradsusr mailing list
> >  gradsusr at gradsusr.org
> >  http://gradsusr.org/mailman/listinfo/gradsusr [2]
> >
> >
> >
> > Links:
> > ------
> > [1] tel:26-04-2015%2020
> > [2] http://gradsusr.org/mailman/listinfo/gradsusr
> >
> > _______________________________________________
> > gradsusr mailing list
> > gradsusr at gradsusr.org
> > http://gradsusr.org/mailman/listinfo/gradsusr
> Hi Stephen,
>
> Again many thanks for your assistance. The time series I have been using
> for all my charts is below. Would I need to change this?
>
> function main(args)
>
> * Parse the arguments: date, hour
>    if (args = '')
>    prompt 'Enter forecast date (example, 20110717) --> '
>    pull date
>    prompt 'Enter forecast hour (example, 00 or 06 or 12 or 18) --> '
>    pull hour
>    else
>    date = subwrd(args,1)
>    hour  = subwrd(args,2)
>    endif
>
> 'reinit'
> 'sdfopen
> http://nomads.ncep.noaa.gov:9090/dods/gfs_0p25/gfs'date'/gfs_0p25_'hour'z'
>
> * Get info from the descriptor file
> 'q ctlinfo'
> _ctl = result
> _undef = getctl(undef)
> _tdef = getctl(tdef)
> _zdef = getctl(zdef)
>
> maps = 81
>
> * Get the Time axis info
> tsize = subwrd(_tdef,2)
> _t1 = 1       ;* 2nd half of timeseries
> _t2 = 45
> tsize = _t2 - _t1 + 1
> 'set t '_t1' '_t2
> 'q dims'
> times  = sublin(result,5)
> _time1 = subwrd(times,6)
> _time2 = subwrd(times,8)
> _tdim = _time1' '_time2
>
> tincr = subwrd(_tdef,5)
> _tdef = 'tdef 'tsize' linear '_time1' 'tincr
>
> huh = subwrd(_tdef,4)
>
> Regards,
> Stuart.
>
>
> --
> Chief Forecaster & Owner
> _______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr
>
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