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Jack Glendening[_2_]
May 18th 08, 05:22 PM
For those who missed the announcement I made last year, high
resolution -- 1.3 to 12 km -- soaring weather forecasts can be
produced for your region if you have a motivated/capable volunteer to
run the (free) RASP program I have created. This is much finer
resolution than is available from the US RUC/NAM/GFS models and hence
includes the weather influence of smaller scale terrain. This high
resolution is _not_ obtained by interpolation of RUC/NAM/GFS forecasts
but by solving the fundamental "equations of motion" (the same ones
used by RUC/NAM/GFS) and hence provides state-of-the-art forecasts.
How can this be done when RUC/NAM/GFS forecasts require a
supercomputer? The forecasts cover a much smaller region and do not
extend so far in time and so are do-able on a fast CPU PC, though the
region covered and resolution obtainable does depend upon the
available computer power.

Currently RASP is being run for over 20 regions around the world.
While its primary emphasis is upon thermal BLIPMAP forecasts, the
model also predicts mt. wave (unlike RUC/NAM BLIPMAPs) and has been
successfully used by Hawaiian pilots to predict wave over Mauna Loa
when no cloud markers were present. Note that the volunteer must have
access to a fast-CPU Linux PC and have some computer savvy - I provide
written instructions but do not do any handholding for those wanting
to install RASP, though help can be obtained though the RASP forum
from other users. For more information and a list of current RASP
regions see http://www.drjack.info/RASP/

Jack Glendening

Darryl Ramm
May 18th 08, 06:35 PM
And not just wave. The RASP forecacasts for Panoche and Williams show
uncanny ability to predict the location of convergence. Including
movement of convergence lines during the day. I and other pilots have
successfully used this to find blue convergence in both locations. On
days where things are really predicted to move around I'll even print
out the BL Max up/down (convergence) charts and take them with me.

Thanks for RASP!

Darryl

On May 18, 9:22 am, Jack Glendening > wrote:
> For those who missed the announcement I made last year, high
> resolution -- 1.3 to 12 km -- soaring weather forecasts can be
> produced for your region if you have a motivated/capable volunteer to
> run the (free) RASP program I have created. This is much finer
> resolution than is available from the US RUC/NAM/GFS models and hence
> includes the weather influence of smaller scale terrain. This high
> resolution is _not_ obtained by interpolation of RUC/NAM/GFS forecasts
> but by solving the fundamental "equations of motion" (the same ones
> used by RUC/NAM/GFS) and hence provides state-of-the-art forecasts.
> How can this be done when RUC/NAM/GFS forecasts require a
> supercomputer? The forecasts cover a much smaller region and do not
> extend so far in time and so are do-able on a fast CPU PC, though the
> region covered and resolution obtainable does depend upon the
> available computer power.
>
> Currently RASP is being run for over 20 regions around the world.
> While its primary emphasis is upon thermal BLIPMAP forecasts, the
> model also predicts mt. wave (unlike RUC/NAM BLIPMAPs) and has been
> successfully used by Hawaiian pilots to predict wave over Mauna Loa
> when no cloud markers were present. Note that the volunteer must have
> access to a fast-CPU Linux PC and have some computer savvy - I provide
> written instructions but do not do any handholding for those wanting
> to install RASP, though help can be obtained though the RASP forum
> from other users. For more information and a list of current RASP
> regions seehttp://www.drjack.info/RASP/
>
> Jack Glendening

Jack Glendening[_2_]
May 18th 08, 09:05 PM
I hesitate to mention this because I have some concerns about the
idea of displaying a _forecast_ in a PDA during flight, but since I
know
you're into PDA flight software I will mention that the XCSoar PDA
program is capable of displaying BLIPMAP data (loaded on the ground
from the net) as a background map. So you could just load it up and
fly to your convergence line! (but I don't really think things are
quite that easy)

Jack Glendening

Darryl Ramm
May 18th 08, 10:00 PM
On May 18, 1:05 pm, Jack Glendening > wrote:
> I hesitate to mention this because I have some concerns about the
> idea of displaying a _forecast_ in a PDA during flight, but since I
> know
> you're into PDA flight software I will mention that the XCSoar PDA
> program is capable of displaying BLIPMAP data (loaded on the ground
> from the net) as a background map. So you could just load it up and
> fly to your convergence line! (but I don't really think things are
> quite that easy)
>
> Jack Glendening

I'm often mistaken for a computer geek :-) And I use SeeYou Mobile.
You would also need the ability to scroll images for different times.
I'm old enough my color contrast is shot, I can barely see the PDA
display in flight and that requires a full white background so even if
this was available I'd probably not be able to/want to use it. A sheet
of paper has an amazingly easy to use user interface and is visible in
full sunlight.

Before the commercials start, yes I know about ClearNav.

Thanks

Darryl

May 20th 08, 05:23 AM
On May 18, 2:00*pm, Darryl Ramm > wrote:
> On May 18, 1:05 pm, Jack Glendening > wrote:
>
> > I hesitate to mention this because I have some concerns about the
> > idea of displaying a _forecast_ in a PDA during flight, but since I
> > know
> > you're into PDA flight software I will mention that the XCSoar PDA
> > program is capable of displaying BLIPMAP data (loaded on the ground
> > from the net) as a background map. *So you could just load it up and
> > fly to your convergence line! *(but I don't really think things are
> > quite that easy)
>
> > * * * * Jack Glendening
>
> I'm often mistaken for a computer geek :-) And I use SeeYou Mobile.
> You would also need the ability to scroll images for different times.
> I'm old enough my color contrast is shot, I can barely see the PDA
> display in flight and that requires a full white background so even if
> this was available I'd probably not be able to/want to use it. A sheet
> of paper has an amazingly easy to use user interface and is visible in
> full sunlight.
>
> Before the commercials start, yes I know about ClearNav.
>
> Thanks
>
> Darryl

A paper print? What a concept! ;-D Cool!

Jack Glendening[_2_]
May 29th 08, 05:13 AM
BTW Darryl, another example of how running a model which utilizes the
"equations of motion" at a high resolution (i.e. higher than used by
government models) can produce more accurate thermal forecasts occurs
for the Central Valley (of California). Forecasts based on RUC/NAM
very often over-predict the thermal tops there, as many have noticed
probably including yourself. But RASP-predicted thermal tops are
typically much lower over both the northern Central Valley (Williams
RASP) and southern Central Valley (Panoche RASP). The reason is that
the 4km resolution "equations of motion" is better able to simulate
the mountain-valley circulation pattern, i.e. the upward motion over
the surrounding mountains and downward vertical motion over the
valley, than is the 12km resolution RUC/NAM, and that downward motion
over the valley "caps" thermals at a lower height than would otherwise
occur.

Jack

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