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<p><font face="DejaVu Sans">I have not done a detailed debug, but it
looked like the legacy model crashed, I assume because of the
timestep issue, but it may have been another upstream issue.</font></p>
<p><font face="DejaVu Sans">Both models are running again this
morning. I don't plan on changing any criteria for this reason. </font></p>
<p><font face="DejaVu Sans">But I do intend playing with the "beta"
model to see if we can get a run with resolution to match or
better the 1.3km we have on the legacy one. This could come in
useful for the wave season. That version could possibly be even
less stable, but it is worth the trade off for wave and foot
launch pilots. :-)</font></p>
<p><font face="DejaVu Sans">Thanks</font></p>
<p><font face="DejaVu Sans">Ian</font></p>
<p><font face="DejaVu Sans"><br>
</font></p>
<div class="moz-cite-prefix">On 4/9/26 11:50,
<a class="moz-txt-link-abbreviated" href="mailto:rasp.admin@stratus.org.uk">rasp.admin@stratus.org.uk</a> wrote:<br>
</div>
<blockquote type="cite"
cite="mid:D37243B9-B41F-4AF9-BFF9-7908DA44FA64@stratus.org.uk">
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<div dir="ltr">Ah ok, so the GFS issue just happened to be at the
same time.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">On the model crashing with time-step too long, the
one I set up originally for you is a compromise. It is possible
to always make the higher resolution runs complete (smaller time
step) but will take longer to finish (or be too late to be of
use).</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">What I always suggest is again as said, which is to
use the lower resolution model instead over. This will be almost
the same for most parameters. </div>
<div dir="ltr"><br>
</div>
<div dir="ltr">However if looking for wave, then the lower
resolution will probably not provide the detail to see on the
plots. But for wind speed/direction, thermal height, cloud base,
temperature, it will be about right. Where it probably won’t be
right is across sharp ridges or topographically complex areas as
the topographic model used, smooths these out.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Ian: If you want something that checks the basic
parameters against airport/airfield METAR reports for a
‘quality’ check, let me know.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Regards,</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">Darren</div>
<div dir="ltr"><br>
<blockquote type="cite">On 9 Apr 2026, at 10:16, Ian
<a class="moz-txt-link-rfc2396E" href="mailto:ian@zomerlust.org"><ian@zomerlust.org></a> wrote:<br>
<br>
</blockquote>
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<div dir="ltr">
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<p><font face="DejaVu Sans">There was one run which failed to
converge. Ie the model got into a loop where instead of
each step getting closer to a solution the results started
to diverge again. This leads to a model crash.</font></p>
<p><font face="DejaVu Sans">It is caused by an anomaly in the
input data - often associated with unusual weather events
like "cut off lows" (but that was not the cause of recent
crashes). This coupled with compromises made when the
model was constructed makes the model run crash. It
happens on a handful of runs a year.</font></p>
<p><font face="DejaVu Sans">In order to avoid this, the model
would have to have smaller "time step" intervals and/or a
smaller "resolution ratio" ie 12km -> 4km -> 1.3km.
That would make it run slower and use more computer time
and electric power. The parameters selected were a
compromise that work most of the time.</font></p>
<p><font face="DejaVu Sans">When this happens I have seen the
same date forecast crash on subsequent forecasts runs, ie
1 day ahead, night before etc.</font></p>
<p><font face="DejaVu Sans">If you see this, have a look at
the alternate model legacy vs beta. It is possible one
crashes when the other manages to resolve.</font></p>
<p><font face="DejaVu Sans">Regards</font></p>
<p><font face="DejaVu Sans">Ian</font></p>
<p><font face="DejaVu Sans"><br>
</font></p>
<div class="moz-cite-prefix">On 4/8/26 20:40, AirSchool
Paragliding wrote:<br>
</div>
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cite="mid:CAPKYDukPiNb+hWhGodoEFu4nkaN2WJOONwPdxcxFk8gQbDhbkQ@mail.gmail.com">
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<div dir="ltr">Greetings all<br>
<br>
Just noticed that a few <span class="Asgive ng"
style="border-style:none;background:none">of the </span>RASP
days haven't been updated since yesterday e.g. RASP 1.3km
d0 and d2, RASP 2km d4 and d5<br>
<br>
Many thanks<br>
Ria</div>
</blockquote>
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